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Journal of Biological Education
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Unravelling the Central Dogma of Biology in an
active way: a case study
Lucas Fagundes Silveira, Christian Santos Xavier, Maíra Alexandre Perez,
Dandie Antunes Bozza, Lupe Furtado-Alle, Iris Hass & Luciane Viater Tureck
To cite this article: Lucas Fagundes Silveira, Christian Santos Xavier, Maíra Alexandre Perez,
Dandie Antunes Bozza, Lupe Furtado-Alle, Iris Hass & Luciane Viater Tureck (2021): Unravelling
the Central Dogma of Biology in an active way: a case study, Journal of Biological Education, DOI:
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Unravelling the Central Dogma of Biology in an active way: a case
Lucas Fagundes Silveira , Christian Santos Xavier, Maíra Alexandre Perez ,
Dandie Antunes Bozza , Lupe Furtado-Alle , Iris Hass and Luciane Viater Tureck
Scientific Education Laboratory, Department of Genetics, Federal University of Paraná, Curitiba Paraná State, Brazil
In this paper, we describe a dynamic-model as a strategy to teach DNA
transcription and translation in an active way. This activity aims to provide
learning beyond memorisation through the simulation of molecular pro­
cesses, stimulating the elaboration of questions and hypotheses by stu­
dents. The dynamic consists of four steps, starting with different problem
situations which provide a context and encouragement to start the activ­
ity. The next steps connect these problems with DNA transcription and
translation, requiring the active participation of students to simulate these
processes through a construction of a model based on an iron board and
representations of cellular structures, enzymes and genetic sequences
fixed in magnets. An implementation experience of this dynamic, applied
to 21 undergraduate veterinary students at a public university in the city
of Curitiba, Paraná State, Brazil, is also described. Data from pre and postquestionnaires suggest knowledge about DNA transcription and transla­
tion was improved and some previous mistakes were clarified. Among the
positive aspects that were cited by the students, the words visualisation
and playful were more frequent, which reflect the didactic aspects of the
dynamic. Some points of attention are discussed throughout the paper, as
well as educational implications associated with the material and its
potential to promote active learning.
Genetics; DNA transcription;
DNA translation; active
learning; model; dynamic
DNA structure and processes associated with its functions, such as replication, transcription and
translation are studied at a molecular level in high school and undergraduate courses in biological
and health areas. Nowadays, there are many biotechnological processes and products directly or
indirectly associated with molecular aspects of DNA in sectors such as: medicine, veterinary
medicine, agriculture and industry.
Despite molecular genetics being present in our lives, teaching and learning are still challenging.
Studies have shown consistent results that indicate an interesting phenomenon: in general, students
have some knowledge of concepts in molecular genetics, such as gene and DNA, for example.
However, they are unable to connect these concepts to more complex biological mechanisms, such
as the determination of phenotypic characteristics (Marbach-Ad and Stavy 2000; Lewis and
Kattman 2004; Duncan and Reiser 2007). Some factors contribute to this situation, such as the
complex nature of the subject, specific terminologies and abstract concepts (Duncan and Reiser
2007), and the focus on memorisation of terms and processes (Verhoeff, Waarlo, and Boersma
CONTACT Luciane Viater Tureck
[email protected]
Supplemental data for this article can be accessed here.
© 2021 Royal Society of Biology
2008). Thus, strategies that somehow materialise abstract processes and concepts may be helpful for
students and teachers. In this sense, there are many images, animations and videos available that are
frequently used by teachers to support the learning process (Rutten, van Joolingen, and van der
Veen 2012). However, even using these strategies, students continue to have difficulties, and this
may be due to their passive role during the learning process.
In fact, learning something is an active process, even if it does not involve a practice, because
internally we are in an active cognitive process to internalise and accommodate a new knowledge.
It is possible to achieve this level of success with an expository class; however, some methodol­
ogies can offer a path that requires an active role from students, which naturally favours this
process. In this sense, active learning can be defined as ‘ . . . instructional activities involving
students in doing things and thinking about what they are doing . . . ’ (Bonwell and Eison 1991).
Following this approach, students have the opportunity to formulate questions before teachers
provide answers, thus, overcoming the memorising process. This is also a natural path to
learning, especially in the science field. Strategies that encourage the linking of ideas through
questioning allow the incorporation of the scientific method in didactic activities or practices,
which develops the student’s ability to elaborate and evaluate questions answerable by science.
