ArticlePDF Available

Misconceptions of cell division held by student teachers in biology: A drawing analysis

Authors:

Abstract and Figures

The purpose of this study was to identify biology student teachers' misconceptions of cell divisions using drawings and interviews. Data were collected from 124 biology student teachers. An analysis of drawings and interviews suggested that biology student teachers have a series of significant problems and misconceptions regarding cell division and structuring of concepts in a meaningful manner. These problems were mainly associated with meiosis rather than mitosis. The students confused the stages of the cell division process and the events occurring at these stages. Some misconceptions identified from this study included that DNA replication occurs in the prophase during the cell division, interphase is the resting phase of mitosis, the chromosome number is doubled in prophase of mitosis and halved in anaphase of mitosis, the chromosome number remains the same during meiosis-I and it is halved during meiosis-II, and a chromosome has always two chromatids during cell division. These results were compared with related literature and recommendations were made for teachers and researchers for future studies to overcome students' misconceptions.
Content may be subject to copyright.
Scientific Research and Essay Vol. 5 (2), pp. 235-247, 18 January, 2010
Available online at http://www.academicjournals.org/SRE
ISSN 1992-2248 © 2010 Academic Journals
Full Length Research Paper
Misconceptions of cell division held by student
teachers in biology: A drawing analysis
Musa Dikmenli
Selcuk University, Ahmet Kelesoglu Education Faculty, Department of Secondary Science and Mathematics Education,
Program of Biology Education, 42090 Konya/Turkey. E-mail: mdikmenli@selcuk.edu.tr. Tel: (90) 332-3238220. Fax: (90)
332-3238225.
Accepted 17 December, 2009
The purpose of this study was to identify biology student teachers’ misconceptions of cell divisions
using drawings and interviews. Data were collected from 124 biology student teachers. An analysis of
drawings and interviews suggested that biology student teachers have a series of significant problems
and misconceptions regarding cell division and structuring of concepts in a meaningful manner. These
problems were mainly associated with meiosis rather than mitosis. The students confused the stages of
the cell division process and the events occurring at these stages. Some misconceptions identified
from this study included that DNA replication occurs in the prophase during the cell division,
interphase is the resting phase of mitosis, the chromosome number is doubled in prophase of mitosis
and halved in anaphase of mitosis, the chromosome number remains the same during meiosis-I and it
is halved during meiosis-II, and a chromosome has always two chromatids during cell division. These
results were compared with related literature and recommendations were made for teachers and
researchers for future studies to overcome students’ misconceptions.
Key words: Biology education, cell division, students’ drawings, misconceptions.
INTRODUCTION
A major thrust in science education research over the
past three decades has been the documentation of
students’ misconceptions in a wide range of subject
areas (Pfundt and Duit, 2004). The term “misconceptions”
has been coined to describe alternative conceptions,
naive theories or views of science which are not consis-
tent with concepts currently accepted by the community
of scientists. Students’ misconceptions are often deeply
rooted, instruction-resistant obstacles to the acquisition of
scientific concepts and remain even after instruction.
Misconceptions are part of a larger knowledge system
that involves many interrelated concepts that students
use to make sense of their experiences. Students hold
misconceptions that were developed before and during
their early school years. These misconceptions may be
compounded by the teacher or the textbook (Bahar,
2003; Wandersee et al., 1994).
A large number of prior studies reported that primary
and secondary school students have many conceptional
problems concerning cell biology and genetics (Flores et
al., 2003; Lewis and Wood-Robinson, 2000; Marbach-Ad
and Stavy, 2000). However, any detailed research related
to biology student teachers’ misconceptions about cell
division was not found. If higher education curriculum
designers knew students’ misconceptions, it might be
helpful to prepare effective teaching strategies. Teachers
can play an important role in teaching scientific concepts
and, from a constructivist perspective, students should
gain meaningful knowledge about biological concepts like
cell division. Biologically literate students should be able
to use and apply basic biological concepts when
considering biological problems or issues. Prior studies
have shown that students experience difficulties in
learning concepts related to the cell division process
(Kindfield, 1994). Cell division constitutes the basis for
genetics, reproduction, growth, development, and
molecular biology subjects in the biology curriculum. As a
matter of fact, a majority of the students or teachers
evaluated topics such as gene, DNA, chromosome, and
cell division as difficult to learn topics (Oztas et al., 2003).
Research on students’ conceptual understandings
often indicates that, even after being taught, students use
236 Sci. Res. Essays
misconceptions different from the scientific concepts
(Lewis et al., 2000; Yesilyurt and Kara, 2007). Reasons
for these misconceptions include students’ inability to
differentiate between doubling (replication), pairing
(synapsis), and separating (disjunction), as well as
determining whether or not these processes occur in
mitosis, meiosis, or both (Smith, 1991). Further miscon-
ceptions include a lack of understanding of basic terms
confusing chromatids with chromosomes, or repli-cated
chromosomes with unreplicated chromosomes, etc.
(Kindfield, 1994). This is a concern for instructors
because cell division processes are fundamental to the
understanding of growth, development, reproduction, and
genetics (Chinnici et al., 2004; Cordero and Szweczak,
1994).
Studies conducted on problem-solving related to
genetics revealed that students have some miscon-
ceptions regarding the stages of meiosis (Brown, 1990;
Stewart and Dale, 1989). Accurate organizing of many
concepts in cell biology is dependent on the degree of
understanding cell division (Smith and Kindfield, 1999).
As a matter of fact, a study related to genetics mentioned
that students possess misconceptions and inadequate
knowledge about the behavior of chromosomes and
transference of genetic material during cell division. It
further suggested that such misconceptions lead to
conceptual problems in genetics (Kibuka-Sebitosi, 2007).
Yilmaz et al. (1998) studied the misconceptions
possessed by 9th grade students relating to cell division,
and the effect of the conceptual teaching regarding
elimination of such conceptions. They posit that concept-
tual teaching is an effective method for understanding the
concepts related to cell division and for elimination of
misconceptions. Lewis et al. (2000) studied the students’
levels of understanding in regards to mitosis, meiosis,
and fertilization. Conclusions of this study have shown
that students possess inadequate knowledge and nume-
rous misconceptions related to the physical relationships
between the genetic material and the chromosomes, and
the relationships between the behavior of the chromo-
somes and continuity of the genetic information. Lewis et
al. (2000) further emphasized the fact that the students
mainly experience difficulties for explaining the relation-
ships between the cell, nucleus, chromosome, and gene
concepts, and the similarities and differences between
mitosis and meiosis. Clark and Mathis (2000) indicated
that students experience difficulties particularly for
discriminating chromatids, chromosomes, and the homo-
logous parts of the chromosomes during the cell division
process. Conclusions of this study have shown that these
difficulties related to the structure and behavior of the
chromosome can be easily identified and removed by
means of models. Atilboz (2004) studied the level of
understanding and misconceptions of 9th grade students
related to mitosis and meiosis. Conclusions of this study
have shown that students experience difficulties in
understanding fundamental concepts, such as DNA,
chromosome, chromatid, homologous chromosomes,
haploid and diploid cells, and the relationships between
such concepts, and possess some misconceptions. Saka
et al. (2006) have shown that science student teachers
have misconceptions, particularly regarding the concepts
of gene and chromosome, in accordance with their
findings obtained from written responses and drawings.
