Exam 7 - Oz Male First 63 cards Flashcards
Production of offspring by making germ cells called gametes
Sexual Reproduction
Male gamete (sperm cell) unites with female gamete (secondary oocyte)
Fertilization
This produces one cell containing one set of chromosomes from each parent
Fertilization
Male gamete (sperm cell) unites with female gamete (secondary oocyte)
Produce gametes and secrete sex hormones
Gonads
Store and transport gametes
Ducts
Produce substances to protect the gamete and facilitate their movement
Accessory Sex Glands
Supporting Structures
Penis and Uterus assist delivery of ____
Uterus provides site for growth of….
gametes
…embryo and fetus
Gynecology
Branch of medicine concerned with the diagnosis and treatment of diseases of the female reproductive system
Study of the urinary system
Urologists also diagnose and treat diseases and disorders of male reproductive system
Urology
Andrology
Branch of medicine concerned with male disorders to include infertility and sexual dysfunction
- produce sperm and secrete hormones
Testes
- transports and stores sperm, assists in their maturation, conveys them to the exterior
Ducts
Epididymis
Ductus deferens (Vas deferens)
Ejaculatory ducts
Urethra
Ducts
Ductus deferens AKA
(Vas deferens)
- provides secretions to semen
- –Seminal vesicles
- –Prostate
- –Bulbourethral glands
Accessory Sex Glands
- supports the testes
- delivers sperm into the female reproductive tract
Supporting Structures
Scrotum
Penis
Devoid of fat
Numerous sebaceous and sweat glands
Loose skin
Externally, the skin of the scrotum is one single pouch
Raphe (external ridge, fold of tissue, not a true septum)
Extends from urethral meatus, down the ventral shaft, scrotum and ends at the anus
Represents the fusion of the genital tubercles (embryonic development)
(external ridge, fold of tissue, not a true septum)
Raphe
Scrotum
Raphe
Extends from ____, down the ventral shaft, scrotum and ends at the anus
urethral meatus
Scrotum
Raphe
Represents the fusion of the…
…genital tubercles (embryonic development)
Scrotum:
- Skin
- Subcutaneous layer (derived from abdominal structures during embryonic development)
True
(derived from abdominal structures during embryonic development)
Subcutaneous layer
Subcutaneous layer
Dartos muscle (smooth muscle)
External spermatic fascia
Cremaster muscle (skeletal muscle)
Internal spermatic fascia
Tunica vaginalis (parietal layer)
Tunica vaginalis (visceral layer)
Dartos muscle (type?)
(smooth muscle)
Cremaster muscle (type?)
(skeletal muscle)
Tunica vaginalis (type?)
(parietal layer)
Tunica vaginalis (two types of layers)
(parietal layer)
(visceral layer)
slide 17… great pic of the scrotum layers
take a look at that sweet meat
Scrotum
Internally divided into two sacs by
Each sac contains…
scrotal septum
…single testis
SLIDE 18
Regulation of temperature of the testes
Normal sperm production requires temperatures….
Lower temperature maintained in the scrotum because it is…
….slightly below core body temperature
….outside the pelvic cavity
Muscles contract in colder temperatures to preserve heat
What is cremaster?
How about dartos?
Cremaster- contraction moves testes closer to body to absorb more heat
Dartos- causes scrotum to become tighter (more wrinkled) which reduces heat loss
**Exposure to warmth reverses this process
check out slide 20 to see the cremaster and dartos contracted vs relaxed
if you’re into that sort of thing
Testis- singular
Testes/testicles- plural
Paired oval glands
Measure about 2 inches long and 1 inch in diameter
Develop near the…. and then do what in 7th month of fetal development?
kidneys, descend through the inguinal canal in the 7th month of fetal development
Considered part of the scrotum as well as part of the testicles
Tunica vaginalis
Inner most layer of the scrotum
Outer most layer of the testicle
Tunica vaginalis
Considered part of the scrotum as well as part of the testicles
Forms from the peritoneum during descent of testes?
