Reproductive Systems 04 Oct 2024
Learning Objectives
1. ID male and female gametes
a. state the purpose of meiosis
2. Name accessory organs and gonads of male reproductive system
a. and cite the fxns
3. Describe the composition and function of semen
4. draw and label spermatozoon
5. ID the two hormones that regulate production and development of male gametes
6. explain how testosterone production is regulated
a. list its effects
7. Discuss 3 types of male reproductive system disorders and examples
8. name the accessory organs and gonads of the female reproductive system
a. cite fxns
9. Describe changes during the course of the menstrual cycle w/ regard to hormone production,
the ovary, and the uterus
10.describe the changes that occur during and after menopause
11.discuss 3 types of female reproductive system disorders and examples
12.Cite the main methods of birth control use
Male RepSys Anatomy and Fxn
fxn: manufacture spermatozoa (sperm cells) and to deliver them to the female
contains: 2 testes (sites of spermatozoa production; deliver to epididymis) and the accessory organs
Accessory Organs
epididymis—coiled tube on the surface of the testis in which sperm cells are stored and in
which they mature
o extends upward as the ductus deferens
ductus deferens (“vas deferens”)—tube that carries sperm cells from the testis to the urethra
o widens to form an ampulla before it joins with the duct of the seminal vesicle
ampulla—saccular dilation of a canal or duct
seminal vesicle—gland that contributes secretions to the semen
ejaculatory duct—joined vas deferens and seminal vesicle; travels through the prostate gland
and then empties into the urethra
Semen (“seed”)
semen—mixture of sperm cells and secretions from several glands of the male rep. tract;
alkaline
, o fxn:
nourish the spermatozoa
transport the spermatozoa
neutralize the acidity of the male urethra and female vaginal tract
lubricate the rep. tract during sexual intercourse
prevent infection by means of antibacterial enzymes and antibodies
Glands that contribute secretions to semen
The Seminal Vesicles
twisted muscular tubes with many small outpouchings
fxn: provides nourishment; has simple sugars; makes up large part of semen’s volume
The Prostate Gland
gland that surrounds the urethra below the bladder in males and contributes secretion to
semen; interior to urinary bladder
fxn:
o alkaline secretion neutralizes vaginal acidity and enhances spermatozoa’s motility
o ducts carry secretion into urethra
o muscle contracts to expel semen from the body
Bulbourethral Glands (Cowper gland)
fxn: secretes mucus to lubricate the urethra and tip of penis during sexual stimulation
loc: pelvic floor, inferior to prostate gland
o empties into urethra
Urethra and Penis
Penis—spongy tissue
3 segments each called a corpus: 1 corpus spongiosum (contains the urethra), 2 corpora
cavernosa
glans—enlarged distal portion of the penis
prepuce—foreskin
erection—fxn: makes semen ejection possible
ejaculation—forceful ejaculation of semen thru urethra; initiated by reflex centers in spinal
cord that stimulate smoot muscle contraction in the prostate AND contraction of skeletal
muscle in pelvic floor
o involuntary sphincter at base of bladder closes to prevent release of urine
o sperm lives for a maximum of 5-7 days
The Testes—outside the body proper; inside scrotum
male external genitalia—the penis and scrotum
Scrotum—sac in which the testes are suspended
o inguinal canal—in abdominal wall thru which each testis normally descends into the
scrotum
, o spermatic cord—extends thru the inguinal canal and suspends the testis; contains
blood vessels, nerves and ductus deferens
o must descend completely and be at the temperature of the scrotum (several degrees
lower than abdominal cavity
Internal Structure
seminiferous tubules—tubules in which sperm cells develop in the testis
sustentacular cells— (“Sertoli cells”) cells in the seminiferous tubules that aid in the
development of sperm
specialized testicular interstitial cells— (“Leydig cells”) secrete testosterone
testosterone—male sex hormone produced in the testes; promotes sperm cell development
and maintains secondary sex characteristics
The Spermatozoa
manufactured continuously in the seminiferous tubules beginning at puberty
spermatozoon—a mature male gamete with an oval head that is mostly a nucleus containing
chromosomes, a middle, and tail
o acrosome—cap-like structure over the head of the sperm cell that contains enzymes
that helps the sperm penetrate the ovum
o flagellum propels the sperm through the female reproductive tract to the ovum
o middle region (midpiece) contains many mitochondria that provide energy for
movement
Hormonal control of Male Reproduction
gonadotropins—protein hormones produced by anterior pituitary
o FSH—stimulates the sustentacular cells to produce growth factors that promote the
formation of spermatozoa
o LH—stimulates the interstitial cells to produce testosterone needed for sperm cell
development
o GnRH—hormone secreted by hypothalamus starting at puberty that triggers release of
FSH and LH; continuously secreted in adult males
Testosterone—circulating testosterone is kept constant thru negative
feedback mechanism
o as testosterone increase, hypothalamus secretes less GnRH
o as testosterone decreases, hypothalamus secretes more GnRH
Testosterone—stimulates formation and development of spermatozoa
o diffuses into surrounding fluids and absorbed into bloodstream
o fxns
development and maintenance of male rep accessory organs
dev. of spermatozoa
dev. of secondary sex characteristics, traits that characterize males and females
but are not directly concerned with reproduction
deeper voice
broader shoulders
narrower hips
a greater percentage of muscle tissue