Kruger et al. (2006) studied the concepts of students
regarding cell division and growth. Conclusions of this
study revealed that students generally focus on the
increase occurring with number of the cells, as a result of
cell division and disregard the growth occurring in the
cells. Kruger and colleagues also indicated that such
difficulties experienced during understanding such
concepts might be overcome by learning activities that
researchers have developed. Riemeier and
Gropengießer (2008) analyzed the difficulties in learning
as experienced by the 9th grade students regarding cell
division, and their conceptual understandings within
teaching experiments. They have shown that well
planned teaching activities for the cell biology might
enhance the conceptual development process and might
contribute to the conceptual learning by the students. It is
obvious from the literature that misconceptions related to
cell division processes lead to a series of problems for
the biology teaching. When attending their biology
classes, students bring their perceptions, prejudices, and
former experiences in conflict with the scientific facts.
This situation causes various problems to arise during
their biology classes. Keeping knowledge or conceptual
frames of the students in line with the scientific facts can
only be possible with effective conceptual teaching.
There are a number of techniques used to determine
conceptual understanding and misconceptions of
students. Open-ended questions, two-tier diagnostic
tests, interviews, and drawings may be given as exam-
ples of these techniques. Using drawings to access
student’s thinking has been a feature of educational
research. Students can present a broad spectrum of
ideas through drawings (Rennie and Jarvis, 1995).
Drawings have been used broadly in science education
studies of students’ conceptual understanding (Ben-Zvi
Assaraf and Orion, 2005). It is recognized that drawings
expose students’ true understanding and conceptuali-
zation of basic scientific ideas and concepts. This is in
contrast to what is exposed by standard written texts,
where students can repeat what they learned in class
without revealing their misconceptions (Scherz and Oren,
2006). Student drawings in the area of biology can
provide useful insight into common misconceptions or
alternative conceptions (Bahar et al., 2008; Bowker,
2007; Kose, 2008; Prokop and Fanèovièová, 2006). As a
technique for exploring ideas, drawing taps holistic
understanding and prevents students from feeling
constrained by attempting to match their knowledge with
that of the researcher (White and Gunstone, 2000). Thus,
by using simple drawings, biology educators can gather
Dikmenli 237
Figure 1. Example of level 2 (non-representational drawing).
large amounts of data on the mental models students
have about scientific concepts.
Purpose
The purpose of this study was to identify biology student
teachers’ misconceptions of cell divisions using drawings
and interviews. This study focuses on the misconceptions
that biology student teachers possess about the cell
division processes and both the content and scope of
these misconceptions.
METHODOLOGY
Participants
A total of 124 student teachers, who were studying to become
secondary biology teachers at the Faculty of Education in Selcuk
University in Turkey, participated in this study. The average age of
students was 22.3 years (range 21 - 25). The majority of students
were females (76 of 124). However, this study was not focused on
gender differences. In the literature no high gender differences
were found in this field (Kibbos et al., 2004). Thus, the gender
difference was not examined in this study. Participants previously
had studied cell division in cytology, genetics, and molecular
biology, as a school subject during various semesters. Research
was conducted in October, 2008.
Data collection
Biology student teachers’ understanding of the mitosis and meiosis
was examined by two different methods not mutually exclusive: 1.)
students’ drawings and 2.) individual interviews. The drawing
method was chosen to enable a deep, distinctive insight into the
students’ understanding (Rennie and Jarvis, 1995). The participa-
ting students were asked to draw mitosis and meiosis in a cell on a
blank piece of A4-sized paper. The participants were informed
about the drawing method before this application. Also some
practices were applied about this method. In addition, individual
interviews were conducted about the detailed subjects with 15
randomly chosen students who demonstrated misconceptions. The
purpose was to check the validity of the interpretation of the
drawings. In the interview, these students were asked to respond to
questions like “What are chromosomes?,” “When does DNA
replication occur in a cell?,” “What are the differences and
similarities between mitosis and meiosis?,” “What happens to the
cell organelles during the cell division process?,” “How do the
chromosomes act during mitosis and meiosis?.” Their responses
are given below by comparing with the drawings.
Analysis
All the drawings were analyzed independently by the researcher
and three lecturers in biology. The analyzing results were
compared; the differences about a few cases were opened for
discussion and then a final decision about the analyzing was made.
Students’ responses to the drawing activity were analyzed, using a
coding framework prepared by Kose (2008) and Reiss and
Tunnicliffe (2001). Using this framework, five levels of conceptual
understanding were identified for this investigation-no drawing, non-
representational drawings, drawings with misconceptions, partial
drawings, and comprehensive representation drawings. Details of
the levels were as follows:
Level 1: No Drawing: Students replied, “I don’t know,” or no
response was given to the statement.
Level 2: Non-Representational Drawings: These drawings included
identifiable elements of cell division. Also the responses, which
included diagrams or formulations instead of the drawings, were
evaluated in this category (See Figure 1).
Level 3: Drawings with Misconceptions: These types of drawings
showed some degree of understanding on cell division concepts,
but also demonstrated some misconceptions (Figures 2a and b).
Level 4: Partial Drawings: The drawings in this category
demonstrated partial understanding of the concepts. They included
elements of the cell division like prophase, metaphase, anaphase,
telophase, etc. (Figure 3).
Level 5: Comprehensive Representation Drawings: Drawings in
this category were the most competent and realistic diagrams of cell
division (Figure 4). These drawings showed a sound understanding
and contained seven or more elements of the validated response
for this particular statement (Table 1).
RESULTS
This study was conducted to determine biology student
238 Sci. Res. Essays
Figure 2a. Example of level 3 (drawing with misconception).
Figure 2b. Example of level 3 (drawing with misconception).
Figure 3. Examples of level 4 (partial drawing).
teachers’ conceptual understandings and misconceptions
of cell division using drawings and interviews. The data
obtained from drawings were analyzed according to
criteria mentioned above and demonstrated in Figure 5.
