Biology Scholars Exam Questions that align with learning objectives
Learning Objective:
Students will be able to design an experiment that uses targeting in mice to understand
the effects of mutation of genes involved in FGFR3 signaling pathway on the growth of
long bones
1. (3 pts) List two difference between a knockout and a knock-in. Understanding
2. (5 pts) You are generating a knock-in mutation in exon 5 in the gene below. In the
drawing, indicate the relative positions of the following elements of the targeting
vector you will need to generate this knock-in (select all that apply, not all elements
might be used): neo*, Regions of Homology 1 and 2 (RH1 and RH2), loxP, tk. (*neo
marker does not have to be conditionally deleted) Application
A to C
mutation
here
4
5
6
3. What type of mouse would BEST model for Achondroplasia? Understanding
A. A mouse homozygous for the knock-out of FGFR3
B. A mouse with a conditional knock-out of FGFR3 gene in the chondrocytes
C. A mouse transgenic for a hyper-active FGFR3
D. A mouse homozygous for the knock-in allele that produces hyper-active FGFR3 in
the liver
4. You have joined a lab that investigates the molecular mechanisms of a rare inherited
human disorder that results in abnormally elongated limbs. Upon sequencing the FGFR3
receptor in the normal and affected individuals, you discover a SNP that is is resent in the
affected but not in the normal individuals. The SNP is located in the kinase domain of
this receptor.
Biology Scholars Exam Questions that align with learning objectives
i. Based on what you know about the role of FGFR3 in regulation of the growth of the
long bones, what change in the FGFR3 protein activity do you predict this mutation will
cause? Application
A. increased kinase activity, decreased Ras activation
B. increased kinase activity, increased Ras activation
C. decreased kinase activity, decreased Ras activation
D. decreased kinase activity, decreased Ras activation
ii. Design an experiment that would test whether the FGFR3-associated SNP observed in
the affected individuals causes elongation of the bones in mice.
A. Formulate your hypothesis:
B. Describe the genotypes
- of the experimental mice
- of the control mice
C. How would you measure the results of your experiment? Which cells will you be
looking at and how will you specifically identify those cells?
D. What result would refute your hypothesis?
5. You are studying a recessive disorder that causes dwarfism in humans. You have
discovered a gene coding for a growth factor that appears to be present in a severely
decrease amounts in the chondrocytes of the affected individuals relatively to normal
individuals. You hypothesize that the decreased dose of this gene’s product has an
important role in the decreased bone growth. Design an experiment that would test this
hypothesis.
Learning Objective:
Students will be able to interpret experimental data from primary research articles,
specifically:
- Identify the overall goal of the paper, the "big" question it wanted to answer
-Identify the specific experimental question asked in selected figures from the paper.
- Be able to identify the controls and why these controls are being used (what do they
control for?)
Biology Scholars Exam Questions that align with learning objectives
- Be able to describe and interpret the experimental results
- Be able to draw immediate conclusions from the results: did the experiment answer the
question it aimed to answer?
Question 1. Analysis. The figure below is from paper #1 by Wang et al. (1999) “A
mouse model for achondroplasia produced by targeting fibroblast growth factor receptor
3”, discussed in sections last week. The wild type specimen is on the left (panels C and
E) and the mutant specimen is on the right (panels D and F). In panels C and D, the tissue
is stained with hematoxilin-eosin, dyes that help outline the cells and the nuclei (plural of
nucleus) inside the cells. Panels E and F the tissue is stained for the mRNA of collagen
type II. PZ stands for proliferating zone, HZ stands for hypertrophic zone.
i. Which of the following is true in regard to the genotype of the mutant tested in this
figure? (2 pts) Analysis
A. It contains one allele of FGFR3 G374R mutation and no neo gene
B. It contains two alleles of FGFR3 G374R and neo gene
C. It contains one allele FGFR3 G374R, neo, and tk genes
D. It contains a transgene of collagen type II G374R and neomycin gene
ii. In no more than three sentences, describe the results shown in the figure below: what
was the effect of the mutation and what type of cells was affected? (3 pts) Analysis
iii. Based on the results presented in this figure what was the effect of the mutation
examined here (specimen on the right)? (2 pts) Analysis
A. Hyper-activation of the FGFR3 pathway
B. Inhibition of the FGFR3 pathway
C. No effect on the FGFR3 pathway
Biology Scholars Exam Questions that align with learning objectives
Question 2. Synthesis The figure above is from the paper by Wang et al. (1999) “A
mouse model for achondroplasia produced by targeting fibroblast growth factor receptor
3”, discussed in sections last week. The wild type specimen is on the left (panels C and
E) and the mutant specimen is on the right (panels D and F). In panels C and D, the tissue
is stained with hematoxilin-eosin, dyes that help outline the cells and the nuclei (plural of
nucleus) inside the cells. Panels E and F the tissue is stained for the mRNA of collagen
type II. PZ stands for proliferating zone, HZ stands for hypertrophic zone.
You are asked to quantify the data from this experiment and summarize your results in
the form of a graph.
A. What would you measure (more than one correct answer is possible)?
B. Draw the expected results of these measurements from the experimental and
control animals as a bar graph, clearly labeling the axes and the columns.
Biology Scholars Exam Questions that align with learning objectives
C. Size is very important in quantitative experiments, as it captures the variability of
biological responses. To ensure that you are capturing this variability, you will
need to look at several _______ (choose from the options below)
A. Specimens from the bone tissue from the same animal
B. Chondrocyte cells stained with eosin-hematoxylin
C. Experimental and control mice