This is one of the three competencies used by PISA for Development (PISA-D) to measure
scientific literacy, together with the capacity to explain a phenomenon scientifically and interpret
data and evidence scientifically (OECD. PISA OECD 2017), which are also mobilised in this kind
of strategy.
In view of the above, in this paper we describe a dynamic-model strategy to teach DNA
transcription and translation through an active way, starting with problem situations that encou­
rage the questioning and the construction of a didactic model. An implementation experience for
undergraduate veterinary students is also described, which was important in revealing weaknesses
and strengths of the strategy in terms of being in fact an active strategy that stimulates the
formulation of questions.
In the following sections, the design of the dynamic-model strategy is detailed and the imple­
mentation experience is discussed, focused on the aims of the material and its potentiality, as well as
the changes of students’ knowledge about DNA transcription and translation. We conclude with
some educational implications related to the use of this material.
‘Unraveling the Central Dogma of Biology’: an active way to learn
The dynamic-model: ‘Unraveling the Central Dogma of Biology’ was designed to bring contextua­
lisation to abstract processes and to provide an active role to students in the learning process of this
content. The fundamentals of this dynamic-model fit the educational goals of active learning
(Bonwell and Eison 1991), thus, the following description have to be understood as an active
practice, besides the didactic model itself. In summary, the dynamic covers the DNA transcription
and translation processes in eukaryotic cells, from cell signalling to protein secretion, under
a genetic perspective.
The whole dynamic can be divided into four steps: introduction to the problems, general
mechanism, detailed mechanism and sharing/conclusion. The construction of a model is the central
part of the dynamic. The model itself is based on construction of structures and simulation of
processes using magnets and an iron board. The board works as the environment, both intracellular
and extracellular, and the magnets are fixed in representations of cellular structures, enzymes and
genetic sequences in order to allow the reorganisation of the pieces along the iron board according
to the processes’ steps, always prioritising questioning among the students.
In order to control the students’ progress during the dynamic, a script was developed
(Supplementary Material) containing key questions for each step which have to be answered by
the students before they reach the next step. It is an important tool for teachers to ensure that the
fundamental concepts are being worked on.
As every model has its simplifications, once it is difficult to deal with all the details, especially in
molecular genetics, some simplifications of our material have to be considered during its applica­
tion. One important simplification is the transposition of three-dimensional processes and struc­
tures, such as DNA and cell for itself, to a bi-dimensional model. The tutor or professor has to pay
attention to that, in order to avoid misunderstanding of the model. The scale is also a simplification,
considering it is unpractical to build models of cellular processes with real proportions. In our case,
proteins, DNA and RNA are bigger than cell and nucleus. Some proteins were considered together
to avoid an overflow of names; for example, all the proteins contained in the spliceosome were
simplified as a great complex. The timeline of the events is a point of attention too, since the model
aims to elucidate complex processes, each step is explained at a time. However, in the inner cell
environment, these processes might occur simultaneously. A real example: at the start of the preRNA transcription, a five-prime cap is added in the 5ʹ extremity, at the 3ʹ end happens the addition
of the poli(a) tail, and the splicing happens along the whole transcription process. In our model,
each of these events occurs at a different time.
The dynamic-model was developed by four graduated students, under the guidance of professors
of the Science Education Lab of the Genetics Graduate Programme at Federal University of Paraná
(UFPR), located in the city of Curitiba, Southern Brazil, and applied on the same university in two
classes of Veterinary Medicine’s newcomers, in March 2020. The contents approached in this work
are far known by professors, along the years, as common points of mistakes for students. The
difficulties presented by students have led us to create a different way to teach those contents.
The dynamic steps
Step 1: Into a real problem
In order to capture students’ attention and improve their commitment, five different
problems were developed, containing a narrative of a hypothetical situation that students
could face in their future as veterinarians. To solve the problems, students have to finish
the dynamic, because during the building of the model the concepts to answer the
problems are introduced. The five problems can be found in the Supplementary Material
and their basic information is presented in (Table 1)
Each problem is based on a real gene which is associated to an important phenotype in
animals. However, some undesirable traits appear and the veterinarians are asked to solve
the mystery and give a complete biological explanation understandable to a lay person. To
find out what is happening, students have to follow the path of central dogma of biology:
from gene to protein. Each problem has a different cause to the phenotypic variation; thus,
it is necessary to finalise the dynamic and know all the processes to find a solution for the
The professor can choose to work with the five problems at the same time, one per group of
students, or work just one problem with all class students.