When Figure 5 is examined, it is seen that 46% of
these students produced drawings with misconceptions
(level 3) related to mitosis and 54% of them produced
drawings with misconceptions related to meiosis. These
findings reveal the fact that almost half of these students
possess various misconceptions related to mitosis and
meiosis. The proportion of partial drawings (level 4) is
determined as 19 and 16% for mitosis and meiosis,
respectively. In addition, it is further determined that 28%
of these students produced comprehensive representa-
tion drawings (level 5) for mitosis and 13% for meiosis.
Furthermore, it is seen that 5% of these students
produced non-representational drawings (level 2) for
Dikmenli 239
Figure 4. Examples of level 5 (comprehensive representation drawing).
25
46
19
28
4
13
54
16 13
0
10
20
30
40
50
60
No drawing Non-
representational
drawings
Drawings with
misconceptions
Partial drawings Comprehensive
representation
drawings
Percent variation (%)
Mitos is
Meios is
Figure 5. Biology student teachers’ understandings of the cell division as shown in their drawing
mitosis and 13% for meiosis. These proportions indicate
that meiosis is more complicated and a difficult topic to learn for these students, when compared to mitosis.
These results show that less than half of these students
240 Sci. Res. Essays
Table 1. The most frequent elements for mitosis and meiosis drawn by biology student teachers.
Elements for mitosis n % Elements for meiosis n %
Karyokinesis (Prophase, Metaphase, etc.) 115 93 Karyokinesis (Prophase, Metaphase, etc.) 112 90
Chromosome 110 89 Homologous chromosomes 98 79
Chromatids 100 80 DNA Replication 83 67
DNA Replication 87 70 Diploid (2n) / Haploid (n) 77 62
Interphase 85 69 Chromatids 64 52
Nuclear envelope 84 68 Interphase 61 49
Spindle fibers 77 62 Chromatin 53 43
Centrosome / Centrioles 72 58 Spindle fibers 46 37
Chromatin 54 44 Equatorial plate 39 31
Nucleolus 40 32 Crossing-over 30 24
Cytokinesis 29 23 Nuclear envelope 23 19
Equatorial plate 20 16 Nucleolus 18 15
Sister chromatids 14 11 Centrosome / Centrioles 15 12
Centromere 9 7 Cytokinesis 10 8
Cell cycle 4 3 Centromere 5 4
possess comprehensive or partial knowledge related to
cell division, in particular, to meiosis.
The elements recurring most frequently on the draw-
ings as related to mitosis are presented in Table 1, which
shows that more than half of these students concentrate
on elements like karyokinesis, chromosome, chromatids,
DNA replication, interphase, nuclear envelope, spindle
fibers, and centrosome/centrioles. On the other hand, it is
reported that less than half of these students show
elements like chromatin, nucleolus, equatorial plate,
sister chromatids, centromere, and cell cycles in their
drawings. These results demonstrate these students
mainly focus on the stages of the karyokinesis and the
events occurring at these stages related to mitosis.
When the elements related to meiosis are taken into
consideration, it is found that more than half of the
students concentrate on elements like karyokinesis,
homologous chromosomes, DNA replication, diploid/
haploid, and chromatids. On the other hand, it is reported
that less than half of the students display elements like
interphase, chromatin, spindle fibers, equatorial plate,
crossing-over, nuclear envelope, nucleolus, centrosome/
centrioles, cytokinesis, and centromere in their drawings
(Table 1). Analysis of the elements related to mitosis and
meiosis shows that these student teachers mostly
considered elements related to the karyokinesis for an
animal cell and disregarded the karyokinesis for a plant
cell. For example, almost none of these student teachers
noted the cytokinesis or cell plate in a plant cell, except
for a few students.
Twenty-four misconceptions were determined in total
as a result of the analyses on biology student teachers’
drawings. These misconceptions are given in Table 2.
The drawing method provided detailed information on
determination of the misconceptions related to cell
division. For example, in their drawings, thirty-three
students indicated the number of chromosomes remained
the same at the end of meiosis-I and halved at the end of
meiosis-II (Figure 2a). Moreover, in their drawings, ten
students indicated the number of chromosomes is halved
at the end of mitosis (Figure 2b). These results showed
that biology student teachers possess some misconcep-
tions about mitosis and meiosis, in particular, about the
number of chromosomes.
In addition, many misconceptions were determined
during interviews with 15 randomly chosen students who
demonstrated misconceptions. A majority of the miscon-
ceptions obtained from the interviews were consistent
with the misconceptions detected on the drawings.
Misconceptions obtained from the interviews are given in
Table 3. Some of the significant misconceptions obtained
from the interviews were as follows. Eleven of the
interviewed students mentioned the organelles, such as
mitochondria and chloroplasts, dissolve and vanish
during cell division, and then are reformed. It is further
seen that such students also believe the alterations
occurring at the nucleus in karyokinesis also occurred at
the organelles, such as mitochondria and chloroplasts in
a similar manner. Three of these students mentioned the
centrioles are found in the nucleus of a cell. This
misconception was also encountered in the drawings of
14 students (Table 1, Figure 6).
Nine of the interviewed students mentioned DNA
replication occurs in the prophase, while two of these
students mentioned DNA replication occurs between the
prophase and the metaphase during cell division. These
students did not mention the DNA molecule replicates at
the S stage of the interphase prior to cell division. These
misconceptions obtained from the interviews were also
encountered in a majority of the drawings (Figure 7).
Dikmenli 241
Table 2. Misconceptions about cell division obtained from the drawings.
Misconceptions n
1 Interphase is the resting phase of mitosis. 47
2 DNA replication occurs in prophase during the process of cell division. 46
3 The chromosome number is doubled in the prophase of mitosis and halved in the anaphase of mitosis. 40
4 Chromosomes and chromatids are essentially the same thing. 35
5 The chromosome number remains the same during meiosis-I and is halved during meiosis-II. 33
6 In mitosis, homologous chromosomes separate in the anaphase. 23
7 Diploid (2n) cells are formed as a result of meiosis. 23
8 A chromosome has always two chromatids during cell division. 21
9 Sister chromatids do not separate in mitosis. 20
10
Homologous chromosomes are separated at the anaphase-II of the meiosis. 20
11
At a cell whose number of diploid chromosomes is 4, there are two chromosomes—each comprises of two chromatids.
19
12
Sister chromotides are separated from each other at the anaphase-I of the meiosis. 16
13
Sister chromotides only separate with meiosis. 16
14
Centrioles are found in the nucleus of a cell. 15
15
DNA replication occurs between meiosis-I and meiosis-II. 13
16
Spindle fibers are formed by centromere. 12
17
DNA replication occurs between prophase and metaphase during the process of cell division. 11
18
The number of chromosomes is halved after mitosis. 10
19
The meiosis of a cell with 2n = 4 chromosomes produces cells with a single chromosome. 9
20
Crossing over occurs at the metaphase-I of the meiosis. 7
21
The number of chromosomes remains the same after meiosis. 6
22
The number of chromosomes is doubled after mitosis. 5
23
DNA replication occurs between anaphase and telophase during the process of cell division. 4
24
DNA replication occurs in cytokinesis during the process of cell division. 4
Table 3. Misconceptions about cell division obtained from the interviews.
