In a sample of double-stranded DNA, 30 \%30%30, percent of the nitrogenous bases are adenine (A). What percentage of the nitrogenous bases in the sample are thymine (T)?

The number of thymine (T) should be the same as adenine(A). That means we have 30% A and 30%T. 100-30-30=40%(G and C). Guanine(G) and cytosine(C) are also equal in number so we have 30%A(adenine) 30%T(thymine) 20%G(guanine) and 20%C(cytosine)

the corpus luteum secretes estrogens and progesterone. the latter hormone causes changes in the uterus that make it more suitable for implantation of the fertilized ovum and the nourishment of the embryo. if the egg is not fertilized, the corpus luteum becomes inactive after 10–14 days, and menstruation occurs.

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