The darker extremities characteristic of Siamese cats and Himalayan rabbits are due to a ________
a. mutation increasing the activity of an enzyme required for melanin production
b. heat-sensitive form of an enzyme required for melanin production
c. mutation inactivating the enzyme required for melanin production
d. mutation making melanin production insensitive to temperature variations
b
You might also like to view...
Four of the following are modern apes. Which is not a modern ape?
a. gibbon b. new world monkey c. chimpanzee d. gorilla e. orangutan
Sexual reproduction has many benefits from a genetic standpoint. Can you think of any downside to
sexual reproduction? What will be an ideal response?
Hydrophobic interactions are exhibited with
a. ions. b. nonpolar molecules. c. hydration ions. d. polar molecules. e. none of these.
Which statement about ion channels and voltage-gated ion channels is true?
A) Voltage-gated ion channels are always open. B) Ion channels allow ions to flow against their concentration gradients. C) Voltage-gated ion channels only open when a stimulus is applied. D) Ion channels do not contribute to resting membrane potential.