Describe how the brain transports essential chemicals.
What will be an ideal response?
The brain has several transport mechanisms. Small, uncharged molecules, including oxygen and carbon dioxide, cross freely. Water crosses through special protein channels in the wall of the endothelial cells. Also, molecules that dissolve in the fats of the membrane cross easily. Examples include vitamins A and D and all the drugs that affect the brain-from antidepressants and other psychiatric drugs to illegal drugs such as heroin. How fast a drug takes effect depends partly on how readily it dissolves in fats and therefore crosses the blood- brain barrier.For a few other chemicals, the brain uses active transport, a protein-mediated process that expends energy to pump chemicals from the blood into the brain. Chemicals that are actively transported into the brain include glucose (the brain's main fuel), amino acids (the building blocks of proteins), purines, choline, a few vitamins, iron, and certain hormones.
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Regarding prejudice and direct experiences, which of the following statements is FALSE?
a. By the time they are three years old, many children show signs of race bias. b. Prejudices that occur when members of another social group are perceived as a threat to one's own interests are referred to as group prejudices. c. Once prejudices are established, they prevent us from accepting more positive experiences that could reverse the damage. d. Subtle influences, such as parents' attitudes, the depiction of people in books and on TV, and exposure to children of other races, can have an impact on one becoming prejudiced.
Renaldo and Clara spend time with their baby, teaching her to say what she wants and to tell her parents how she feels. What is this style of speech called?
A. expressive B. underextension C. overextension D. referential
According to Robert Sternberg, the IQ score derived from traditional intelligence tests relates well to which aspect of the triarchic theory?
A. emotional and interpersonal relationship success B. adult career success C. success in adult relationships D. academic success
The definitional approach to categorization
a. is not well suited for geometrical objects but works for familiar everyday objects. b. sets definite criteria called family resemblances that all category members must have. c. doesn't work well for most natural objects like birds, trees, and plants. d. was proposed to replace the prototype approach.