Learning Objectives
1. ID male and female gametes
a. state the purpose of meiosis
2. Name accessory organs and gonads of male reproductive system
a. and cite the fxns
3. Describe the composition and function of semen
4. draw and label spermatozoon
5. ID the two hormones that regulate production and development of male gametes
6. explain how testosterone production is regulated
a. list its effects
7. Discuss 3 types of male reproductive system disorders and examples
8. name the accessory organs and gonads of the female reproductive system
a. cite fxns
9. Describe changes during the course of the menstrual cycle w/ regard to hormone production,
the ovary, and the uterus
10.describe the changes that occur during and after menopause
11.discuss 3 types of female reproductive system disorders and examples
12.Cite the main methods of birth control use
Male RepSys Anatomy and Fxn
fxn: manufacture spermatozoa (sperm cells) and to deliver them to the female
contains: 2 testes (sites of spermatozoa production; deliver to epididymis) and the accessory organs
Accessory Organs
epididymis—coiled tube on the surface of the testis in which sperm cells are stored and in
which they mature
o extends upward as the ductus deferens
ductus deferens (“vas deferens”)—tube that carries sperm cells from the testis to the urethra
o widens to form an ampulla before it joins with the duct of the seminal vesicle
ampulla—saccular dilation of a canal or duct
seminal vesicle—gland that contributes secretions to the semen
ejaculatory duct—joined vas deferens and seminal vesicle; travels through the prostate gland
and then empties into the urethra
Semen (“seed”)
semen—mixture of sperm cells and secretions from several glands of the male rep. tract;
alkaline
, o fxn:
nourish the spermatozoa
transport the spermatozoa
neutralize the acidity of the male urethra and female vaginal tract
lubricate the rep. tract during sexual intercourse
prevent infection by means of antibacterial enzymes and antibodies
Glands that contribute secretions to semen
The Seminal Vesicles
twisted muscular tubes with many small outpouchings
fxn: provides nourishment; has simple sugars; makes up large part of semen’s volume
The Prostate Gland
gland that surrounds the urethra below the bladder in males and contributes secretion to
semen; interior to urinary bladder
fxn:
o alkaline secretion neutralizes vaginal acidity and enhances spermatozoa’s motility
o ducts carry secretion into urethra
o muscle contracts to expel semen from the body
Bulbourethral Glands (Cowper gland)
fxn: secretes mucus to lubricate the urethra and tip of penis during sexual stimulation
loc: pelvic floor, inferior to prostate gland
o empties into urethra
Urethra and Penis
Penis—spongy tissue
3 segments each called a corpus: 1 corpus spongiosum (contains the urethra), 2 corpora
cavernosa
glans—enlarged distal portion of the penis
prepuce—foreskin
erection—fxn: makes semen ejection possible
ejaculation—forceful ejaculation of semen thru urethra; initiated by reflex centers in spinal
cord that stimulate smoot muscle contraction in the prostate AND contraction of skeletal
muscle in pelvic floor
o involuntary sphincter at base of bladder closes to prevent release of urine
o sperm lives for a maximum of 5-7 days
The Testes—outside the body proper; inside scrotum
male external genitalia—the penis and scrotum
Scrotum—sac in which the testes are suspended
o inguinal canal—in abdominal wall thru which each testis normally descends into the
scrotum
, o spermatic cord—extends thru the inguinal canal and suspends the testis; contains
blood vessels, nerves and ductus deferens
o must descend completely and be at the temperature of the scrotum (several degrees
lower than abdominal cavity
Internal Structure
seminiferous tubules—tubules in which sperm cells develop in the testis
sustentacular cells— (“Sertoli cells”) cells in the seminiferous tubules that aid in the
development of sperm
specialized testicular interstitial cells— (“Leydig cells”) secrete testosterone
testosterone—male sex hormone produced in the testes; promotes sperm cell development
and maintains secondary sex characteristics
The Spermatozoa
manufactured continuously in the seminiferous tubules beginning at puberty
spermatozoon—a mature male gamete with an oval head that is mostly a nucleus containing
chromosomes, a middle, and tail
o acrosome—cap-like structure over the head of the sperm cell that contains enzymes
that helps the sperm penetrate the ovum
o flagellum propels the sperm through the female reproductive tract to the ovum
o middle region (midpiece) contains many mitochondria that provide energy for
movement
Hormonal control of Male Reproduction
gonadotropins—protein hormones produced by anterior pituitary
o FSH—stimulates the sustentacular cells to produce growth factors that promote the
formation of spermatozoa
o LH—stimulates the interstitial cells to produce testosterone needed for sperm cell
development
o GnRH—hormone secreted by hypothalamus starting at puberty that triggers release of
FSH and LH; continuously secreted in adult males
Testosterone—circulating testosterone is kept constant thru negative
feedback mechanism
o as testosterone increase, hypothalamus secretes less GnRH
o as testosterone decreases, hypothalamus secretes more GnRH
Testosterone—stimulates formation and development of spermatozoa
o diffuses into surrounding fluids and absorbed into bloodstream
o fxns
development and maintenance of male rep accessory organs
dev. of spermatozoa
dev. of secondary sex characteristics, traits that characterize males and females
but are not directly concerned with reproduction
deeper voice
broader shoulders
narrower hips
a greater percentage of muscle tissue
