The embryo becomes implanted in the endometrium of the uterus due to:
a. special receptors on the endometrium to which the blastocyst attaches.
b. enzymes secreted by the trophoblast, which erode an area of the endometrium for entry of the embryo.
c. special phagocytic cells in the endometrium, which engulf the embryo.
d. the sticky coat of the zona pellucida, which adheres to the endometrium.
e. the action of hCG secreted by the embryo.
b
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All of the following are non-protein electron carriers EXCEPT
A) FADH2. B) FMNH2. C) cytochromes. D) quinones.
Which of the following is not true of gene regulation by DNA looping?
A. The precise distance between the regulatory sequence and the promoter is important. B. It can result in gene repression. C. It can result in gene activation. D. It can result in the regulation of a gene even thousands of base pairs away from the regulatory site.
Which term refers to an individual with identical alleles of a particular gene?
a. Genotype b. Heterozygous c. Homozygous d. Gene e. Phenotype
Polygyny is often positively correlated with:
a) territoriality and mate guarding. b) equal parental investment and equal choosiness in mate selection. c) sexual monomorphism and variation in male reproductive success. d) sexual dimorphism and variation in male reproductive success. e) sexual dimorphism and variation in female reproductive success.