Biology Forums - Study Force

1. Jackie touched a hot stove with her hand and withdrew it automatically. For her cerebrum to be activated by the same stimulus, an additional nerve pathway must be used. This pathway would branch off the reflex arc at the location labelled

a. 2
b. 1
c. 3
d. 4

HINT: She now becomes aware of touching the hot stove.

i picked 2 which is the sensory neuron

2. Melanin pigments lie under the surface of the skin. Exposure to sunlight increases the production of melanin to protect the skin from UV-rays.

The fact that exposure to sunlight increases melanin production in many humans and produces a tan demonstrates that

a.the environment causes mutations that have no effect on the chance of survival
b.the environment causes mutations that have no effect on the chance of survival
c.the environment causes mutations that increase the chance of survival
d.the expression of some genes is influenced by the environment

HINT: IS this a physical or a chemical influence on DNA molecules?

I picked A even tho A and B is given and written twice, i believe its a physical influence on DNA molecules.

3. In a paternity suit, DNA fingerprinting is a test to assist in determining who is the father. If you identify bands that the mother and child have in common, then any bands remaining in the child's DNA fingerprint must be found in the father's DNA fingerprint. Using the information above, determine who is the father of a child.

i said that mother A and child A have a lot bands in common, so A is the father DNA fingerprinting.



Please correct me if I'm wrong on my answers, and give your opinion on what you think is right if you know the correct answer. Thank you

for the first question  I would say A)2 as well