Topic 4: Gamete Formation - Fertilization

Question 1

What occurs in fertilization?

Answer 1

• spermatozoon (n) contacts and penetrates oocyte (n)

Question 2

Why is the egg arrested in meiosis II?

Answer 2

• is arrested until penetrated by sperm

Question 3

What does fertilization trigger? (4)

Answer 3

• the completion of meiosis II in 2° oocyte
• forms ovum (egg)
  then ♂ + ♀ pronuclei unite
• new cell is a zygote

Question 4

What is the pronucleus?

Answer 4

• nucleus of sperm/egg post-fertilization but prior to fusion