BIO 351 EXAM 2 REVIEW QUESTIONS AND ANSWERS

BIO 351 EXAM 2 REVIEW QUESTIONS AND
ANSWERS

The Primitive streak plays a key role in gastrulation. Where is the primitive
streak located in the 24 hr old chick embryo? - ANSWER B

Which of the following cell types is formed from epiblast cells that migrate
through the primitive streak? - ANSWER Mesoderm - the mesoderm forms the
epiblast cells migrating through the primitive streak.
- Remember that the definitive endoderm also forms the migration through the
primitive streak.

Why isn't the ectoderm formed from epiblast cells that migrate through the
primitive streak? - ANSWER The ectoderm forms from the remaining epiblast
that does not migrate through the primitive streak

Why isn't the primary hypoblast formed from epiblast cells that migrate through
the primitive streak? - ANSWER The primary hypoblast forms from islands of
cells ventral to the epiblast.

All the cells of the embryo proper (all the cells in your body now) derive from
which of the following cells? - ANSWER Epiblast

Which of the following is the epiblast? - ANSWER Refer to image on question
4 on Sep. 17th lecture questions,

Answer: C

Which of the following is the anterior visceral endoderm? - ANSWER C

In the mammalian embryo, which structure is essential to set up the anterior-
posterior axis? - ANSWER Anterior visceral endoderm

Inner cell mass - ANSWER determines the proximal-distal (dorsal-ventral)
axis

Node - ANSWER key to forming left-right asymmetry