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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The adolescent growth spurt is triggered by
a. the child's psychological "will to grow.". b. growth hormone in both boys and girls. c. growth hormone in boys and estrogen in girls. d. estrogen in boys and growth hormone in girls.
It seems that everywhere you go you run into terms that were originally proposed by Sigmund Freud. On television they are talking about Freudian slips, your professor mentions the pleasure principle,
and a friend claims that you are always using defense mechanisms. Briefly describe the major elements of Freudian psychoanalysis—the drives that motivate behavior, the stages of psychosexual development, the structure of personality, and the defense mechanisms. What will be an ideal response?
Which is not one of the basic kinds of taste buds?
(a) salt (b) sour (c) texture (d) bitter (e) sweet
Of the normal six layers of the cortex, which layer(s) is/are usually associated with sensory functions?
A. I B. II/III C. IV D. V/VI