Deck 2: Cells

Question 1

Severe childhood autosomal recessive muscular dystrophy, prevalent in North Africa, affects both sexes and is caused by a deficiency of a dystrophin-associated glycoprotein called adhalin. Explain how mutations in two different genes - those for dystrophin and adhalin - can cause the same symptoms of muscle wasting.

Answer 1

The two proteins function together to maintain muscle cell integrity, so when either is abnormal, the result can be muscle weakness.

Question 2

Why wouldn't you expect to see adults with mutations in the telomerase gene that affect phenotype?

Answer 2

An individual without telomerase would never develop specialized tissue, and would not survive very far into prenatal development.

Question 3

A mouse has the gene encoding a particular enzyme inactivated or "knocked out" and is a model of the human genetic disease Zellweger syndrome. Which organelle do cells of these mice lack?

Answer 3

Peroxisomes

Question 4

Achondroplasia is the most common form of inherited dwarfism. The causative gene encodes a protein receptor on surfaces of bone and cartilage cells that normally binds a growth factor. Explain how an abnormal form of this gene might cause dwarfism.

Question 5

In the novel The Cobra Event , by Richard Preston, a genetically engineered deadly virus is used as a weapon. The virus inserts into the human genome and disrupts production of an enzyme, causing an inborn error of metabolism leading to self mutilation by uncontrollable biting of the lips, fingers, and shoulders. Which genetic disease mentioned in the chapter does this sound like?

Question 6

Match the disorder to the organelle, biochemical, or structure that is abnormal.

Question 7

How does Duchenne Muscular Dystrophy (DMD) demonstrate that the cytoskeleton, cell membrane, and extracellular matrix interact?

Question 8

Describe a disorder caused by: a. faulty cell adhesion
B) a deficient lysosomal enzyme
C) an abnormal or missing peroxisomal protein
D) a cytoskeletal abnormality