Are cortical cells considered a really fibroblast cells or fibroblast like cells and what is the difference?
They are interstitial cells similar in shape to fibrobasts. They are important source of estrogens.
Excuse me doctor in the proliferative phase of the menstrual cycle it's mentioned that "the endometrium resumes its covering simple columnar partially ciliated epithelium" so what was the epithelium of the basal zone so that the estrogen would change it to simple columnar.
The epithelium is simple columnar partially ciliated, it sheds completely in the menstrual (destructive) phase with no epithelium. The basal zone is not covered by epithelium, it is formed of basal pasts of the glands+ CT.
What is the nature of secretion of endometrial glands?
Proliferative phase: The simple tubular glands proliferate to form numerous glands which start to secrete mucous.
Secretory phase: the glands produce a copious glycogen rich secretion which is an important source of nutrition for the fertilised ovum.
Excuse me doctor in the destructive phase of the menstrual cycle the spiral arteries undergo constriction which causes ischemia & death of the wall of the arteries & cells of the endometrium . It's logical to cause death to the cells of the endometrium due to ischemia but the wall of the spiral arteries shouldn't die it's just a constriction in the arteries .................. Thanks in advance
The severe constriction leads to ischemia and death of the superficial layer and the spiral vessels themselves, they undergo necrosis.
I can't understand this statement "Stroma become edematous and their fibroblast enlarge and show features of protein synthesizing cells > these changes are refered to as decidual reaction"
Decidua= endometrium of pregnancy.
The endometrium becomes thick edematous and the fibroblasts secrete substances essential for nourishment of the implanted fertilized ovum.
Edematous= contains excess tissue fluid, for nourishment of the zygote, tissue fluid rich in nutrition
when does 2nd meiotic division begin and complete?
The first meiotic division is not completed untlil just before ovulation.
One daughter cell becomes secondary oocyte and the other forms the first polar body.
The secondary oocyte is arrested at metaphase in the second meiotic division just before ovulation.
This division is arrested at metaphase and completed only if the secondary is penetrated by a spermatozoon.
If fertilization occurs, the second meiotic division forms a mature ovum and second polar body.
What are the things that do pass the placental membrane?
Gases: O2, CO2, CO;
Nutrients: Amino acids, glucose, fatty acids, vitamins, electrolytes. IgG.
Antibodies: Immunity to diptheria, smallpox, and measles.
Drugs: e g: Thalidomide causes defects in limb/ear.
TORCH infection agents: Treponema pallidum (syphillis) (only bacterium).
Waste products: (urea, uric acid, billirubin)
What are the things that do not pass the placental membrane?