You Are Observing a Developing Embryo Under a Microscope and See

question 17

Multiple Choice

You are observing a developing embryo under a microscope and see that it has a space in the middle of the endoderm, but no features of a notochord are present. In which stage of development is this embryo?

• A) zygote
• B) blastula
• C) gastrula
• D) fetus

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Definitions:

SRY

A gene on the Y chromosome responsible for the initiation of male sex determination in humans.

Y Chromosome

A sex chromosome that is typically present in male individuals and is one of the determinants of male biological sex in humans.

X Chromosome

One of the two sex chromosomes, with females typically having two X chromosomes and males having one X and one Y chromosome.

Menarche

The first menstrual period in a person's life, marking the onset of reproductive capability.