Thus, in this step, each group has to read the problem, which is important, once the students
need to understand all the terms used in the text to fully understand the problem. The possible
knowledge gaps may be used to stimulate the active environment. Students should discuss among
themselves to share knowledge and try to create hypotheses to answer the problems. They will,
eventually, ask for help, and then the professor should act as a tutor, leading to the right path
without telling them directly.
The materials delivered to students in this step are: the script and one copy of the problem
(Supplementary Material).
When the problem is fully understood, the class or group can reach the general mechanism step.
Table 1. Summary of the problems used in the dynamic.
Problem title
‘What does he have that
I don’t have?’
‘Very exciting
vacations . . . .in the
farm fish’
‘The Mini Mammary
Glands Mystery’
‘A sweet dog!’
‘Stay healthy . . . If you
Vitellogenin Eggs that don’t
Adenine to guanine transition at the 6th pair-base
Deletion of the 4th pair-base at the 5th exon
Adenine to thymine transversion at the last base of the 3th exon
udder and teats.
Thymine to guanine transversion at the 12th pair-base –
Adenine to thymine transversion at the 14th pair-base
Get sick with new Thymine to adenine transversion at the 6th pair-base of the 4th
exon. Change in the splicing site.
Note: Each problem has its own text available in the Supplementary Material.
Step 2: The general mechanism
The general mechanism step consists of a simplification of the signalling-expression pathway and its
function is to bring the problem to a molecular level.
In this moment, the professor presents to students the iron board and a ‘general mechanism kit’
for each group. Based on the elements available in the kit, the students have to represent the
extracellular, cytosol and intranuclear environments, explaining how a gene can be expressed,
starting with a signalling molecule (Figure 1).
Figure 1. The general mechanism step representing the signalling-expression pathway and the extracellular, cytosol and
intranuclear environments bounded by cellular and nuclear membranes.
The kit elements have generic names for the structures, as an example: signal molecule and
protein, and the students have to name those structures properly, using the terms that appeared in
the problem. At this moment, the professor role is to manage the learning process, preventing the
detachment of the theme and asking guiding questions to lead the students. At the end, the students
should be able to perceive the relationship between an extracellular stimulus and the transcription
of a gene, placing the process in a cellular and physiological context. It is common to learn about
DNA replication before DNA transcription and translation, and some students may confuse these
processes by thinking that before a gene is transcribed it must be replicated. Thus, this step also
works as a way to differentiate these processes from replication of DNA, regarding the moment in
the cell cycle, stimulus and structures involved.
The materials delivered to students in this step are: an iron board (1 m x 1 m) and the general
mechanism kit containing: lipoprotein membranes (cellular and nuclear), extracellular signal,
membrane receptor, mediator 1 and 2, transcription factor, DNA molecule, RNA molecule, RNA
polymerase, ribosome and a protein. All these elements are schematic and can be printed and then
pasted on a magnetic surface or magnets (Supplementary Material).
Step 3: The detailed mechanism
The detailed mechanism comes right after the general mechanism step and deals with transcription
(Figure 2) and translation (Figure 3) from gene sequences to polypeptides.
In the detailed mechanism step, the same iron board is used, however, another kit should be
made available to students. The ‘detailed mechanism kit’ for each group contains: two DNA
molecules (representing two gene sequences – referring to the phenotypes described in the
problems), two RNA strands to fill, two RNA polymerase, two transcription factors; two cap 5ʹ,
two spliceosome complex, two SR protein (serine and arginine-rich protein), two U1 and U2
ribonucleoproteins (small nuclear ribonucleoproteins); two poly A tail, two aminoacyl-tRNA
synthetase (Supplementary Material) and a genetic code; beyond tRNAs, two ribosomes, 2 pieces
Figure 2. The detailed mechanism step representing the DNA transcription from gene sequences. a: The DNA transcription
process. The 3ʹ-5ʹ strand is the template strand and the 5ʹ-3ʹ strand is the coding strand. b: The RNA molecule and the splicing
process. c: The mature RNA molecule.
Figure 3. The DNA translation process. a: Ribosome structure. b: Protein formation. c: tRNA in details.
of 30 cm length wire and amino acids, that the professor must prepare according to the instructions
also available in Supplementary Material.
The goal of this step is to make the transcription and translation processes as clear as possible
through an active way. To achieve this, the students should start from fictitious genic sequences.
