Anatomy Final-CH28
Once sperm are deposited into the vagina, sperm motility must be enhanced and they must be prepared to release hydrolytic enzymes from their acrosomes. What is this process called?
capacitation
Which of the following occurs 21-30 weeks into pregnancy, during the fetal period?
Blood cell production in the bone marrow.
Proteases and acrosin are enzymes. How do they function in reproduction?
They act to break down the protective barriers around the egg, allowing the sperm to penetrate.
correct statement about fertilization
Millions of sperm cells are destroyed by the vagina's acidic environment.
A zygote is usually formed within the uterus.
false
Together, what do the decidua basalis and the chorionic villi form?
placenta
Implantation begins six to seven days after ovulation.
true
Which germ layer gives rise to the nervous system?
ectoderm
Which of the following INCORRECTLY matches an embryonic structure with its function?
yolk sac: provides nutrients to developing embryo
Muscle tissue is formed by the ________.
mesoderm
Of the three germ layers, the mesoderm forms the most body parts.
true
Which fetal vascular shunt directly connects the right atrium to the left atrium so as to bypass the nonfunctional lungs?
foramen ovale
What does the hormone relaxin promote?
Relaxin promotes the widening and increased flexibility of the pelvic ligaments and pubic symphysis.
Because of the increased bulkiness of the anterior abdomen and the change in a pregnant woman's center of gravity, what type of spinal curvature do many pregnant women develop?
excessive lordosis of the lumbar spine
Which of the following is the primary germ layer that forms the basis for the musculoskeletal system?
mesoderm
Which of the following occurs 9-12 weeks into pregnancy, during the fetal period?
Sex is readily detected by observing the genitals.
Teratogens may cause anatomical abnormalities in an embryo, but do not cause anatomical abnormalities in a pregnant woman because ______.
organogenesis does not occur in an adult
Which body system of a pregnant woman undergoes the most dramatic physiological changes during pregnancy?
cardiovascular system
What role does oxytocin play in promoting labor?
Oxytocin stimulates the uterus to contract.
The placenta and its attached fetal membranes are collectively called the afterbirth.
true
What does the ductus arteriosus become at birth?
ligamentum arteriosum
During pregnancy, which hormone is responsible for stimulating maturation of the breast for lactation?
human placental lactogen (hPL)
leads to the development of a morula and then a blastocyst
cleavage
embedding of the blastula in the uterine wall
implantation
leads to the formation of the first cell of the new individual
fertilization
fertilization
leads to the establishment of the three primary germ layers
gastrulation
Leads to enhancement of sperm motility and increasing membrane fragility to enable enzyme release from acrosomes.
capacitation