Name and describe the four stages of development of the nervous system. Give an example of how exposure to certain drugs or toxins can affect development.
What will be an ideal response?
Development begins with cell proliferation, which is when neurons divide and rapidly multiply at a rate of 250,000 new cells per minute. The new cells must then go through the stage of migration, since cells are generated in the ventricular zone rather than in their final destinations. During migration, neurons are guided to their final destinations by radial glial cells. Circuit formation is the next stage of nervous system development and occurs when the axons of new cells grow toward other cells and synapse with them. Growth cones form at the tips of axons to assist in this process. The last stage of nervous system development is circuit pruning, when the nervous system is refined by removing unneeded synapses and neurons. Neurotrophins are released from postsynaptic neurons to promote the growth and survival of synapsing cells, while neurons that are not forming active synapses die off. Both fetal alcohol syndrome and ionizing radiation can negatively impact the brain during development. Alcohol exposure can result in fetal alcohol syndrome by disrupting the migration of neurons, resulting in malformed brains. Both cell proliferation and migration are disrupted by exposure to ionizing radiation. The results of these disruptions are intellectual impairment.
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According to Freud's theory, resistance involves a patient refusing to take any medication
Indicate whether the statement is true or false.
An observed score is comprised of the a. true score + measurement error (method error + trait error). b. true score + method error only
c. true score + trait error only. d. measurement error (method error + trait error).
Jamal and Mandy took the Scholastic Aptitude Test (SAT) in different locations. Later, when they discussed the test, they discovered that they each had been allowed exactly the same amount of time and that they each had heard exactly the same instructions at the start of each section. In this example, the administration of the SAT:
a. had high test-retest reliability b. did not have construct validity c. did not have test-retest reliability d. was standardized
Cardiorespiratory fitness enhances psychological well-being. A combination of ____ aerobic exercise and ____ resistance training is the antidote
a. vigorous, moderate c. moderate, light b. light, vigorous d. light, moderate