1 A) head B) tail C) midpiece 2 A) the blastocoel develops B) three layers of cells are present C) the egg nucleus fuses with the sperm nucleus D) the ectoderm and endoderm are present 3 A) ectoderm B) endoderm C) mesoderm 4 A) 3, 2, 1, 4 B) 2, 4, 3, 1 C) 2, 3, 1, 4 D) 3, 2, 4, 1 5 A) blastocoel B) coelom C) hemocoel D) archenteron 6 A) Human chorionic gonadotropin B) Oxytocin C) Androgens (precursor of estrogen) D) Prostaglandins 7 A) lungs B) liver C) kidneys D) heart 8 A) one B) two C) three D) four 9 A) notochord B) umbilical cord C) pharyngeal arches D) limb buds 10 A) second B) fifth C) twelfth D) twentieth 11 A) chorion B) allantois C) amnion D) yolk sac 12 A) estrogen B) inhibin C) follicle stimulating hormone D) human chorionic gonadotropin 13 A) oviduct B) uterus C) vagina 14 A) morphogens B) bicoid genes C) homeotic genes 15 A) getting adequate exercise during pregnancy. B) increasing Vitamin D intake during pregnancy. C) consuming adequate amounts of folic acid during pregnancy. D) avoiding alcohol and smoking during pregnancy. 16 A) If absent during certain stages of fetal development, physical defects may result. B) Apoptosis is an important part of morphogenesis. C) Proteases and nucleases that slice up proteins and DNA in the cell are produced. D) It allows cells to have a longer life span than they normally would. 17 A) morphogenesis B) gastrulation C) induction D) differentiation 18 A) Ectoderm – nervous system B) Mesoderm – lining of the digestive and respiratory tract C) Endoderm – musculoskeletal system 19 A) the kidneys become larger and more efficient at filtering waste. B) the thymus decreases in size and is replaced by fat and connective tissue. C) there is more adipose tissue in the subcutaneous layer. D) the skin becomes thicker and more flexible. 20 A) Preprogrammed theories B) Endosymbiotic theory C) Damage accumulation theories
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