Chapter 28 HW Growth and Development
How long is the secondary oocyte viable and capable of being fertilized after it is ovulated?
12-24 hours
At what point is meiosis II completed for the female gamete?
fertilization
During which stage of labor is the fetus delivered?
expulsion stage
The embryo is directly enclosed in and protected by the amnion.
True
Which hormone maintains the viability of the corpus luteum?
human chorionic gonadotropin
Which of these is the innermost (closest) structure that completely surrounds the embryo?
amnion
Ex.
The amniotic fluid, found in the amnion and intimate with the embryo, protects the embryo from physical trauma and maintains a constant homeostatic temperature.
The trophoblast is mostly responsible for forming the ________.
placental tissue
What cellular area shown in the figure secretes human chorionic gonadotropin (hCG)?
syncytiotrophoblast
Ex.
Syncytiotrophoblast cells begin to secrete human chorionic gonadotropin (hCG) following implantation.
Thalidomide was once used to treat intense nausea and morning sickness in pregnant women. Unfortunately, if administered at certain points during gestation it resulted in limb malformation. This drug is an example of a(n) ________.
teratogen
Which of the following is the longest stage of labor, lasting 6-12 hours or more?
dilation stage
Ex.
The dilation stage often lasts the longest, up to 12 hours or more.
The period from fertilization through week eight is called the embryonic period.
True
What role does oxytocin play in promoting labor?
Oxytocin stimulates the uterus to contract.
Ex.
Oxytocin from fetal cells, and eventually the posterior pituitary, stimulates the uterus to contract both directly and through the release of prostaglandins.
Once sperm are deposited into the vagina, the sperm's motility must be enhanced and they must be prepared to release hydrolytic enzymes from their acrosomes. What is this process called?
capacitation
Ex.
Sperm must undergo capacitation in order to gain the ability to penetrate and fertilize an oocyte.
Which of the following implants in the mucosa of the endometrium?
blastocyst
Ex.
The blastocyst implants after about seven days. It consists of a hollow ball of cells with a smaller, inner cell mass pressed to the inside wall.