Misconceptions
1 The organelles, such as mitochondria and chloroplasts, dissolve and vanish during cell division and then are reformed.
2 Centrioles are found in the nucleus of a cell.
3 DNA replication occurs in the prophase during the process of cell division.
4 DNA replication occurs between prophase and metaphase during cell division.
5 Interphase is the resting phase of mitosis.
6 DNA replication takes place only in the meiosis process.
7 Chromosomes are formed as a result of shrinkage and thickening of spindle fibers.
8 In mitosis, homologous chromosomes separate in the anaphase.
9 The chromosome number is doubled in the prophase of mitosis and halved in the anaphase of mitosis.
10
Meiosis occurs in the reproductive (sperm or egg) cells.
11
A chromosome has always two chromatids during cell division.
12
Centrioles are replicated during the prophase stage.
13
Diploid (2n) cells are formed as a result of meiosis.
14
During cell division, each centriole of the centrosome is separated and moves towards the opposite poles.
15
Spindle fibers are formed from centromers.
16
The centrosome and centrioles is essentially the same thing.
17
The sister chromatids are homologous chromosomes.
Seven of these students mentioned the interphase is
the resting phase of mitosis. These students did not mention the interphase is a phase of cell cycle. This
misconception was not only encountered during the inter-
242 Sci. Res. Essays
Figure 6. A drawing of misconception of “centrioles are found in the nucleus of a cell”
Figure 7. A drawing of misconception of “DNA replication occurs between prophase and metaphase during cell
division”.
views, but also from the drawings (Figure 8).
Six of the interviewed students mentioned the chromo-
some number is doubled in the prophase of mitosis and
halved in the anaphase of mitosis. This misconception
was also encountered from the drawings (Figure 9). It
was observed that a majority of the misconceptions
obtained from the interviews consistent with the miscon-
ceptions determined from the drawings. This fact consoli-
dated the validity of the misconceptions obtained from the
drawings. For example, five of the interviewed students
indicated that typically one chromosome always has two
chromatids during the cell division process. These
students believed that typically one chromosome comp-
rises of two chromatids and the chromosome is replicated
Dikmenli 243
Figure 8. A drawing of misconception of “interphase is the resting phase of the mitosis”.
Figure 9. A drawing of misconception of “the chromosome number is doubled in the
prophase of mitosis and halved in the anaphase of mitosis”.
in this form. This misconception was not only encoun-
tered during the interviews, but also from 21 of the
student’s drawings (Figure 10). In addition, four of the
interviewed students indicated the diploid cells are
formed as a result of meiosis. This misconception was
also encountered from 23 of the student’s drawings
244 Sci. Res. Essays
Figure 10. A drawing of misconception of “a chromosome has always two chromatids
during cell division”.
(Figure 11).
DISCUSSION
Utilization of student drawings and interviews together
with an appropriate sample size ensured determination of
numerous alternative points of view that biology student
teachers possess in relation to cell division. The findings
gained from the drawings and the interviews show that a
majority of the students cannot establish accurate
relationships between cell cycle and cell division. It was
observed that the students participating in this study are
not able to establish conceptual relations associated with
mitosis and meiosis, and possess a complicated
knowledge frame. For example, these students were
observed to be in conceptual confusion, particularly
between the concepts related to the cell cycle-cell
division, mitosis-meiosis, haploid-diploid cells, sister
chromatids-homologous chromosomes, centrosome-
centrioles-centromere, and spindle fibers-chromatin-
chromatid-chromosome. These findings support the studies
Dikmenli 245
Figure 11. A drawing of misconception of “diploid cells are formed as a result of meiosis”.
conducted previously in regards to this subject matter
(Kindfield, 1994; Smith, 1991).
Analysis of the drawings revealed that a conceptual
understanding of these biology student teachers is
relatively weak, particularly regarding the behaviors of the
chromosomes, chromosome numbers, alterations occur-
ring at the organelles, stages of the cell division, and the
DNA replication during mitosis and meiosis. These
findings are surprisingly since the subjects of mitosis and
meiosis are incorporated into primary, secondary, and
undergraduate curriculums. Some of the misconceptions
indicated in this study resembled the misconceptions
mentioned for previous studies conducted in Turkey and
other countries on some periods of school life (Atilboz,
2004; Brown, 1990; Flores et al., 2003; Kindfield, 1991;
Lewis et al., 2000; Lewis and Wood-Robinson, 2000;
Marbach-Ad and Stavy, 2000; Riemeier and
Gropengießer, 2008; Saka et al., 2006; Smith, 1991;
Yesilyurt and Kara, 2007; Yilmaz et al., 1998). But, it was
also observed that some misconceptions indicated in this
study emerged for the first time. Some of these new
misconceptions include: “DNA replication occurs between
prophase and metaphase during the process of cell
division” (Figure 7), “A chromosome has always two
chromatids during cell division” (Figure 10), “Interphase is
the resting phase of mitosis” (Figure 8), “The chromo-
some number remains the same during meiosis-I and is
halved during meiosis-II” (Figure 2a), “Centrioles are
found in the nucleus of a cell” (Figure 6), “The organelles,
such as mitochondria and chloroplasts, dissolve and
vanish during cell division and then are reformed,”
“Chromosomes are formed as a result of shrinkage and
thickening of spindle fibers.” The existence of these
misconceptions, despite the fact students are educated
with various education techniques at the university, show
that such misconceptions are extremely resistant against
change (Bahar, 2003; Wandersee et al., 1994).
Therefore, the teachers at the primary and secondary
education levels, and the lecturers at the university
assume very important roles regarding employment of
alternative teaching strategies to eliminate or at least
minimize such misconceptions. Effective teaching
methods must be used to eliminate or minimize these
misconceptions that the university students possess.
Otherwise, the new teachers will continue teaching these
misconceptions and the cycle is not broken. Graphical or
visual tools, such as conceptual maps, conceptual
networks, and conceptual change strategies, such as
conceptual change texts, are the methods more likely to
reduce or eliminate misconceptions of students (Novak
and Canas, 2004; Tekkaya, 2003).
