In the fast block to polyspermy, binding of sperm opens up ________ channels, which depolarizes the egg membrane and ________
A) Na+; prevents the entrance of Ca2+
B) Na+; prevents the entrance of any more sperm
C) Ca2+; prevents the entrance of more Na+
D) Na+; prevents the entrance of more Na+
E) Ca2+; prevents the entrance of any more sperm
B
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Why do some animals become "resistant" to their dose of phenobarbital? a. They excrete this drug through the kidneys
b. They cannot biotransform this drug. c. Liver enzymes are induced causing the animal to develop tolerance. d. The half-life of the drug is shortened due to the high level of protein binding.
Fine hair called ________, which is unpigmented or lightly pigmented, is the primary human hair and is found on the upper and lower limbs.
A. terminal B. vellus C. cuticle D. lanugo E. phalanx
All of the following are true of a prickling pain sensation except that they
A) are carried by type A fibers. B) reach the CNS quickly. C) cannot be localized to a small area. D) receive conscious attention. E) often trigger somatic reflexes.
Enzymes catalyze degradation reactions but not synthesis reactions.
Answer the following statement true (T) or false (F)