Answers, BIO 2320, Female

Objectives – 4, BIO 2320, Female Reproductive SystemAnswers


C. FEMALE REPRODUCTIVE SYSTEM

1.Ovary

2.Ovarian ligament from ovary to uterus, Mesovarium from ovary to broad ligament, suspensory ligament from ovary to dorsal body wall

3.Oogonia are diploid and can undergo mitosis to replenish themselves in the fetus. Oogonia then become destined to under go meiosis and become primary oocytes. They start through meiosis I and stop halfway through and this is the state at birth. At puberty the primary oocytes finish their meiosis I and start through meiosis II. However, they stop halfway through meiosis II & do not finish until just prior to fertilization. At this time, the secondary oocyte briefly becomes an ovum (haploid) and then is fertilized to become zygote (diploid). Yes, females are born with all of the eggs (primary oocytes) that they will ever have.

4.These structures are found in the ovary. Follicle = bag. It is the oocyte plus all of the surrounding cells. After ovulation, the secondary oocyte is ejected and the follicle cells stay behind in the ovary. This is the corpus luteum.

5.Starting with puberty and ending at menopause, FSH causes the follicles to mature. They enlarge, and as they do, they release estrogen. Then, at about day 14, the female ovulates leaving behind the corpus luteum which continues to make estrogen but now also makes progesterone.

6.Discharge of an egg from the ovary, day 14 (day 1 is the first day of menstrual bleeding of a 28 day cycle)

7.Oviduct = Uterine tube = Fallopian tube with its widened infundibulum and fingers called fimbriae.

8.Oviduct

9.Broad ligament

10.Inferior “doorway” to uterus

11.Perimetrium (serosa), Myometrium, Endometrium

12.GnRH made by hypothalamus starts puberty and starts the monthly ovarian/menstrual cycle. Its role is to stimulate the Ant. Pituitary to make FSH & LH. FSH causes follicle maturation over the first couple of weeks and by day 14 the LH levels spike resulting in ovulation. As the follicle enlarges it also makes more and more estrogen which stimulates increased thickness of the endometrium and stimulates GnRH production. After ovulation, the corpus luteum makes both estrogen and progesterone. The 2 hormones cause a very thick endometrium and work to inhibit the other hormones by stopping GnRH production. Without supportive hormones such as FSH, the corpus luteum dies by about day 28. Without progesterone & estrogen to support it, the endometrium also “dies” and is sloughed off during the first 3-5 days of the next cycle.

13.See above – regarding the endometrium

14.Menarche is first menstrual cycle marking puberty in girl; menopause is when the female runs out of eggs and therefore will not have follicular hormones present such as estrogen & progesterone.

15.Fornix is the recess in the vagina that surrounds the cervix, the hymen is a thin vascularized membrane at the inferior end of the vagina that must be ruptured for intercourse. The vagina is sometimes referred to as the birth canal.

16.Vestibule is the opening that houses the vagina & urethral orifice; Labia majora are the lateral folds that are skin, labia minora are mucous membrane “lips”, clitoris is erectile tissue homologous in embryology to the penis of the male and is located at anterior junction of labia minora and mons pubis is region near pubic bones.

17.Pectoralis major

18.Anatomy is lobes & smaller lobules. In the lobules are alveoli that make milk, milk then travels through lactiferous ducts and a widened sinus to the nipple. Lactation is the function

19.Milk production

20.Human Placental Lactogen prepares the mammary glands during pregnancy. Prolactin, made by ant. pituitary causes milk production & the actual sucking by the baby stimulates more release of prolactin. Oxytocin is the hormone that is made by the hypothalamus and released by post. pituitary. It causes milk release or let down. It is present during childbirth, and then its continued release comes from the baby sucking on the nipples.

21.Same physiology as male but no ejaculation.

Urinary, Reproduction and Development flash cards: https://www.brainscape.com/packs/4448735/invitation?referrer=792771