Biology student teachers are confused about the
concepts related to mitosis and meiosis. These findings
overlap with the findings of the study conducted by Flores
et al. (2003). The misconceptions related to mitosis and
meiosis might also originate from the textbooks and
explanations given in the classrooms. Cook (2008)
indicates that some illustrations contained in textbooks
related to meiosis lead to understanding difficulties for
students. It is a well-known fact that it is not an easy task
to eliminate these misconceptions by means of traditional
teaching methods. An alternative way for overcoming
problems related to these misconceptions might be to
employ computer-aided educational materials for biology
classes (Cepni et al., 2006; Yesilyurt and Kara, 2007). In
addition, many studies suggest that the use of models in
246 Sci. Res. Essays
biology greatly enhances student understanding of cell
division (Clark and Mathis, 2000; Pashley, 1994).
Moreover, Chinnici et al. (2004) report that to procure
students to act as “human chromosomes” through role-
playing mitosis and meiosis is an effective method to
enhance learning of these important processes for
students.
Another source of the misconceptions might be the
terminology used during teaching. For instance, the
misconceptions determined under the scope of this study,
such as “Spindle fibers are formed by centromere (Table
2),” “Chromosome and chromatid are essentially the
same thing (Table 2),” and “Centrosome and centrioles
are essentially the same thing (Table 3),” clearly indicate
that students are confusing terms, such as chromatid -
chromosome, centrosome - centrioles, centrosome
centromere, with each other. As a matter of fact, it is
known from previous studies that the conflicting terms
such as “divide, replicate, copy, share, split” used for
identification of cell division processes in terms of genetic
information and chromosomes are being confused by the
students (Lewis and Wood-Robinson, 2000). Therefore, it
is understood that it shall be necessary to pay specific
attention to the terminology by the teachers and textbook
authors in regard to education on cell division.
Conclusions and Recommendations
This study revealed biology student teachers have a
series of significant problems regarding the concepts of
cell division and structuring of such concepts in a
meaningful manner. These problems are mainly associa-
ted with meiosis rather than mitosis. The students
confuse the stages of the cell division process and the
events occurring at these stages with each other. Miscon-
ceptions revealed in this study showed that students
have conceptual difficulties in explaining the phenomena
that require a good understanding of cell division con-
cepts, such as cell cycle-cell division, mitosis-meiosis,
haploid-diploid cells, sister chromatids-homologous
chromosomes, centrosome-centrioles, and spindle fibers-
chromatin. The students mostly focus on cell division with
animal cells and disregard cell division with plant cells.
In summary, biology student teachers have many
misconceptions related to cell division. Misconceptions
are often resistant to elimination through conventional
teaching strategies (Bahar, 2003; Wandersee et al.,
1994). Therefore, new teaching strategies, such as con-
ceptual maps, conceptual networks, semantic features
analysis and conceptual change texts (Novak and Canas,
2004; Tekkaya, 2003), are chosen and students’
conceptions are taken into account when preparing
lessons. Student-centered learning activities should be
implemented with a conceptual development towards the
scientific concept (Riemeier and Gropengießer, 2008).
Lecturers must be aware of students’ misconceptions, as
well as their sources, in order to improve teaching of cell
division. In addition, for students to understand cell
division, related subordinate concepts must be mastered.
Biology curricula developers should consider students’
difficulties in understanding cell division concepts and
take students’ perspectives into account. Moreover,
employment of educational materials, such as computer
technologies (Cepni et al., 2006; Yesilyurt and Kara,
2007) and models (Clark and Mathis, 2000; Pashley,
1994) for teaching the cell division processes should
assist these students to concretize abstract concepts.
The study determined that students can reveal what
they know and understand through drawings. The inter-
pretation of the drawings and interviews gave insight into
students’ understanding about cell division and demon-
strated that drawings can be an effective method of
probing some aspects of their learning difficulties. The
literature supports this finding and suggests that students
drawings are effective in identifying their biological
misconceptions (Bahar et al., 2008; Bowker, 2007; Kose,
2008; Reiss and Tunnicliffe, 2001). In this respect, it is
recommended employment of the drawing method for
determination of the misconceptions and learning
difficulties for further studies.
REFERENCES
Atilboz NG (2004). 9th Grade students’ understanding levels and
misconceptions about mitosis and meiosis. J. Gazi Edu. Faculty 24
(3): 147-157.
Bahar M (2003). Misconceptions in biology education and conceptual
change strategies. Edu. Sci.: Theory Pract. 3(1): 55-64.
Bahar M, Ozel M, Prokop P, Usak M (2008). Science student teachers’
ideas of the heart. J. Baltic Sci. Edu. 7(2): 78-85.
Ben-Zvi Assaraf O, Orion N (2005). Development of system thinking
skills in the context of Earth system education. Res. Sci. Teach. 42
(5): 518-560.
Bowker R (2007). Children’s perceptions and learning about tropical
rainforests: An analysis of their drawings. Environ. Edu. Res. 13(1):
75-96.
Brown CR (1990). Some misconceptions in meiosis shown by students
responding to an advanced-level practical examination question in
biology. J. Bio. Edu. 24(3): 182-186.
Cepni S, Tas E, Kose S (2006). The effects of computer-assisted
material on students’ cognitive levels, misconceptions and attitudes
towards science. Comp. Edu. 46(2): 192-205.
Chinnici JP, Yue JW, Torres KM (2004). Student as “human
chromosomes” in role-playing mitosis and meiosis. The Am. Bio.
Teach. 66(1): 35-39.
Clark DC, Mathis PM (2000). Modeling mitosis and meiosis, a problem-
solving activity. The Am. Bio. Teach. 62(3): 204-206.
Cook M (2008). Students’ comprehension of science concepts depicted
in textbook illustrations. Elect. J. Sci. Edu. 12: 1.
Cordero RE, Szweczak CA (1994). The developmental importance of
cell division. The Am. Bio. Teach. 56(3): 176-179.
Flores F, Tovar M, Gallegos L (2003). Representation of the cell and its
processes in high school students: An integrated view. Int. J. Sci.
Edu. 25(2): 269-286.
Kibbos JK, Ndirangu M, Wekesa EW (2004). Effectiveness of a
computer-mediated simulations program in school biology on pupils’
learning outcomes in cell theory. J. Sci. Edu. Technol. 13(2): 207-213.
Kibuka-Sebitosi E (2007). Understanding genetics and inheritance in
rural schools. J. Bio. Edu. 41(2): 56-61.
Kindfield ACH (1991). Confusing chromosome number and structure: A
common student error. J. Bio. Edu. 25(3): 193-200.
Kindfield ACH (1994). Understanding a basic biological process: Expert
and novice models of meiosis. Sci. Edu. 78(3): 255-283.
Kose S (2008). Diagnosing student misconceptions: Using drawings as
a research method. World Appl. Sci. J. 3(2): 283-293.
Kruger D, Fleige J, Riemeier T (2006). How to foster an understanding
of growth and cell division. J. Bio. Edu. 40(3): 135-140.
