chapter 29 Flashcards
The fetus develops within a membranous cavity called the __________.
amnion allantois chorion decidua
amnion
Which placental hormone keeps the myometrium relaxed during pregnancy?
progesterone placental lactogen relaxin estrogen
progesterone
Implantation of the __________ occurs about 7 days after __________.
blastocyst; ovulation blastocyst; fertilization zygote; ovulation zygote; fertilization
blastocyst; fertilization
The zygote forms when __________.
the female pronucleus complete meiosis II the male and female pronuclei fuse sperm penetrates the oocyte the spermatozoan contacts the oocyte
the male and female pronuclei fuse
Which of these pairs of terms is mismatched?
second trimester - embryogenesis first trimester - placentation third trimester - largest size gain second trimester - organogenesis
second trimester - embryogenesis
The alternate forms of any one gene are called
heterozygous. autosomes. alleles. homozygous. homologous.
alleles.
Stretching of the cervix causes an increase in the blood levels of
estrogen. chorionic gonadotropin. oxytocin. relaxin. progesterone.
oxytocin.
Which of these hormones is produced by the placenta?
relaxin progesterone human chorionic gonadotropin All of these hormones are produced by the placenta.
All of these hormones are produced by the placenta.
Which is the correct sequence of labor and delivery stages, arranged from first to last?
parturition, dilation, placental dilation, parturition, placental dilation, placental, parturition placental, parturition, dilation
dilation, parturition, placental
If both mother and father are heterozygous for a trait showing simple dominance, what is the probability that one of their future children will show that trait?
25 percent zero percent 100 percent 75 percent
75 percent
Contact of a sperm with the oocyte membrane causes
extrusion of the second polar body. completion of the second meiosis. oocyte activation. membrane fusion. All of the answers are correct.
All of the answers are correct.
If one parent is homozygous for a trait that exhibits simple dominance and the other parent is heterozygous for that trait, their offspring will have a __________ chance of possessing that trait.
100% 0% 50% 25%
100%
__________ is the gradual modification of the organism from __________ to maturity.
Development; birth Differentiation; birth Differentiation; conception Development; conception
Development; conception
Development is the gradual modification of body form and function from __________.
birth to maturity conception to birth conception to senescence conception to maturity
conception to maturity
The period of gestation that is characterized by rapid growth and fat accumulation is the __________ trimester.
first second postnatal third
third
Which these oocyte processes is not activated by sperm penetration?
membrane depolarization influx of sodium ions discharge of exocytotic vesicles softening of the zona pellucida
softening of the zona pellucida
After fertilization, the first cell division is completed
within the hour. about 6 hours later. in 12 hours. more than a day later. within a few seconds.
more than a day later.
Which of the following is not part of oocyte activation?
membrane depolarization discharge of exocytotic vesicles release of calcium ion from smooth ER influx of sodium ion softening of the zona pellucida
softening of the zona pellucida
The site where fertilization normally occurs is in the
upper one-third of the uterine tube. fimbrae. union of the vagina and uterus. uterine wall near the fundus. cervix.
upper one-third of the uterine tube.
The developmental period that is the period of all embryological and early fetal development is
first trimester. third trimester. adolescence. second trimester. infancy.
first trimester.
The period of gestation when the rudiments of all major organ systems are established is the ________ trimester.
fourth fifth first third second
first
Which placental structure provides surface area for active and passive exchange of gases, nutrients, and waste products between the fetal and maternal bloodstreams?
chorionic villi amnion yolk sac myometrium
chorionic villi
Which set of blood vessels carries blood that is deoxygenated and transports fetal waste products from the fetus to the placenta?
gonadal arteries umbilical veins gonadal veins umbilical arteries
umbilical arteries
Which set of blood vessels carries blood that is oxygenated, filled with organic nutrients, and low in waste products from the placenta back into the fetus?
gonadal arteries umbilical veins umbilical arteries gonadal veins
umbilical veins
