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Which gait deviation is commonly observed in patients with weak dorsiflexion?

A patient has been diagnosed with a leg length discrepancy and demonstrates a compensatory gait deviation. Which of the following is most likely?

A patient recovering from a stroke exhibits a circumduction gait pattern. What is the most likely cause?

Sox proteins are transcription factors, so one hypothesis to explain the different morphologies of mouse and chick lung would be that Sox9 is activating expression of a gene in chick lung that results in fusion of the bronchial tips.  Imagine you have identified a gene – let’s call it Fuse1 – that you think is the molecule responsible for tip fusion in chick. Design a show it experiment to test your hypothesis that Fuse1 is the molecule responsible for bronchial tip fusion in developing chick lungs.  Describe a result that is consistent with your hypothesis, and one that is inconsistent with your hypothesis 

You are interested in examining anterior-posterior patterning in Tribolium,(flour beetle). You do a mutagenesis screen and identify 4 mutant lines with the phenotypes listed below.  For each, state whether the mutation indicates the gene involved is likely to be in the gap, pair-rule, segment polarity or homeotic class of genes, à la Drosophila.     Note:  Normal Tribolium have head structures, three thoracic segments and 10 abdominal segments. Abdominal segments have hairs in the posterior half of each segment.   Mutant A:  lacks segment A1 and in the normal A1 position there is an extra thoracic segment with legs. Mutant a is Mutant B:  Missing segments T2, T3, A1-A4. Mutant B is Mutant C:  Abdominal segments have hairs across the entire segment. Mutant C is Mutant D:   Missing segments T1, T3, A2, A4, A6, A8, A10. Mutant D is

Sox proteins are transcription factors, so one hypothesis to explain the different morphologies of mouse and chick lung would be that Sox9 is activating expression of a gene in chick lung that results in fusion of the bronchial tips.  Imagine you have identified a gene – let’s call it Fuse1 – that you think is the molecule responsible for tip fusion in chick.   Design a lose it experiment to test your hypothesis that Fuse1 is the molecule responsible for bronchial tip fusion in developing chick lungs.  Describe a result that is consistent with your hypothesis, and one that is inconsistent with your hypothesis.      

Lung development in mice and chickens uses many of the same molecules, but results in structurally and physiologically different structures.  Mouse lungs are tree-like, flexible, inflate and deflate and have two way airflow. Chick lungs are rigid, non-expandable, and have one way airflow, and the bronchial branches fuse together to form continuous tubes. (A and C in the image below).     In box mice and chicks, Sox proteins are used for branching; Sox2 is expressed in the main tubes, and Sox9 at the tips of the branches. But in chicken lungs, the ends of the branches fuse, leading to the different mature structure.  Clearly something has changed during evolution, and they are still trying to figure out how all that works.  But here is another example of evolution “using what it has” but deploying those tools in a different way to lead to the development of a new structure.  What do we call this?

A 2004 study found that women who delivered babies with neural tube defects had produced antibodies specific to the folate receptor protein.  Women who delivered babies without neural tube defects did not have these antibodies.  Provide a molecular explanation for the development of neural tube defects in these babies.  

nanos is a maternal effect gene in Drosophila.  You perform the following cross:   nanos-/nanos-  ♀ (female)       X         nanos-/+ ♂ (male)   What are the genotypes and phenotypes of the resulting embryos? 

even-skipped (eve) is expressed in 7 stripes across the Drosophila embryo.  Stripe 3 and 7 are controlled by a common regulatory module that contains multiple enhancers and silencers.  As shown below, Knirps (Kni) and Hunchback (Hb) are repressors, and Mrl and Zelda are activators of eve stripe 3 and 7.  Mrl and Zelda are expressed throughout the entire embryo; the locations of Hb and Kni are indicated in blue and green respectively on the diagram below.  Which of the mages below represents what would happen to eve stripe 3 and 7 expression in a knirps mutant (loss of function) embryo?  Stripe 2 is shown for reference. i