Question

no explaination is needed, I will give a thumb, thanks'

16. In close comparisons, external fertilization often yields more offspring than does Internal fertilization, but Internal fertilization offers the advantage that a) It is the only way to ensure the survival of the species b) It requires less time and energy to be devoted to reproduction. d the smaller number of offspring produced often receive a greater amount of parental investment. d) It permits the most rapid population increase 17. Most flatworms, including parasitic liver flukes, are hermaphrodites where zygotes form as the result of a) Internal fertilization b) external fertilization c) parthenogenesis. d) eggs and sperm mixing together in wastewater 18. Asexual reproduction results in greater reproductive success than does sexual reproduction a) when pathogens are rapidly diversifying b) when a species is in stable and favorable environments. c) when there is some potential for rapid overpopulation. d) when a species is expanding inte diverse geographic settings. 19. Assume that successful reproduction in a rare salamander species, wherein all Individuals are females, relies on those females having access to sperm from males of another species but that the resulting embryos show no signs of a genetic contribution from the sperm. In this case, the sperm appear to be used only for a) morphogenesis b) epigenesis c) egg activation d) cell differentiation. 20. The cortical reaction functions directly in the a) formation of a fertilization envelope. b) production of a fast block to polyspermy c) release of hydrolytic enzymes from the sperm cell d) generation of a nerve-like impulse by the egg cell The vegetal pole of the zygote differs from the animal pole in that a) the vegetal pole has a higher concentration of yolk. b) the blastomeres originate only in the vegetal pole. c) the posterior end of the embryo forms at the vegetal pole d) the vegetal pole cells undergo mitos but not cytokines's. mar to the chiocyte of a 22 In terms of food capture, which sponge cel Cnidarian? al amoebocyte b) Choanocyte c) epidermal cell d) pore cell

Answer 1

1)c) the smaller number of offspring produced often recieves a great parental investment.

2)a) internal fertilization

3)b) when a species in a stable and favourable environment.

4)c) egg activation

5)a) formation of fertilization envelope.

6)a) the vegetal pole has higher concentration of yolk

7)b) choanocyte