Lewis J, Leach J, Wood-Robinson C (2000). Chromosomes: The
missing link - young people’s understanding of mitosis, meiosis and
fertilization. J. Bio. Edu. 34(4): 189-199.
Lewis J, Wood-Robinson C (2000). Genes, chromosomes, cell division
and inheritance - do students see any relationship? Int. J. Sci. Edu.
22(2): 177-195.
Marbach-Ad G, Stavy R (2000). Students cellular and molecular
explanations of genetic phenomena. J. Bio. Edu. 34(4): 200-205.
Novak JD, Canas A (2004). Building on new constructivist ideas and
Cmap tools to create a new model for education. Proceedings of the
First Int. Conference on Concept Mapping, Pamplona, Spain.
Oztas H, Ozay E, Oztas F (2003). Teaching cell division to secondary
school students: An investigation of difficulties experienced by
Turkish teachers. J. Bio. Edu. 38(1): 13-15.
Pashley M (1994). A-level students: Their problems with gene an allele.
J. Bio. Edu. 28(2): 120-126.
Pfundt H, Duit R (2004). Bibliography: Students’ alternative frameworks
and science education. University of Kiel Institute for Science
Education: Kiel, Germany.
Prokop P, Fanèovièová J (2006). Students’ ideas about human body:
Do they really draw what they know? J. Baltic Sci. Edu. 2(10): 86-95.
Reiss MJ, Tunnicliffe SD (2001). Students’ understandings about
human organs and organ systems. Res. Sci. Edu. 31: 383-399.
Rennie LJ, Jarvis T (1995). English and Australian children’s
perceptions about technology. Res. Sci. Technol. Edu. 13(1): 37-52.
Riemeier T, Gropengießer H (2008). On the roots of difficulties in
learning about cell division: Process-based analysis of students’
conceptual development in teaching experiments. Int. J. Sci. Edu.
30(7): 923-939.
Dikmenli 247
Saka A, Cerrah L, Akdeniz AR, Ayas A (2006). A cross-age study of the
understanding of three genetic concepts: How do they image the
gene, DNA and chromosome? J. Sci. Edu. Technol. 15(2): 192-202.
Scherz Z, Oren M (2006). How to change students’ images of science
and technology. Sci. Edu. 90(6): 965-985.
Smith MU (1991). Teaching cell division: Student difficulties and
teaching recommendations. J. Coll. Sci. Teach. 21(1): 28-33.
Smith MU, Kindfield ACH (1999). Teaching cell division: Basics and
recommendations. The Am. Bio. Teach. 61(5): 366-371.
Stewart J, Dale M (1989). High school students’ understanding of
chromosome/gene behavior during meiosis. Sci. Edu. 73(4): 501-521.
Tekkaya C (2003). Remediating high schools’ misconceptions
concerning diffusion and osmosis through concept mapping and
conceptual change text. Res. Sci. Technol. Edu. 21(1): 5-16.
Wandersee JH, Mintzes JJ, Novak D (1994). Research on alternative
conceptions in science. In D.L. Gabel (Ed.), Handbook of research on
science teaching and learning. New York: Macmillan pp. 177-210
White R, Gunstone RF (2000). Probing understanding. London, UK,
Falmer Press.
Yesilyurt S, Kara Y (2007). The effects of tutorial and edutainment
software programs on students’ achievements, misconceptions and
attitudes towards biology on the cell division issue. J. Baltic Sci. Edu.
6(2): 5-15.
Yilmaz O, Tekkaya C, Geban O, Ozden Y (1998). Lise-1. Sinif
ogrencilerinin hcre bolunmesi unitesindeki kavram yanilgilarinin tespiti
ve giderilmesi, III. Ulusal Fen Bilimleri Egitimi Sempozyumu, 23-25
Eylul 1998, KTU, Trabzon (in Turkish).
... Por tanto, trabajar la habilidad de cuestionar y cuestionarse a través del discurso es esencial durante el aprendizaje de Biología (Bravo-Torija et al. 2016;NRC 2013); y más aún cuando se abordan contenidos a escala microscópica, como la división celular, que suscitan muchos interrogantes por percibirlos tan alejados de nuestra vida cotidiana (Esquivel-Martín, Pérez-Martín y Bravo-Torija 2021). Tanto es así que a los alumnos les cuesta modelizar la mitosis y la meiosis como procesos continuos; desconocen cómo evolucionan algunas de las estructuras que intervienen; y tienen problemas para identificar sus diferentes etapas en imágenes reales, sin conseguir relacionarlas con las representaciones de referencia (Dikmenli 2010). Por ello, desde la investigación educativa se están lanzando propuestas que pretenden mejorar la enseñanzaaprendizaje de la división celular durante la ESO. ...
... Con respecto al contenido sobre división celular evaluado, hay más preguntas sobre mitosis (82), que sobre meiosis (58), existiendo otras 48 que demandan conocer ambos procesos. Este aparente desequilibrio favorece al alumnado, ya que presentan más dificultades de comprensión e ideas alternativas sobre el modelo de meiosis (Dikmenli 2010), lo que se ve cuando llegan a la universidad (Rodríguez, Fradkin y Castañeda 2018). Además, llama la atención que el propio examen contenga errores, preguntando sobre meiosis con enunciados como: «Con relación al ciclo celular: […]» (p. ...
Article
Full-text available
La escolarización debería alfabetizar científicamente a la ciudadanía para tomar decisiones con criterio sobre cuestiones sociocientíficas, como el uso de pseudoterapias para tratar el cáncer. Por ello, se necesita conocer la forma de evaluar lo aprendido en todas las etapas educativas. Sin embargo, apenas hay estudios que consideren cómo se evalúa el aprendizaje de Biología adquirido durante el Bachillerato en las pruebas de acceso a la universidad (EvAU). De manera que, en este trabajo, se analiza la demanda cognitiva requerida para responder las 188 preguntas sobre un proceso biológico tan relevante como la división celular, que han sido formuladas en los exámenes EvAU de Biología de la Comunidad de Madrid desde 2002 hasta 2019; distinguiendo entre preguntas de producto, de relato y de proceso. Los resultados muestran un predominio de las preguntas de relato y de producto, con menor demanda cognitiva, viéndose una clara tendencia a aumentar las segundas hasta 2016. Además, algunos enunciados se repiten, centrándose principalmente en: mitosis, células animales, dinámica cromosómica o etapas como la anafase; obviando estructuras y momentos del proceso importantes, como el huso acromático o la prometafase. Se discuten posibles mejoras como la inclusión de preguntas de proceso que demanden tomar decisiones.
