Reproductive System; Male Flashcards
Male and female reproductive system consist of
Gonads and Accessory Reproductive Organs
Gonads
(primary sex organs):testesin the male,ovariesin the female
Gonads Function
produce gametes (sex cells): sperm or oocytes 2) produce sex hormones
Accessory Reproductive Organs
include “ducts” that transport/store the gametes, glands that secrete substances for the gametes’ well-being, and the external genitalia
Accessory Reproductive Organs (2)
– the reproductive system is not fully functional until puberty
– at puberty, hypothalamus secretes hormones that tell Anterior Pituitary to release FSH (follicle stimulating hormone) and LH (luteinizing hormone), which act on ovaries and testes
– so you needFSH and LHto start gamete maturation and increased sex hormone production by the gonads
Testis Functions
1) to produce sperm
2) to produce androgens (male sex hormones)
* of the androgens, testosterone is the principal sex hormone
Testes External Anatomy
testes suspended in scrotum
Scrotum Function
to keep testes in a cooler external environment (3 degrees C cooler than internal body temp), to allow for normal sperm production
Spermatic Cord
runs from each testis into the abdomen
* contains blood vessels, nerves,and theductus (vans) deferens
Testis Internal Anatomy
– each testis divided into a series of internal compartments calledlobules
– each lobule contains up to 4seminiferous tubules (a tightly coiled structure, wheresperm are produced)
Testis - Within Seminiferous Tubules (1)
Spermatogonia: “stem cells” that help produce sperm
* these are the most immature male sex cells (This are on the outside of the tubule)
Testis - Within Seminiferous Tubules (2)
developing sperm (These are located more interiorly of the tubule, sperm develop from the outside edge toward the middle)
Testis - Within Seminiferous Tubules (3)
Sustentacular cells:these cells support, protect and nourish the developing sperm
Between Seminiferous Tubules
is someconnective tissue andinterstitial cells
*functionof these cells:produce and secrete androgens (specifically, testosterone)
Sperm Production
sex cells (gametes) created by MEIOSIS
* review your meiosis notes from exam 1 material!
* end result of meiosis: 4 cells produced, each w/23 chromosomes only!
First Step; Spermatogonia
- each contains 23 pairs of chromosomes (total: 46 chromosomes - diploid)
–divide by Mitosis and produceprimary spermatocytes
Second Step; Primary Spermatocytes
still 23 pairs of chromosomes (46 chromosomes - diploid)
* these cells divide by MEIOSIS * when they finish the 1st Meiotic Division, they form secondary spermatocytes
Third Step; Secondary Spermatocytes
contain 23 chromosomes only (haploid)
* they finish the 2nd Meiotic Division to produce spermatids (This is the end of Meiosis II)
Fourth Step; Spermatids
immature sperm - contain 23 chromosomes only (haploid)
*spermatids develop into sperm (spermatozoa)
Fifth Step; Sperm (Spermatozoa)
sperm will “shed” the cytoplasm from the spermatid, and develop:
1)head: contains DNA
* on head is an acrosome cap (Enzymes)
2)Midpiece (mitochondria)
3)tail (Flagellum)
Six Step: Release
sperm are then released from the sustentacular cell cytoplasm, and enter the lumen of seminiferous tubule
Regulation of the testes (1)
FSH from anteritor pituitary to sertoli cells on testes? – (Androgen-binding protein) facilitates sperm production; it is up to them to support this developing sperm
Regulation of the testes (2)
LH from anterior pituitary to interstitial cells – testosterone; LH encourages interstitial cells to produce testosterone
Spermatic Duct System - Epididymis
comma-shaped organ, located posterior to and on top of testis
* receive sperm from testis
Spermatic Duct System - Epididymis Function
1) it is the place where sperm mature (gain motility/mobility)
2) it stores sperm until ejaculated
Spermatic Duct System - Ductus (Vas) Deferens
18 inch long tube that runs from testis to prostate gland
Spermatic Duct System - Ductus (Vas) Deferens Travel Path
- part of its travel is within thespermatic cord
- then it enters the abdominopelvic cavity, winds around the bladder, and is
found near the prostate gland - ductus deferens will “merge” with the duct from seminal vesicle to form the Ejaculatory Duct
Spermatic Duct System - Ejaculatory Duct
each one will empty its contents into the urethra
* passes through the prostate gland (but does NOT include prostatic secretions)
How Sperm Develops, SEVEN UP (S)
Seminferous Tubules
How Sperm Develops, SEVEN UP (E)
Epidydimys
How Sperm Develops, SEVEN UP (V)
Vans Deferens
How Sperm Develops, SEVEN UP (2nd E)
Ejaculatory Duct
How Sperm Develops, SEVEN UP (N)
Nothing; This stands for literally nothing
How Sperm Develops, SEVEN UP (U)
Urethra
How Sperm Develops, SEVEN UP (P)
Penis
Accessory Reproductive Glands Function
to produce a nutritive, alkaline fluid (seminal fluid) to the sperm
sperm + seminal fluid =semen
Accessory Reproductive Glands Components
Seminal Vesicles
Prostate Gland
Bulbourethral Glands
Seminal Vesicles
(2) each lies on posterior wall of bladder
* each has a “duct” that merges with the ductus deferens, to form ejaculatory ducts
Prostate Gland
single, chestnut-shaped organ
- inferior to bladder
- contains the 1st part of the urethra (prostatic urethra) (This is where the prostate secretions would go)
Bulbourethral Glands
- each gland is pea-shaped
- lies within urogenital diaphragm(This helps control the urine, this is where the two tiny glands live and will secrete directly into the urethra)
Penis Functions
1) excrete urine
2) deliver sperm to female reproductive tract
Penis 3 Parts
Root
Body (Shaft)
Glans
Root
“fixed” end of penis
Body (Shaft)
moveable end
- 3 columns of erectile tissue:
- (2)corpora cavernosa: erectile tissue on top (dorsum) of penis
- (1) Corpus Spongiosum: erectile tissue underneathcorpora cavernosa, contains spongy (penile) urethra
Glans
enlarged tip of penishas corpus spongiosum only
* covered with prepuce (foreskin)
Erection
penis becomes “rigid”
- more blood flow to penis, erectile tissue become engorged with blood
- this is triggered by the parasympathetic nervous system (This is one of the few times where they actually work together and are not doing opposite things together)
Ejaculation
expulsion of semen from penis
* it is triggered by the Sympathetic Nervous System (Point and Shoe is a term for both of these)