At the first moment, the students will need to identify all the elements presented. To make this
moment as beneficial as possible, the tutor has to ask about all structures, including all the regions of
the gene (enhancer, 5ʹ untranslated region, promoter, exon, intron, 3ʹ untranslated region). Other
questions can be done too, like questions related to what moment each element acts in each process.
When the students got familiar with the material, the detailed mechanism practice can be started.
Initially, the transcription should be simulated, for this, the students have to work with the DNA
strands. For each gene copy, there are two sequences: a 5ʹ-3ʹ DNA strand and a 3ʹ-5ʹ DNA strand.
The 3ʹ-5ʹ DNA strands are already filled and the students should fill the 5ʹ-3ʹ DNA strands with the
complementary bases (Figure 2a). Always keeping caution to not confuse them with the replication
process. To simplify, only one gene copy from an animal (always homozygous) is represented: one
DNA molecule (two strands). Remembering, we have two animals in each problem: one represents
the ‘common’ phenotype, and other animal represents the variation of this phenotype, carrier of
undesirable trait, thus two DNA molecules are represented in the dynamic.
Five well-known genes are used in the problems and their characteristics are described as
follows: the mutated insulin gene has two transversions at the beginning of the promoter region,
causing a reduction in transcription rate in the mutated animal. The mutated leptin gene also has
two transversions, however, in the first enhancer, resulting in a reduction in transcription rate too.
The vitellogenin mutated gene has a deletion in the last exon that changes the reading frame,
changing the terminal sequence of the protein and forming a premature stop codon. The prolactin
mutated gene has a transversion in the last base of the third exon, adding a stop codon and
shrinking the final protein in two exons. The mutated regenerating islet-derived 3 gamma gene
(REG3G) gene has a transversion on the fourth exon, which modify the branch site, resulting in the
removal of this exon during the splicing (Table 1).
After filling the DNA strands, the students should discuss what elements act in the transcription
process, which is the resulting molecule, which DNA strand is used as a mould and why RNA
polymerase follows the 5ʹ-3ʹ directionality. Students should act as RNA polymerases and make the
DNA transcription, writing the right RNA sequence from the 3ʹ-5ʹ DNA strand (Figure 2a).
The 5ʹcap must be added at the beginning of the preRNA formation and the addition of the
poli(a) tail at the 3ʹ end. All these processes occurred in the nuclear region of the iron board. After
that, the splicing process is performed on the preRNA molecule, always representing the process
through the elements available in the kit (Figure 2b). The RNA strands should be cut between
introns and exons, forming shorter RNA strands (Figure 2c).
A theoretical pause is recommended at this point. The practice can be stopped and the professor
can review the main points and check if all the students are keeping up with the pace of learning the
processes being taught so far.
Ending the pause, the translation process can be started. It starts exactly at the point the students
stopped: with de mature mRNA leaving the nucleus.
With the help of a genetic code table, the students must build some tRNAs with correct
anticodons and amino acids (Figure 3c), and build the proteins using the ribosome model. The
ribosome model was made with a half styrofoam ball with 10 cm of diameter cut in two parts and
with a squared hole at the centre, to show the two subunits and the sites for the tRNA (Figure 3a).
The proteins are constructed by the students using tiny balls of styrofoam spiked in a piece of wire
(Figure 3b).
At the end of this practical part, all groups will have two proteins: one normal and one mutant
from each DNA molecule, and they can return to the problem situation to elaborate a collective
answer. It is also important to check the script with the key questions in each step.
Then, the professor makes another theoretical pause to review the main points of the translation
process and check the students doubts. In the (Figure 4) it is possible to see all the elements in the
iron board.
Step 4: Answering the problem and sharing the experience
This step is important since the groups work with different problems and sharing these different
problems with different solutions may bring a whole view of these contents. They do not need
necessarily to prepare a formal presentation, just need to talk about and explain the problem and
what was the cause of the phenotype variation.
Implementation and knowledge assessment
In this section are described an implementation experience of the ‘Unravelling the Central Dogma
of Biology’ dynamic and changes in students’ knowledge regarding molecular genetics.
The dynamic was designed to cover the DNA transcription and translation topics focusing firstyear students of the veterinary medicine course at a public university in Southern Brazil. However,
the dynamic is perfectly adaptable to be applied in other courses, only changing the problems
Figure 4. The iron board with all the elements.