Tunica vaginalis:
Parietal layer
Visceral layer
Cavity formed between the two layers which holds small amount of lubricating fluid
Tunica vaginalis
If you place a flashlight directly on the skin, it will shine through if it’s fluid filled
If it does not shine through, its likely solid
Transillumination
Internal to the tunica vaginalis layer
White fibrous dense tissue
Extends inward to form septa that divide the testis into lobules
—Think of a hard boiled egg
Tunica albuginea
Functional unit of the testicles
Each testis contains 200-300
Made up of seminiferous tubules (1-3 in each lobule)
Lobules
slide 25 has a sweet picture
nuts
Seminiferous Tubules
Contain two types of cells?
Spermatogenic cells- sperm forming cells
Sertoli (sustentacular) cells- supports spermatogenesis
- sperm forming cells
Spermatogenic cells
- supports spermatogenesis
Sertoli (sustentacular) cells
Location of spermatogenesis
Begins with primordial germ cells during fetal development which then differentiate into…
Spermatogonia
Seminiferous Tubules
Enter the testes during 5th week of embryonic development
These remain dormant until puberty and then when activated, aid in production of sperm
Spermatogonia
Seminiferous Tubules
In order of advancing maturity (young to old)
Spermatogonia - Primary spermatocyte - Secondary spermatocyte - Spermatid - Sperm cell (spermatozoa)
Seminiferous Tubules:
Sertoli cells AKA
(sustentacular cells)
Embedded amongst the spermatogenic cells
Extend from the basement membrane to lumen of tubule
Support and protect spermatogenic cells
Sertoli cells (sustentacular cells)
Nourish spermatocytes, spermatids, sperm
Phagocytize excess spermatid cytoplasm
Controls release of sperm into lumen
Produces fluid for sperm transport INSIDE the tubules
Produces androgen binding protein (ABG) which has effects of testosterone
Sertoli cells (sustentacular cells)
Sertoli cells (sustentacular cells)
How do they Support and protect spermatogenic cells?
Nourish spermatocytes, spermatids, sperm
Phagocytize excess spermatid cytoplasm
Controls release of sperm into lumen
Produces fluid for sperm transport INSIDE the tubules
Produces androgen binding protein (ABG) which has effects of testosterone
Seminiferous Tubules:
Tight junctions formed by Sertoli cells
Isolates developing gametes from blood
Blood-Testis barrier
Seminiferous Tubules:
Prevents an immune response to spermatogenic cell’s surface antigens
These antigens are recognized as “foreign” by the immune system
Blood-Testis barrier:
Tight junctions formed by Sertoli cells
Isolates developing gametes from blood
Seminiferous Tubules:
Located in the tunica albuginea surrounding the seminiferous tubules
Produces and secretes testosterone
Leydig Cells
Produces and secretes testosterone
- –Development of masculine characteristics
- –Promotes male sex drive
Leydig Cells
Seminiferous Tubules
on slide 29 and 30
Seminiferous Tubules
on slide 29 / 30
Takes 65-75 days
Spermatogenesis
Contains diploid (2n) number of chromosomes (46)
Under the influence of testosterone, these undergo mitosis (at puberty)
Spermatogonia
Some spermatogonia remain near the basement membrane and act as reservoir of cells for future sperm production
Others lose contact with basement membrane, squeeze through blood-testis barrier and undergo development
Differentiate into primary spermatocytes
Spermatogonia:
Under the influence of testosterone, these undergo mitosis (at puberty)
Differentiate into primary spermatocytes
Spermatogonia
in Spermatogenesis
Contains diploid (2n) number of chromosomes (46)
Starts to replicate its own DNA
Meiosis 1 begins at this point
Primary Spermatocytes
of Spermatogenesis
Homologous pairs of chromosomes line up at metaphase plate where cross-over occurs
Meiotic spindle pulls one (duplicated) chromosome of each pair apart and pulls it to opposite poles of dividing cell
Two cells formed from Meiosis 1 called secondary spermatocytes
