Pregnancy and Human Development Flashcards
What is the gestation period?
date from the last menstrual period until birth (usually around 280 days)
From what weeks is the fertilized egg called an embryo?
from week 8 until fertilization
What is capacitation?
the process that sperm undergo within the uterine tube for 10 hours before they can fertilize the egg
What is the window of opportunity?
two days to 14-24 hours before ovulation is the ideal time to fertilize and egg
What is the fast block of the egg?
causes the egg membrane voltage to change so it cannot bind additional sperm
What is the slow block of the egg?
makes it so the egg membrane cannot be penetrated by any more sperm
What is cleavage?
the rapid mitotic divisions of the zygote in the first three days while it moves down the uterine tube
What is a blastocyst?
fluid filled sphere composed of hundreds of cells
What secretes the progesterone and what does the progesterone do?
The corpus luteum and progesterone keeps the uterus quiet
When does the embryoblast begin to get called an embryo?
following embryogenesis when the three germ layers are formed
What does the ectoderm form?
nervous system, epidermis, pineal and pituitary glands, epithelia of nasal cavity, oral cavity, and nasal canal
What does the mesoderm form?
skeleton, cartilage, glood, tissue of kidneys, urinary and sex organs
What does the endoderm form?
epithelium of digestive and respiratory tracts, thyroid and parathyroid glands, thymus, epithelial components of the accessory reproductive and digestive glands
What is the amnion and what does it do?
translucent sac that encloses the embryo in amniotic fluid to protect the embryo
What does the yolk sac do?
helps with the development of the digestive tracts and produces the first blood and germ cells of the embryo