The implementation experience included twenty-one students (divided into two groups),
mean age of 20 years. In the Supplementary Material it is possible to see a picture of the
implementation experience with some students. In each group, five hours were spent with the
dynamic. Firstly, a questionnaire was applied to students (PreQ) to investigate how much they
knew about DNA transcription and translation and whether they expected to have difficulties
with these topics. After the dynamic, other questionnaire was applied (PosQ), containing the
same questions with the addition of two open questions asking the students’ opinion about the
In each class the students worked in smaller groups containing 4 to 5 students. Each group
received: a problem situation that guided the activity, a script with check questions to be followed by
the group and supervised by a tutor, a general mechanism kit and a detailed mechanism kit to build
the model. Each group was coordinated by the tutor (postgraduate student) and the professor
responsible for the class acted as a general tutor, controlling the time, helping on the more complex
mediations and executing the theory pauses.
The steps that composed the implementation experience are summarised in the (Figure 5)
Figure 5. Sequence of steps during the implementation process. Note: PreQ: Pre-questionnaire; PR: Problem Reading; GM:
General Mecanism step; DM: Detailed Mechanism step divided in: TSC: Transcription; S: Splicing; TP1: First theoretical pause; TRA:
Translation; TP2: Second theoretical pause; C: Conclusion; PostQ: Post-questionnaire.
Implementation of the dynamic
The most important points regarding the implementation experience are described below.
The dynamic was applied to four groups at the same time, and the first step was the reading of
the problem situation. The problem situations were fundamental to connect the theoretical con­
cepts and real situations that will eventually be present in the work of a veterinarian. We could
observe the reactions among the students: their surprise, insights, doubts, hypothesis formation,
discussions and argumentations towards finding an answer to the problem presented; all these
reactions created an active learning environment. Moreover, the problem represented a common
point, which drove the whole dynamic.
The second step consisted of working in a general perspective, connecting elements of the
problem with cellular and molecular structures. In this step, the students received the general
mechanism kit and the aim was to find the correct position of the elements in an intracellular and
extracellular environment (Figure 1), and to explain the connection of this generic elements (such
as signalling molecule) with the problem. We observed that this step allowed us to identify some
cellular biology misconceptions and, mainly, this step facilitated the contextualisation of transcrip­
tion and translation as processes which respond to a cellular or/and environmental demand, unlike
DNA replication, which occurs in a different phase of cellular cycle. In fact, we have observed that
some of our students frequently understand DNA replication as a first process, necessary to
continue to transcription and translation of DNA. We can hypothesise that the sequence in
which these topics are usually taught have contributed to this situation.
The third step aimed to bring the students into a molecular world. In this step, each group
received the detailed mechanism kit and they had to build a new mRNA molecule (Figure 2) and the
correspondent protein (Figure 3), doing all the processes and understanding concepts, such as:
coding and template strand, 3ʹ-5ʹ ends, promoter region, enhancers, homozygous and heterozy­
gous, genetic code, among others. During the process, it was possible to identify the causes for the
unwanted phenotypes described in the problems, providing the necessary biological basis to explain
these problems.
Before starting the transcription process, the students completed the coding strand of DNA to
deal with the base pairing. Nevertheless, we realised that some students had understood that a new
DNA strand is built before the transcription process, as we highlighted before. A possible solution
to avoid this mistake is work with both strands filled in, or clarify the purpose of this activity. After
that, the students did the transcription of the two ‘genic sequences’ in each group. For that, they had
to discuss some questions, such as: how is a gene recognised? Where does the transcription start?
Who does the RNA polymerisation? The kit parts were handled at the same time, which provided
an active and dynamic experience.
The splicing process was also discussed. We found some difficulties to adapt this complex
process to our material, however, we observed that some important concepts were better under­
stood, as exon, intron and spliceosome.
After the last activity described above, the first theoretical pause was conducted. The dynamic
may contain this step or not, it can be a choice of the professor. In our context, this step was
important to verify the remaining doubts and to put all groups in the same level of understanding.
We do not advise long theoretical hours with excess of content in this step, because it can take the
focus off the activity and discourage students.
The last process we worked on was the translation. The material handling allowed
a tridimensional experience to know about the protein synthesis and its steps: coupling of the
initiation complex, pairing between codon and anticodon, tRNA positioning at ribosome sites, and
protein formation. The sequence of events and how the process evolves to build a protein were
discussed by the students with the guidance of the tutor. The students tried to simulate the process
with the elements available in the kit, and often they noticed inconsistencies in their thinking
processes, these situations stimulated the discussion and the trial and error learning.
