Which feature characterizes cleavage in birds?
A) Cleavage furrows completely divide the egg.
B) The embryo forms as a blastodisc on top of the yolk mass.
C) Cleavage furrows penetrate the large yolk mass.
D) No blastocoel forms.
E) It is similar to the early cleavage stages of the fruit fly.

Question

Quizplus · Accepted Answer

In birds, the embryo forms as a blastodisc on top of the yolk mass. This type of cleavage is called discoidal cleavage, in which the yolk is not divided but instead acts as a nutrient source.

Which Feature Characterizes Cleavage in Birds