During the second stage of prenatal development, the blastocyst forms three cell layers. What are names of each and what does each layer eventually become?
What will be an ideal response?
The ectoderm is the outer layer of the cell mass, and during the embryonic stage it gives rise to the nervous system
(including the brain and spinal cord), sensory receptors, and outer skin layers. The mesoderm, or middle layer,
becomes the circulatory system, skeleton, muscles, excretory system, reproductive system, the outer layer of the
digestive tract, and the inner layer of skin. The endoderm, or inner layer, will eventually become the respiratory
system and the remainder of the digestive system.
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In Freud's view, if parents are too ______ during toilet training, children may become obstinate, stingy, and excessively orderly, and if they are too ______, their children may become messy, unorganized, and sloppy as adults
a. strict; strict c. lenient; strict b. strict; lenient d. lenient; lenient
Assessing sexual orientation is, as a whole, ___________
a. still in need of much investigation and research b. something we understanding clearly c. something we have no reliable research with which to draw conclusions d. none of the above