At what stage of pregnancy does an embryo show a beating heart and a complete central nervous system?
a. 8 weeks
b. 12 weeks
c. 16 weeks
d. 20 weeks
e. 24 weeks
ANS: A
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What is the strcutre and function of glycerol molecules?
a. an alcohol containing 3 carbons; it is the backbone of a triglyceride molecule b. a fat-relaed substacne containing phosphorus, fatty acids, and nitrogen-containing base; it is an essential part of every cell c. a fatty acid molecule that contains one carbon-carbon double bond; it may be a component of triglyceride
What type of fatty acid chain contains one double carbon bond?
A) saturated B) polyunsaturated C) sterol D) monounsaturated
Which of the following foods is the most nutrient-dense per serving?
A. Leafy greens B. Grape drink C. Refined grains D. French fries
Which of the following physiological changes is a result of catabolic chemical reactions?
A. Muscle mass enlargement that occurs after lifting weights B. Weight gain that occurs after 3 weeks of overeating C. Bone growth that occurs during adolescence D. Muscle loss that normally occurs in older adults