Reproductive System Flashcards
Acrosin
Enzyme that activates the sperm
Neuraminidase and Hyaluronidase
Enzymes that help sperm penetrate the corona radiata and zona pellucida of ovum
Where are sperm produced?
Sperm are produced by germ cells in the seminiferous tubules
What 2 functions do the Interstitial Cells of Leydig have?
- Secrete testosterone used to develop secondary sex characteristics
- Work with FSH to stimulate sperm
Sertoli Cells
Support cells joined tightly together to form the blood-testis barrier
How does the blood-testis barrier protect sperm from the immune system?
It prevents an immune response towards the surface antigens on sperm
Anti-Mullerian Hormone (AMH)
-Secreted by Sertoli cells during the early stages of fetal life
Result: The male reproductive duct develops; thus if mullerian duct developed, the women’s reproductive duct would develop
Inhibins and Activins
- Secreted by Sertoli cells after puberty
- They work together tp regulate FSH secretion
Androgen Binding Protein
- AKA Testerone binding globulin
- Increases testosterone concentration in the seminiferous tubules to stimulate spermatogenesis
Estradiol
Aromatase from Sertoli cells convert testosterone to 17 beta estradiol to DIRECT spermatogenesis
Glial cell line-derived neurotrophic factor (GDNF)
- Secreted by Sertoli cells
- Functions in promoting undifferentiating spermatogonia, which ensures stem cell self-renewal during the perinatal (after birth) period
ETS Related Molecule
- Secreted by Sertoli cells
- AKA ERM transcription factor
- Needed for maintenance of the spermatogonial stem cell in the adult testis
Transferrin
- Secreted by Sertoli cells
- A blood plasma protein for iron ion delivery
Travel of Sperm
Leave the Seminiferous Tubules via efferent ducts-> epididymis to mature for 2 weeks consuming fructose-> vas deferens
The Dartos Muscle
- Lines the scrotum
- Responsible for contraction of the scrotum when cold and relaxation when hot; also forms a septum in the scrotum
Vasectomy
Tying and cutting the vas deferens for contraceptive purposes; ONLY SPERM AND FRUCTOSE are being cut off (not the 3 glands)
Vasovasostomy
Reversal of a vasectomy
The Cremaster Muscle
- Within the scrotum
- AKA the ductus deferens or the spermatic duct
- It leaves the epididymis carrying sperm and fructose during ejaculation
What is semen made of?
Sperm, secretions from the seminal vesicle, prostate, and cowper’s/bulbourethral gland
Seminal Vesicle Secretions
An alkaline, viscous fluid high in fructose, prostaglandins, and fibrinogen
What does fibrinogen do?
It coagulates and thus thickens the semen
Prostate Secretions
A milky secretion containing citric acid (used by sperm make ATP), enzymes that work with fibrinogen to coagulate semen and seminal plasmin
*Makes the semen white
Seminal plasmin
Antibiotic that destroys certain bacteria; Keeps the bacteria in the vagina under control to protect the entering sperm and ensure fertilization
Cowper’s/ Bulbourethral Gland
An alkaline liquid used to lubricate the urethra for smooth passage of semen and to neutralize vaginal and residual urethral acidity
What is the name and function of the erectile tissue in the penis?
Creation of sensation
2: Corpus spongiosum(surrounds the urethra) and corpus cavernosum(surrounds the deep artery)
How is an erection brought about?
The PNS causes vasodilation and gorging of the erectile tissue
How is ejaculation brought about?
The SNS stimulates the bulbospongiosus muscle to contract and force semen out. The contraction is under the control of a spinal reflex in the saccral spinal nerves.
Glans Penis
The head of the penis and contains the most concentrated mass of nerve endings for stimulation.
Why is a semen analysis done?
If there is a problem with infertility
Semen Analysis looks at…
1) Volume- 2.5-5 cc(ml)
2) Sperm Count- 50 to 150 million/cc; 20 is considered infertility
3) pH- should be alkaline
4) Morphology- acceptable malformations of sperm are 30-35%; more leads to infertility
5) Liquefaction should occur in 10-20 minutes (slowed= enzyme problem)
6) Motility- how well the sperm move and properly
Orchitis
Inflammation of the testes; can lead to a zero sperm count
Sperm in the Female Reproductive Tract
- viable in the tract for 24-72 hours after ejaculation
- once here, they are further activated (CAPACITATION)
Lining of the Vagina
- Mucous epithelial tissue to reduce friction
- Helps avoid DYSPAREUNIA (painful intercourse)
- And during stimulation, Bartholin’s glands secrete a lubricant
The Clitoris
- the female equivalency to the penis in the function of stimulation and NOT FERTILIZATION
- It is erectile tissue
The Cervix
The neck of the uterus; its opening is the “OS”
Nulliparous vs. Parous Cervix
- Nulli: never delivered a baby vaginally; small circle os
- Parous: delivered at least 1 baby vaginallu
Layers of the Uterus
Out to in: Perimetrium, Myometrium (smooth muscle and thickest layer), Endometrium
The Endometrium
- Shed each month during the period
- Highly vascularized and has 3 components
Components of the Endometrium
1) Innermost layer composed of simple columnar epithelium lines the lumen
2) An underlying endometrial stroma; a very thick region of lamina propria (areolar CT)
3) Two Layers: Stratum functionalis- lines the uterine cavity and sloughs off during menstruation; Stratum basalis- the permanent layer that gives rise to a new stratum funct. after each period
Where is the ovum(egg) housed?
The ovarian follicle
The Travel of the Egg
Egg released during ovulation-> trapped by the fimbriae of the fallopian tube-> movement of the egg towards the uterus via cilia
Embryo Implantation
- After fertilization and occurs in the fallopian tube usually on day 9
- Implants into the posterior uterine wall
How do identical twins occurs?
- AKA monozygotic, maternal
- Came from 1 zygote, 1 egg, 1 sperm, 1 set of genes
- Occur due to the splitting of the embryo after one cleavage
How do non-identical twins occur?
- AKA dizygotic, fraternal
- From both ovaries, 2 eggs viable to be fertilized; the result of 2 ovulations and 2 sperm
- Gender depends on law of independent assortment
Corpus Luteum (yellow body)
- The state of the empty follicle after ovulation
- secretes progesterone to maintain the endometrium
- A functional part of the menstrual cycle and maintenance of pregnancy
Corpus Albicans (white body)
- if fertilization DOESN’T happen, the corpus luteum deteriorates into this
- progesterone levels fall off
- The endometrium degenerates and the period begins
Chorion
- an extraembryonic membrane that mimics luteinizing hormone
- if pregnancy occurs, the developing embryo produces hCG from this membrane
- stimulates the corpus luteum to produce progesterone
Ectopic Pregnancy
When the developing embryo implants outside and not inside te uterus. The most common site for this the Fallopian tube (tubal pregnancy)
Dystocia
Painful labor
*Pain reduction: epidural injected into epidural space which numbs nerves