... Scientist Spotlights as Curricular Interventions to Counter Stereotypes, Promote Students' Science Identity, and Change Scientist Representation Societal images of scientists surround students in their everyday lives and in science classrooms, often sending singular and exclusionary messages about who belongs in science that are in fact inaccurate. These images often portray stereotypical images of a scientist, such as a person who is white, male, possibly socially awkward, or perhaps from an affluent background with parents who were college educated or of a higher socioeconomic status (Mead and Métraux, 1957;Dikmenli, 2010). These ideas are also present in students' views of scientists. ...
... Non-stereotype descriptions were those that went against the stereotypes and included phrases such as "anyone can be a scientist or many types of people can be a scientist." To categorize stereotypical scientist names, we used a previously identified list of stereotypical scientists (Dikmenli, 2010), which included "Albert Einstein, Isaac Newton, and Charles Darwin." Nonstereotypical scientist names were considered any named individuals not listed as a stereotypical scientist. ...
Article
Full-text available
Scientist Spotlights-curricular materials that employ the personal and professional stories of scientists from diverse backgrounds-have previously been shown to positively influence undergraduate students' relatability to and perceptions of scientists. We hypothesized that engaging students in authoring Scientist Spotlights might produce curricular materials of similar impact, as well as provide a mechanism for student involvement as partners in science education reform. To test this idea and investigate the impact of student-authored Scientist Spotlights, we developed a service-learning course in which teams of biology students partnered with an instructor to develop and implement Scientist Spotlights in a biology course. Results revealed that exposure to three or four student-authored Scientist Spotlights significantly shifted peers' perceptions of scientists in all partner courses. Interestingly, student-authored Scientist Spotlights shifted peers' relatability to scientists similarly among both white students and students of color. Further, student authors themselves showed increases in their relatability to scientists. Finally, a department-wide survey demonstrated significant differences in students' perceptions of scientist representation between courses with and without student-authored Spotlights. Results suggest that engaging students as authors of inclusive curricular materials and partners in reform is a promising approach to promoting inclusion and addressing representation in science.
... Contrary to what many students may think about their own mastery of the subject, the biology education literature provides ample evidence that students hold numerous misconceptions, incomplete and/or incorrect ideas about this process. [1][2][3][4][5][6][7][8][9] When students do not have deep knowledge about the underlying reasons and concepts linked with meiosis, it hinders their ability to master future concepts in genetics and evolution. We have focused much of our research on understanding how learners conceptualize meiosis and how their mental models of this process differ from that of experts. ...
... Inserts allow for demonstration of "zooming in" to the sequence level, where individual nucleotides can be added. (b) The three types of parts are put together to show the sequence similarity of homologous chromosomes T A B L E 1 Learning objectives were developed based on research about student misconceptions and naïve ideas about meiosis Learning objective Students will be able to: Examples of common novice ideas/misconceptions related to LO LO1 Correctly predict chromosome number at any stage of meiosis.Students incorrectly count chromatids as chromosomes, leading to incorrect conclusions about when chromosome number is changed.6 ...
Article
Many biology students struggle to learn about the process of meiosis and have particular difficulty understanding the molecular basis of crossing over and the importance of homologous pairing for proper segregation. To help students overcome these challenges, we designed an activity that uses a newly developed Chromosome Connections Kit® from 3‐D Molecular Designs to allow learners to explore meiosis at the molecular level. We took a backwards design approach in constructing an effective classroom activity. We developed evidence‐based learning objectives and designed a crossing over activity that targets students' misconceptions and key concepts about meiosis. Assessment questions were designed based on the learning objectives and common student misconceptions. The activity consists of three parts: an interactive introductory video, a model‐based activity, and reflection questions. The activity was first beta‐tested with a small number of students and revised based on feedback. The revised activity was deployed in a mid‐level Cell and Molecular Biology course. Analysis of pre‐/post‐assessment data from students who completed the activity (n = 83) showed strong learning gains on concepts related to ploidy, homology, segregation, and the mechanism and purpose of crossing over. Additionally, students who participated in the activity outperformed nonparticipants on a Genetics assessment about meiosis the following semester. Traditional instruction on meiosis does not help students “see” the underlying molecular mechanisms that drive the processes of homologous pairing and crossing over. Our newly designed model‐based activity helps students explore the molecular level and learn concepts related to ploidy, homology, segregation and crossing over.
... Table 1 The following is an explanation regarding the symbols and the answer scores obtained in the fifth tier, shown in Table 2. Table 2. The explanation regarding the symbols and the 5th tier answer scores is adapted from (Anam et al., 2019;Dikmenli, 2010;Köse, 2008) No. Symbol Description Score (%) Based on the description of the misconceptions experienced by students in Thermodynamics material (Purnama & Fakhruddin, 2018), so this research reports the results of the development of an electronic diagnostic instrument for thermodynamics in a five-tier format based on google form, to find a conception level profile and trace the existence of misconceptions and their causes, considering that until now this instrument has not been available. ...
Article
Full-text available
The learning process can not be separated from the assessment activities. Google form is one of the assessment applications used during Covid-19 pandemic. In learning physics, students often have difficulty understanding concepts, leading to misconceptions. Student interview results showed that thermodynamics is a complex material. This research aims to develop a five-tier diagnostic test based on google form to identify the conception levels and track misconceptions in thermodynamic material. Research & Development method with eight stages, namely potential and problems, information gathering, instrument design, design validation, design revision, trial, instrument revision, and research test, was applied to obtain the instrument. The feasibility of the test was met by the results of validity and reliability tests. A total of 12 questions were successfully developed and declared valid and reliable at the value of 0.601. The research sample consisted of 47 students of 11th Grade of MAN 1 Bojonegoro. The results showed that the google form-based five-tier e-diagnostic test developed was able to identify conception levels and track students' misconceptions on thermodynamic material. The highest conception levels were dominated by Lack of Knowledge and the presence of misconceptions reached 28.33% in low category. Students' misconceptions are caused by wrong reasoning, intuition, humanistic thinking, preconceptions, and associative thinking. This five-tier diagnostic instrument can be used by physics teachers as an assessment instrument in physics learning. In addition, to fulfilling the evaluation and assessment objectives achievement, this instrument provides convenience in implementation, documentation, and track the causes of students' difficulties in understanding thermodynamic concepts.
... In the interviews with the students, some students have stated that they come to understand the subjects that they previously did not understand much better while drawing. Dikmenli (2010) determined in his study that students could reveal what they know and understand with drawings. Although there are many studies on the effectiveness of the drawing methods in teaching of other branches of science, the effectiveness of the drawing method in the teaching wood anatomy should also be investigated. ...
