Meroblastic

Definition

Meroblastic refers to a type of incomplete embryonic cleavage where only a portion of the egg divides. This occurs in eggs with a large amount of yolk, such as those of birds and reptiles.

5 Must Know Facts For Your Next Test

1. Meroblastic cleavage results in a blastodisc, which is a cap of cells atop the yolk.
2. In meroblastic cleavage, only the cytoplasmic region undergoes division while the yolk remains undivided.
3. This type of cleavage is common in species with eggs that have high amounts of yolk, like birds and fish.
4. Meroblastic cleavage can be further divided into discoidal and superficial types.
5. In contrast to meroblastic, holoblastic cleavage involves complete division of the egg.

Review Questions

Related terms

Holoblastic: A type of complete embryonic cleavage where the entire egg divides.

Blastodisc: A cap-like structure formed during meroblastic cleavage on top of the yolk.

Yolk: Nutrient-rich material in an egg that provides food for the developing embryo.