Sperm are produced in the man's body in winding tubules within the:
epididymis
urethra
testes
fallopian tubes
Long, threadlike structures made of protein and nucleic acid containing hereditary materials are known as :
genomes
chromosomes
DNA
genes
During ejaculation, as the sperm pass out of the man's body through the penis, secretions that fuel and protect the sperm are also released from the:
Seminal vesicles and prostate gland
Androgens and prostate gland
Prostate gland and urethra
Seminal vesicles and urethra
The placenta is the organ that:
transfers maternal nutrients to the fetus.
protects the fetus against infectious organisms.
directly connects the fetal and maternal blood supplies.
connects the embryo to the vaginal wall.
As a result of cleavage, the zygote becomes transformed into a hollow ball of cells called the:
mitosis
blastocyst
chorion
ectoderm
The prenatal development of the organs of the fetus assume their specialized functions during the :
germinal stage
embryonic stage
fetal stage
critical stage
What is puberty?
Partitioning of replicated chromosomes into two identical groups.
Prenatal development of the organs of the fetus.
Adults undergo the process of sexual maturation.
Reproductive cycle in the female primates.
The principal male sex hormones are:
estrogen and progesterone.
estrogen and testosterone.
testosterone and androsterone.
testosterone and semen.
About what percent of zygotes die shortly after fertilization?
10 percent
23 percent
33 percent
43 percent
The optimal time for fertilization to occur within the menstrual cycle is:
at the beginning of the cycle.
at the middle of the cycle.
at the end of the cycle.
any time during the cycle.