Question

question 17 (5 points) listen which of the following does not generally occur? a) two sperm fertilizing two different eggs at the same time b) two different sperm both fertilizing the same egg c) a single sperm fertilizing a single egg d) a fertilized egg splitting into two embryos question 18 (5 points) listen the air that we breath is made mostly of which gaseous molecule? a) helium b) nitrogen c) oxygen d) hydrogen

Explanation:

For Question 17, in normal human fertilization, polyspermy (multiple sperm fertilizing one egg) is blocked by the egg's protective layers and biochemical reactions, so two different sperm fertilizing the same egg does not generally occur. Option A results in fraternal twins, option C is normal fertilization, and option D results in identical twins.
For Question 18, air is composed of about 78% nitrogen, 21% oxygen, and small amounts of other gases like argon, carbon - dioxide, etc. So the main gaseous molecule in air is nitrogen.

Answer:

Question 17: B. Two different sperm both fertilizing the same egg
Question 18: B. Nitrogen