Primary Spermatocytes within spermatogenesis and the beginning of meiosis 1
Each cell is now haploid (n), contains 23 chromosomes
Each chromosome is made up of two chromatids (two copies of DNA) still attached by a centromere
Meiosis 2 occurs at this point
Secondary spermatocytes within Spermatogenesis
Meiosis 2 occurs at this point
Chromosomes line up at metaphase plate where the two chromatids of each chromosome separate
Four (4) haploid cells (23 chromosomes) are produced called spermatids
Secondary spermatocytes within Spermatogenesis
Spermatogenesis:
A single primary spermatocyte produces four spermatids via two rounds of cell division
meiosis 1 & 2
2n- Diploid- 46 chromosomes
2n- Diploid- 46 chromosomes
n- Haploid- 23 chromosomes
n- Haploid- 23 chromosomes
n- Haploid- 23 chromosomes
spermatogenesis
– Final stage of spermatogenesis
Spermiogenesis
Development of haploid spermatids into sperm
One spermatid develops into one sperm
Spherical spermatids start to elongate
Spermiogenesis – Final stage of spermatogenesis
An acrosome forms atop the nucleus
A flagellum develops
Mitochondria multiply
Sertoli cells dispose of excess cytoplasm (if any)
Spherical spermatids start to elongate within SPERMIOGENESIS
- sperm being released from their connection to Sertoli cells into the lumen
Spermiation
Sperm CANNOT swim at this point
Fluid from Sertoli cells help the sperm travel to the ducts of the testes
sperm pick on slide 36
36
Each day approximately 300 million sperm complete spermatogenesis
—–Once ejaculated, can last up to 48 hours in female reproductive tract
Sperm
Cap-like vesicle filled with enzymes that help the sperm penetrate the secondary oocyte
—Enzymes include hyaluronidase and proteases
Acrosome
Sperm
—Enzymes include hyaluronidase and proteases
Acrosome
Sperm:
Tail
Divided into 4 parts
Neck- contains centrioles
Middle piece- contains mitochondria (energy for movement)
Principal piece- longest portion of tail
End piece- terminal tapering piece of tail
Hormonal Control of Testes
Male Reproductive Cycle
At puberty, ____ increases
At puberty, GnRH increases
produces androgen binding protein?
seminiferous tubules but in particular the SERTOLI CELLS (SUSTENTACULAR CELLS)
produces androgen binding protein?
seminiferous tubules but in particular the SERTOLI CELLS (SUSTENTACULAR CELLS)
produces and secretes testosterone?
Leydig cells (still need ABG to keep it loca FROM HER IN LECTURE DOUBLE CHECKl)
At puberty, GnRH increases
This stimulates ___ to secrete what?
gonadotrophs (Ant. Pit.) to secrete luteinizing hormone (LH) and follicle stimulating hormone (FSH)
Stimulates leydig cells to produce/secrete testosterone
LH
Synthesized from cholesterol in the testes
testosterone produced by Leydig cells (stimulated by LH)
Makes testosterone lipid-soluble which allows diffusion out of leydig cells, through interstitial fluid and into
- –Blood
- –Seminiferous tubules
The cholesterol makes it lipid soluble (produced by leydig cels and stimulated by LH)
5-alpha-reductase can convert some testosterone (in external genitals and prostate) into another androgen called
DHT (dihydrotestosterone)
DHT (dihydrotestosterone)
Much more potent androgen
Thought to “spark” puberty in males
Thought to combine with testosterone to account for male sexual behavior/desire
Responsible for male external organs in fetal development
The diploid cells AKA ____ are differentiated during what process, and what is formed from them?
meiosis I occurs to diploid (2n) AKA primary spermatocytes to form
secondary spermatocytes… which are now called haploid (n)
Much more potent androgen
Thought to “spark” puberty in males
Thought to combine with testosterone to account for male sexual behavior/desire
Responsible for male external organs in fetal development
DHT (dihydrotestosterone)
Hormonal Control of Testes
Some testosterone gets sent into systemic circulation
The majority of testosterone stays in the testes to ____
This is only accomplished by….
