Asked by Reagan Teston on Apr 28, 2024
Verified
Generally only one sperm fertilizes an egg because
A) sperm compete against one another before entering and only the most fit sperm is able to fertilize the egg.
B) sperm travel such a great distance that no two sperm are likely to arrive at the same time.
C) there is only one passageway available for a sperm to enter the egg.
D) many sperm enter but only one set of chromosomes can fuse with the egg nucleus; the other sperm are absorbed.
E) when the first sperm fuses with the egg membrane, the membrane depolarizes, which blocks the entry of any other sperm.
Membrane Depolarizes
The process by which a cell membrane's voltage becomes less negative, leading to the possible firing of an action potential in neurons.
Sperm
Male gamete having a haploid number of chromosomes and the ability to fertilize an egg, the female gamete.
Egg
Also called an ovum; haploid cell that is usually fertilized by a sperm to form a diploid zygote.
- Understand the significance and process of fertilization, including sperm-egg interaction.
Verified Answer
DJ
Destiny JamesApr 29, 2024
Final Answer :
E
Explanation :
When the first sperm fuses with the egg membrane, the membrane depolarizes, which blocks the entry of any other sperm. This is known as the fast block to polyspermy. After this, the egg goes through a slower block to polyspermy, which involves changes in the egg membrane that prevent additional sperm from entering. Therefore, only one sperm is able to fertilize the egg.
Learning Objectives
- Understand the significance and process of fertilization, including sperm-egg interaction.