What Occurs During Gastrulation

question 74

Multiple Choice

What occurs during gastrulation?

• A) A solid embryo is changed into a hollow morula.
• B) A solid blastula is changed into a hollow embryo that has four tissue layers.
• C) A hollow blastula is changed into a hollow embryo that has three tissue layers.
• D) A neural tube is created by invagination of the ectoderm.

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Definitions:

Menstrual Cycle

The regular natural change that occurs in the female reproductive system that makes pregnancy possible, typically lasting about one month.

Fertile Window

The time in a woman's menstrual cycle during which she has the highest chance of becoming pregnant, typically a few days before and including the day of ovulation.

Days

Units of time equivalent to 24 hours, representing the period it takes for Earth to complete one rotation on its axis.

Monozygotic Twins

Twins resulting from the division of a single zygote after fertilization; also called identical twins; they are genetically similar.