It is important to mention that the script with check questions was essential to ensure that all
groups had seen the same points and to situate the students regarding the learning aims. With this
material, they knew when and what they had to learn.
After a second theoretical pause, we finished the class and in the subsequent class we conducted
a brief conclusion moment. Each group read and answered the problem, sharing the experience
with colleagues.
Knowledge assessment
Students answered four general questions about the central dogma, transcription and translation of
the DNA and the protein diversity before starting the dynamic and after the conclusion (last step of
the dynamic). Their answers were analysed in two ways: counting the right and wrong answers
across the whole group in the pre-questionnaire (PreQ) and post-questionnaire (PostQ) (Figure 6),
Figure 6. Evaluation of the answers to each question in the pre and post-questionnaires. Note: Q1: Question 1- Description of the
Central Dogma; Q2: Question 2 – Definition of the transcription process; Q3: Question 3 – Definition of the translation process; Q4:
Question 4 – Description of the processes responsible for protein variability. PreQ: pre-questionnaire; PostQ: post-questionnaire.
Changes in the percentage of correct and wrong answers, comparing pre and post questionnaires, were not statistically
significant in any question (p > 0.05).
Figure 7. Changes in students’ answers to each question in the pre and post-questionnaires. Note: Blank answers were not
included in these analyzes. In ‘wrong group’ are included students who answered correctly with minor or serious conceptual
mistake. Q1: Question 1- Description of the Central Dogma; Q2: Question 2 – Definition of the transcription process; Q3: Question
3 – Definition of the translation process; Q4: Question 4 – Description of the processes responsible for protein variability. PreQ:
pre-questionnaire; PostQ: post-questionnaire; Conclusion: results from post-questionnaire.
and also in a paired way, considering the changes in the students’ answers from the PreQ to the
PostQ (Figure 7).
Firstly, they were requested to describe the way from DNA to protein (Q1). Initially, 71% of the
answers were totally correct and this percentage increased by 10% after the dynamic (Figure 6).
Approximately 33% of the students who provided a wrong answer remained with erroneous
conceptions about the central dogma (Figure 7). Then, the students were asked to describe the
transcription process (Q2). Before the dynamic, 43% of the students properly described the process,
this percentage increased to 57% after the dynamic (Figure 6). Considering those who initially
answered in a wrong way (PreQ), 45.5% of them changed to a correct answer in the PostQ (Figure
7). In the next question, the students were asked to describe the translation process (Q3). Absolutely
correct definitions increased from 48% to 67% after the dynamic. Approximately 56% of the
students who initially provided wrong definitions changed to right definitions after the dynamic
(Figure 7).
Regarding the fourth question (Q4), it was possible to verify that the students had no initial
knowledge about the mechanisms responsible by protein variety, since nobody provided totally
correct answers (Figure 6). Even after the dynamic, only 10% provided totally correct answers
(Figure 7). We had expected answers including alternative splicing and its consequences for the
protein variety. Perhaps, the students had focussed on the complexity of the splicing process and did
not think about the next step, that is, the consequence of the splicing – protein variability. It can be
due to the practice itself, or the stimulus provided by the professor and tutors were not sufficient to
clarify this point.
In a general way, it was possible to associate the dynamic with improved knowledge of DNA
transcription and translation; however, the increase in the correct answers proportion in the postquestionnaire was not significant. Some factors can be associated to this result. Transcription and
translation of DNA are difficult contents, and it is possible that the students may need other
strategies besides the dynamic to learn. For most of these students, this was the first experience with
an active teaching strategy and because it is new, their teaching potential may not have been
explored properly by the students and even the tutors.
Other possibility is that the importance of the questionnaires for the students was not clear and
they did not answer so seriously. The short time they spent responding the questionnaires suggests
a lack of commitment with this task.
Regarding these results, there is other important observation to discuss. As seen in the (Figure 7),
a small percentage of students who had answered correctly in the pre-questionnaire, answered the
same question incorrectly in the post-questionnaire. This pattern was observed in the first three
questions. We investigated the possible causes for this situation, and we noticed that these students
had answered the pre-questionnaire in a succinct way, but, in the post-questionnaire, they answered
the same question in a more elaborate way, with more details and with minor conceptual mistake.