promote spermatogenesis
….androgen binding protein (ABG) being present to keep testosterone in this location
ABG is made in the Sertoli Cells
ABG is made in the
Sertoli Cells
Acts indirectly to stimulate spermatogenesis
Works synergistically with testosterone to act on the
Sertoli cells to secrete Androgen-binding protein (ABP)
ABP binds to testosterone in the tubule lumen which keeps a high concentration of testosterone in the area
Testosterone stimulates the final steps of spermatogenesis
FSH
Testosterone stimulates the final steps of spermatogenesis
Once normal level of spermatogenesis occurs, Sertoli cells release small amounts of inhibin
Reduces the production of FSH
LH is very important in males
said in lecture… so pay attention to those slides
Effects of Testosterone and DHT
Prenatal development
Testosterone stimulates development…
of male reproductive system ducts and descent of testes
FSH plays a much larger role in?
females according to lecture
Effects of Testosterone and DHT
DHT stimulates development of
external genitals
Effects of Testosterone and DHT
Converted in the brain to _____, which is thought to help develop certain brain regions
estrogens
Effects of Testosterone and DHT
Male sexual characteristics
—-At puberty development and enlargement of male sex organs and masculine secondary sex characteristics
Traits that distinguish males and females, but do not play a role in reproduction
Include muscular/skeletal growth (wide shoulders, narrow hips,) facial and chest hair, thickening of skin, increased sebaceous gland secretion, enlargement of larynx (deeper voice)
Effects of Testosterone and DHT
Development of Sexual Function (3 mentioned)?
Contributes to male sexual behavior, spermatogenesis
Contributes to sex drive in BOTH males and females
Adrenal cortex in females is the main source of androgen production
in females is the main source of androgen production
Adrenal cortex
Effects of Testosterone and DHT
Stimulation of Anabolism:
Stimulates ____
Obvious in heavier muscle and bone mass in most males as compared to women
protein synthesis
Reproductive System Ducts
In Males
Ducts of the Testis?
Straight tubules
Rete testis
Efferent ducts
Ductus epididymis
Epididymis (1 per testis)
Ductus Deferens (Vas Deferens)
Pressure generated by fluid secreted by Sertoli cells pushes the sperm and fluid through seminiferous tubules and then into these
Straight tubules
Found at the hilum of the testicle
A network of ducts that bridge the straight tubules and efferent ducts
Rete testis
Coiled ducts in the epididymis
Leads to the ductus epididymis
Efferent ducts
Ducts of the Testis
A single convoluted tube connecting the efferent ducts and the ductus deferens (vas deferens)
Would measure approximately 20ft in length if uncoiled
Ductus epididymis
Ducts of the Testis
Contains mostly tightly coiled ductus epididymis
Comma shaped organ about 1.5in long
Lies at the posterior aspect of each testis
Site of sperm maturation
Helps propel sperm into ductus deferens during sexual arousal
Stores sperm for up to several months
Any stored sperm that is not ejaculated within it’s lifecycle is reabsorbed
Epididymis (1 per testis)
slide 47 shows some ducts of the testis
slide 47
Ductus (Vas) Deferens
slid 50
Ductus Deferens AKA
(Vas Deferens)
Known as ductus deferens at this point
Within the epididymis, the tubule becomes less convoluted and it’s diameter increases
Traverses through the spermatic cord, enters the pelvic cavity, loops over the ureter where it enters the bladder and runs down the posterior surface
Ductus Deferens (Vas Deferens)
Right side drains directly into the inferior vena cava
Left side drains into the left renal vein
Because of this difference, much more pathology is usually found on the left side
Pampiniform Plexus
Ascends anterior to the vas deferens on both sides
Tortuous network of veins that drains the scrotum and the testicles
Spermatic Cord
Supporting structure, ascends out of the scrotum
Consists of?