Article
Full-text available
The teaching of wood anatomy is difficult because of the Latin and foreign terminology and the great number of concepts, definitions, terms, and topics that must be learned and that pose difficulties in understanding for most students. The aim of this study was to describe developed traditional methods and adapt new methods in order to explain wood anatomy more clearly to students in both online and face-to-face education. The teaching of the Wood Structure and Identification course at the Vocational School of Forestry was observed and evaluated over the period of two academic terms (one during the Covid-19 pandemic). Teaching methods used in the wood anatomy course were described in detail. Lesson materials and homework were evaluated. When the usual methods were diversified and enriched with visuals and samples brought to the classroom, the students showed more interest in the lesson. As a result of the student drawing and modelling assignments, the lesson was reviewed and reinforced, which enabled the students to focus on the subject and consequently, to understand and learn more easily. It has determined that all teaching methods can be applied easily in both education periods, except using real wood samples method in online education.
... Por ejemplo, se utilizan términos como pili en las células procariotas que no aparecían en el pretest, probablemente por estarse confundiendo inicialmente con los cilios eucariotas (Figura 1A). Nuestro estudio también detectó dificultades relacionadas con la terminología científica, adicionales a las ya descritas por Dikmenli (2010). Por tanto, la intervención incita a los estudiantes a juzgar críticamente los materiales educativos. ...
Conference Paper
Full-text available
Conocer la estructura celular es vital para entender procesos como la nutrición, pero muchos estudiantes acaban la escolaridad obligatoria sin hacerlo. Pocos trabajos abordan este problema evaluando dibujos de la célula. En concreto, analizamos la evolución del conocimiento sobre la escala, tridimensionalidad y composición celular en los dibujos de 21 alumnos de 4º de ESO, antes y después de una intervención basada en un relato sobre el origen y evolución de la vida terrestre. Los resultados muestran mejoría en su percepción sobre la célula, al aumentar el número de estudiantes que: respetan la escala intercelular eucariota-procariota e intracelular eucariota; integran la tridimensionalidad al dibujar el corte de la célula eucariota; y alcanzan el nivel de representación total. Consideramos que el relato es una herramienta útil para modificar los modelos de célula del alumnado.
... As a result, there is a difficulty in conceptual understanding about "meiosis." Specifically, learners misinterpret chromosomes all throughout the stages of meiosis like incorrect depictions of the sister chromatids (Dikmenli, 2010;Newman et al., 2012). ...
Article
Full-text available
This study generally aims to design context-based video instruction in accordance to TPACK framework in order to enhance the conceptual understanding of the students with regards to cell biology. The current study assessed the level of conceptual understanding of 73 Grade 11 student-respondents of Quezon Science High School in cell biology prior to the utilization of context-based video instruction. It sought to test the significant difference between the pretest and posttest scores in the said discipline. This study identified the level of acceptability of the context-based video instruction as perceived by the student-respondents in terms of learning objectives, accuracy, appeal, clarity, and usability. The respondents are enrolled in STEM strand of Senior High School, S.Y. 2020 – 2021. Questionnaires and the context-video instruction were developed and validated to assess and evaluate the research objectives of this study. The topics in cell biology obtained an overall MPS value of 31.15%. It means that the student-respondents have specific misconceptions about the different concepts in the said topic prior to the utilization of the said learning digital resources. The appropriateness of the language, general appearance of the teacher, quality of video, lighting, animation, and video transitions were some of the parameters considered in designing the video lectures. The overall t-value of 59.57 is greater than the tabular value of 1.99. It implies that the developed context-based video instruction in enhancing the conceptual understanding in cell biology is a valid tool in the teaching-learning process. Furthermore, the developed context-based video instruction in enhancing the conceptual understanding is commendable for use in terms of learning objectives, clarity, accuracy, appeal, and usability.
... Inspired by our experience with DTL as instructors in Buddhist monastic universities, we posit that DTL can be relevant across educational contexts. Visualizations of mental models reveal for both learner and teacher what is clear and messy, as students make sense of new concepts (Dikmenli, 2010). Both disorderly writing and drawing can reveal disorderly thinking. ...
Article
Full-text available
Students enter biology classrooms with ideas about the natural world already formed. Teachers can help students construct new knowledge by using active, culturally relevant pedagogy and by making space in their lesson for students to reveal, challenge, and/or reconcile their preconceptions with new knowledge. Drawing meets all of these needs. Drawing-to-learn (DTL) allows students to be metacognitive and creative as they generate concrete representations of their abstract conceptions. In this case study of biology classes for Tibetan Buddhist monastic students through the Emory-Tibet Science Initiative, we find that DTL engages students in active learning, allows multi-modal visualization and discourse about mental models, and beyond this, solicits cultural references from both students and teachers.
Article
Novel series of thiopyrano[2,3-d]1,3-thiazole derivatives incorporating arylsulfonate moiety were synthesized and characterized by ¹H NMR, ¹³C NMR, MS, and IR. The synthesized compounds 6a-d, 8a-t, 10a-f, and 11a,b were evaluated for the cytotoxicity activity against four human cancer cell lines concerning mammary gland (MCF7), epithelioid carcinoma (Hela), human prostate cancer (PC3), and Hepatocellular carcinoma (HepG2). Compound 8d showed higher anticancer activity against MCF7 cell line (IC50 = 3.90±0.4 µM) compared to the standard drug doxorubicin (IC50 = 4.17±0.2 µM). Furthermore, compounds 6a has anticancer activity near to the standard drug doxorubicin against MCF7 and Hela cell lines with IC50 = 5.38±0.6 µM, and 7.63±0.8 µM, respectively. On the other hand, compound 8b exhibited an inhibitory effect against tubulin polymerization with an IC50 = 0.832± 0.031 μg/ml, which was similar to the positive control Colchicine (IC50 = 0.810±0.10). The arylsulfonate moiety in 2,4-thiazolidinedithione core exerted a key effect on the anticancer activities of target compounds, according to structure-activity relationships (SARs) and docking studies. In HepG2 cells, compound 8b also caused cell cycle arrest at the G2/M phase and induced apoptosis.
Article
The findings of this research indicate that it is important for teachers to be aware of students' concepts in genetics before they start teaching them. It also showed that once students had resolved any difficulty with the relationship between gene and allele, their performances in genetics showed a significant improvement. This research found that the use of a chromosome model as a conceptual challenge tool was a most effective way of resolving these difficulties, especially if teachers were aware of students' concepts, and had undergone some staff development in the model's use.
Article
Genetics has long been recognized as one of the most important and difficult-to-learn components of the basic biology curriculum. In this paper, I report on a common and rather tenacious student misconception about chromosomes, an accurate understanding of which is of central importance to understanding transmission genetics. Specifically, students often believe that chromosome structure is a function of chromosome number or ploidy. Although common, the presence of this misconception in students' understanding of chromosomes can be quite elusive. Several aspects of standard genetics instruction are cited as potential sources of the ploidy/structure misconception and implications for instruction are discussed.