Describe the function and purpose of the placenta and explain what types of harmful substances can break through the placental barrier and possibly harm the fetus
What will be an ideal response?
Mother and embryo have separate circulatory systems. The pancake-shaped placenta contains a membrane that acts as a filter that permits oxygen and nutrients to reach the embryo from the mother, and permits carbon dioxide and waste products to pass to the mother from the embryo. The mother then eliminates them through her lungs and kidneys. Germs that cause syphilis and German measles and drugs like aspirin, narcotics, alcohol and tranquilizers, can cross the placenta and affect the fetus.
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Regarding the goals of therapy, the goal of traditional psychoanalysis was to
a. gain better self-knowledge, while client-centered therapy sought to help people to use their potentials fully. b. cure the patient, while client-centered therapy sought to reduce symptoms. c. change thinking patterns, while client-centered therapy sought to change observable behavior. d. change observable behavior, while client-centered therapy sought to change thinking patterns.
Which of the following statements best describes the propagation of action potentials? a. The action potential is reproduced repeatedly down the length of the axon
b. One action potential is formed at the axon hillock, and this same signal travels down the length of the axon. c. When the axon hillock reaches threshold, action potentials are simultaneously formed down the length of the axon. d. One action potential is formed at the axon hillock, triggering the movement of chemical messengers that travel the length of the axon.
A child's ability to map words onto concepts or objects after only a single exposure to them is called ____________
A) hyper learning B) pragmatics C) imitation D) fast mapping
In the 1960s, employment ads for women would have likely presented which job opportunity?
A. police officer B. secretary C. bank officer D. legal counsel