CASE STUDY #1

1. Amy is cooking dinner for her family. She moves to pull a pot off the stove and accidently touches the burner. She reflexively pulls her finger away from the stove and immediately feels the pain.
   1. Which receptor neuron is responsible for sending information from her finger to her peripheral nervous system?
   2. Is this receptor neuron, an afferent or efferent neuron?
   3. Explain where the information from the receptor neuron is sent and how does it result in Amy moving her finger away from the stove.
   4. Describe the three classes of neurons involved in this response.
   5. Evolutionarily, why do you think the human body has this system in place?
   6. What might happen if we did not have this response?

CASE STUDY #2

1. Glen, who is 45 years old, begins to notice that his hands shake (tremors) when he is performing everyday tasks such as signing his signature. His family members have noticed that he also has muffled speech and tends to shuffle when he walks. He is diagnosed with Early Onset Parkinson’s disease.
   1. What is Early Onset Parkinson’s disease?
   2. What specific cell type is affected in Parkinson’s disease?
   3. What is dopamine? What effects does dopamine have on the body?
   4. Explain the structure of a synapse and why Glen’s neurologist would prescribe him a dopamine agonist?
   5. Glen has genetic testing performed and it is determined that he does carry an autosomal dominant mutation in the SNCA gene associated with Early Onset Parkinson’s disease. Glen has three children. Would you advise his children to have genetic testing performed to determine if they also carry the disease mutation? Why or why not?

CASE STUDY #3

3. Patricia, who is 37 years old, discusses with her physician recent symptoms that she has experienced including blurred vision, numbness in her fingers and face, dizziness, fatigue and weakness. The physician performs multiple neurological tests and she is diagnosed with multiple sclerosis (MS).

1. What is MS?
2. Is MS a disease of the central or peripheral nervous system?
3. What is the main cell structure affected in MS?
4. How is the action potential of a neuron affected in MS?
5. The origins of MS are not clear. What do scientists hypothesize to be the causes of MS

Part I: Answer the following questions:

1. Which of the following is most inclusive?

a. allele

b. genotype

2. Dominant alleles are represented by:

a. an upper case letter

b. a lower case letter

c. it does not matter what type of letter is used

3. In fruit flies, gray body color is dominant over black body color. Using the letter G to represent body color, what is the genotype of a heterozygous gray bodied fly?

a. GG

b. gg

c. Gg

d. GGgg

4. All of the offspring of two gray bodied flys are also gray. What can you conclude about the genotypes of the parent flies?

a. They are both heterozygous

b. They are both homozygous dominant

c. They are both homozygous recessive

d. You cannot conclude anything definitively about the parental genotypes

5. Some of the offspring of two gray bodied flies are black. What can you conclude about the genotypes of the parent flies?

a. They are both heterozygous

b. They are both homozygous dominant

c. They are both homozygous recessive

d. You cannot conclude anything definitively about the parental genotypes

Part II: Follow the instructions in the Question column to complete the virtual lab scenarios and record your data:

Complete all ten scenarios and record your results in Table 1.

When you record a ratio, whether it is genotypic or phenotypic ratio, always record the most dominant characteristic first, followed by the recessive.  For example, when recording genotypic ratios:     1)  If your offspring genotypes include 1 GG, 2 Gg, and 1 gg, the ratio would be:      1 GG : 2 Gg : 1 gg     2)  If your offspring genotypes include 2 GG and 2 Gg, the ratio would be:                2 GG : 2 gg   (or 1:1 in the reduced form)     3)  If your offspring genotypes are 4 gg, then the ratio would be written as::               4 gg

When you record phenotypic ratios for a monohybrid cross, there are only two possible phenotypes – either the dominant phenotype or the recessive phenotype.  So you do not need to indicate the phenotype, simply put the dominant # first, followed by the recessive #:     4)  If your offspring phenotypes are 3 dominant and 1 recessive, the ratio is:               3:1     5)  If your offspring phenotypes are 4 dominant and 0 recessive, the ratio is:               4:0     6)  If your offspring phenotypes are 0 dominant and 4 recessive, the ratio is:               0:4

Table 1:

Scenario #	Genotype of Parent I	Genotype of  Parent II	Genotypic Ratio of Offspring	Phenotypic Ratio of Offspring
1
2
3
4
5
6
7
8
9
10