Thus, all these students that answered initially in a totally correct way, answered the same question
correctly with a minor conceptual mistake after the dynamic. Possibly, more information was added
to the initial knowledge of these students, however, there was not enough time and/or stimulus to
connect this information and to develop a more complex answer totally correct.
It would be interesting to compare these results with another independent experience (a
traditional class experience, for example), in order to evaluate the efficacy of the dynamic compared
to other methodologies.
Finally, regarding the last question of the PreQ, 38% of the students expected to have difficulties
with these contents, 19% expected to have a bit of difficult, while 43% believed they would have no
difficulties. These data might reflect the academic heterogeneity of these students, since approxi­
mately half of them expected to have difficulties, while the other half did not expect it. Actually, in
this group, we had some repeating students, students coming from private schools and from public
schools. Unfortunately, in Brazil, there are a huge discrepancy between private and public schools,
and this situation contributes to the basic formation of the students.
In the PostQ, there were two additional questions. In the first question, students described
concepts that became clear or less confusing after the dynamic, if there were previously misunder­
stood or unclear concepts about the contents. The second one asked for positive and negative
Figure 8. Word cloud generated from the students’ answers to the open questions of the post-questionnaire. Note: The cloud on
the left refers to the concepts clarified after the dynamic according to the students. The cloud on the right refers to the positive
aspects of the dynamic according to the students.
aspects of the dynamic. We opted to show these results through a word cloud, in which words that
appeared the most are in larger size, how it is possible see in the (Figure 8)
Among the concepts clarified by the dynamic, splicing was the most mentioned. It can be due to
the lack of explanation during the high school, despite the term appearing in textbooks. Basically,
we did not have negative aspects mentioned by the students, and among the positive aspects, the
words visualisation and playful were frequently mentioned. This reflects the purpose of the
dynamic: learning these contents less abstractly and more actively.
Educational implications
Educational researches have sought to find teaching strategies that promote learning beyond
memorisation. In this sense, active strategies have didactic aspects that can provide ways to achieve
a more lasting learning, able to articulate with other knowledges. Molecular genetics is widely seen
as a content that needs to be memorised to be learned. Our proposal is to make available to other
professors and teachers a didactic strategy which brings some assumptions of active learning,
without however, fitting into a well-known model of active learning. We developed this dynamic
with a focus on undergraduate veterinary students and the skills derived from the contents of
molecular genetics are of great importance for these students, since molecular approaches, such as
recombinant DNA technology and molecular diagnostics, are, nowadays, common in clinical
practice and also in research and development. Although the focus of the material was on the
future veterinarian, it is easily adaptable to other courses, considering that the contents of molecular
genetics are taught in many other graduate courses.
The authors would like to thank the veterinary medicine students for their enthusiastic participation.
Disclosure statement
No potential conflict of interest was reported by the authors.
This work had no financial support.
Lucas Fagundes Silveira
Maíra Alexandre Perez
Dandie Antunes Bozza
Lupe Furtado-Alle
Iris Hass
Luciane Viater Tureck
Bonwell, C. C. J., and J. A. Eison 1991. “Active Learning: Creating Excitement in the Classroom”. ASHE-ERIC Higher
Education Reports.
Duncan, R. G., and B. J. Reiser. 2007. “Reasoning across Ontologically Distinct Levels: Students’ Understandings of
Molecular Genetics.” Journal of Research in Science Teaching 44 (7): 938–959. doi:10.1002/tea.20186.
Lewis, J., and U. Kattman. 2004. “Traits, Genes, Particles and Information: Re-visiting Students’ Understandings of
Genetics.” International Journal of Science Education 26 (2): 195–206. doi:10.1080/0950069032000072782.
Marbach-Ad, G., and R. Stavy. 2000. “Students’ Cellular and Molecular Explanations of Genetic Phenomena.” Journal
of Biological Education 34 (4): 200. doi:10.1080/00219266.2000.9655718.
OECD (2017), “PISA for Development Assessment and Analytical Framework: Reading, Mathematics and Science.”
Preliminary Version, OECD Publishing. Paris. Accessed 24 April 2020.
Rutten, N., W. R. van Joolingen, and J. T. van der Veen. 2012. “The Learning Effects of Computer Simulations in
Science Education.” Computers & Education 58 (1): 136–153.
Verhoeff, R. P., A. J. Waarlo, and K. T. Boersma. 2008. “Systems Modelling and the Development of Coherent
Understanding of Cell Biology.” International Journal of Science Education 30 (4): 543–568. doi:10.1080/
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