Invagination in the Sea Urchin Blastula

question 75

Multiple Choice

Invagination in the sea urchin blastula

• A) forms the neural tube.
• B) involves contractile filopodia extending from the endoderm cells.
• C) creates a blastopore that becomes the mouth.
• D) forms the archenteron.
• E) occurs just prior to the blastula stage.

---

Definitions:

Breakeven Point

When the expenses and the revenue are equal, so that there is no profit or loss.

Expense Function

A mathematical expression that describes how costs change with variations in the volume of activity.

Expense Functions

Mathematical formulas used to describe the relationship between expenses and other variables such as production or sales volume.

Revenue Functions

Mathematical functions that represent the revenue generated by selling products or services as a function of their price or quantity.