Ductus (vas) deferens Testicular artery Veins Carry testosterone into circulation (via pampiniform plexus) Lymphatic vessels Autonomic nerves Cremaster muscle
____ with the ilioinguinal nerve pass through the inguinal canal (passage into abdominal cavity)
Spermatic cord
Ascends anterior to the vas deferens on both sides
Tortuous network of veins that drains the scrotum and the testicles
Pampiniform Plexus
Spermatic Cord– Venous Drainage
____ side drains directly into the inferior vena cava
Right
Spermatic Cord– Venous Drainage
___ side drains into the left renal vein
Because of this difference, much more pathology is usually found on the left side
Left
Spermatic Cord– Venous Drainage
Ejaculatory Duct
Formed by the union of the…
seminal vesicle and the ampulla of the ductus (vas) deferens
Ejaculatory Duct
Terminates at the…
Ejects sperm and seminal vesicle secretions
…prostatic urethra
A shared terminal duct
- Reproductive system
- Urinary system
Male Urethra
Approximately 8 inches long (internal and external)
Male Urethra
Passes through the prostate, deep muscles of the perineum, and then the penis
Male Urethra
Male Urethra
Subdivided in three sections:
Prostatic urethra- 1 inch long
Membranous urethra- 0.5 inch long
Spongy (penile) urethra- 6-8 inches long
Ends at external urethral orifice
Male Urethra
Male Urethra ends at?
external urethral orifice
slide 56 male urethra
slide 56 male urethra
Accessory Sex Glands
in Males
Secretes most of the ___ portion of semen
Small portion of fluid comes from the …..
fluid
….seminiferous tubules with sperm (1% of fluid in semen)
Includes
Seminal vesicle secretion- 60% of fluid in semen
Prostatatic secretion- 25% of fluid in semen
Bulbourethral gland secretion- 14% of fluid in semen
Accessory Sex Glands
THIS SLIDE MAY HAVE DOWNLOADED INCORRECTLY…. LOOK IF THERE IS A DIFFERENT NAME OTHER THAN “ACCESSORY”
slide 59
slide 59
Paired set of convoluted pouch-like structures
Usually 2 inches in length
Seminal Vesicles
Seminal vesicle secretions
acidic or alkaline?
Alkaline
Helps to neutralize acidic environment of male urethra and female reproductive tract (these would kill sperm)
Seminal vesicle secretions
viscous or thin?
Viscous
Helps to keep semen in female reproductive tract longer to increase chances of fertilization
Seminal vesicle secretions contain
Fructose
used for ATP production by sperm
Prostaglandins
Contributes to sperm motility and viability
Thought to stimulate smooth muscle contraction within female reproductive tract (help move sperm towards ova)
Clotting proteins
Helps semen coagulate after ejaculation (helps semen stay in female reproductive tract longer)
Single, walnut/doughnut shaped gland
Approximate size of a golf ball
Inferior to bladder
Surrounds prostatic urethra
Grows slowly in size from birth to puberty
At puberty grows rapidly until age 30 then remains stable until age 45 when further enlargement may occur
Prostate
Prostate
location and surrounds?
Inferior to bladder
Surrounds prostatic urethra
Secretes prostatic fluid
Component of semen
Prostate
Milky fluid Slightly acidic (pH of 6.5)
Prostatic fluid
Prostatic fluid
contains?
1) Citric acid- used for ATP production
2) Proteolytic enzymes- help break down clotting factors in seminal vesicle fluid (PPHAL)
- -Prostate specific antigen
- -Pepsinogen
- -Hyaluronidase
- -Amylase
- -Lysozyme
3) Seminalplasmin- decrease number of bacteria in semen
citric acid in prostatic fluid for?
Citric acid- used for ATP production
Proteolytic enzymes in prostatic fluid for?
Proteolytic enzymes- help break down clotting factors in seminal vesicle fluid (PPHAL)
- -Prostate specific antigen
- -Pepsinogen
- -Hyaluronidase
- -Amylase
- -Lysozyme
Seminalplasmin in prostatic fluid for?
Seminalplasmin- decrease number of bacteria in semen
