Test 7 Reproductive Male Flashcards
What is the branch of medicine concerned w/diagnosis and treatment of diseases of the female reproductive system?
Gynecology
What is the branch of medicine that studies the urinary system and also diagnose and treat diseases and disorders of male reproductive system?
Urology
What is the branch of medicine concerned w/ male disorders to include infertility and sexual dysfunction?
Andrology
What are the transport and storage structures for sperm, assists in their maturation, and conveys them to the exterior?
DUCTS
- Epididymis
- Ductus deferens (Vas Deferens)
- Ejaculatory Ducts
- Urethra
What are considered the accessory sex glands in males and what are their function?
- Provides secretions to semen
- Seminal Vesicles
- Prostate
- Bulbourethral Glands
What are the supporting structures of the male reproductive system?
- Scrotum: Supports testes
- Penis: Delivers sperm into female reproductive tract
What structure of the male reproductive system consists of loose skin, Subcutaneous layer hands from the root of the penis and contains the Dartos muscle?
Scrotum
What type of muscle is the Dartos Muscle?
Smooth Muscle
The external scrotum appears as a single pouch, what is the median ridge that separates the scrotum into lateral portions called?
Raphe
The internal scrotum is divided into two sacs by what structure? What is contained in each?
Scrotal Septum
- Single Testis
- Subcutaneous Layer
- Dartos Muscle (Smooth Muscle)
What is the name of the muscle that surrounds each testis, consists of a series of bundles of skeletal muscle and descends as an extension of internal oblique muscle through the spermatic cord?
Cremaster Muscle
Production of sperm requires temperatures slightly lower than body temperature, What action will the Cremaster and Dartos muscle have in colder environments?
- Cremaster: Contraction moves testes closer to body to absorb heat
- Dartos: Scrotum becomes tighter (more wrinkled) reduce heat loss
The male gonads are also known as? Give plural and singular.
Testis: Singular
Testes/Testicles: Plural
The paired oval glands of the testes measure about 2in long by 1in diameter, weighing approx. 10-15gms, where do they develop and what occurs during the 7th months of fetal development?
- Develop: Near Kidneys
- Descend through the inguinal canal in 7th month of fetal development
Name the Testicular Anatomy from External to Internal?
-Scrotum
-Dartos Muscle
-External Spermatic Fascia
-Cremaster Muscle
-Internal Spermatic Fascia
-Tunica Vaginalis
(Parietal Layer)
(Visceral Layer)
-Tunica Albuginea
What portion of the testicular anatomy forms from the peritoneum during descent of testes and partially covers the testes?
Tunica Vaginalis
What portion of the testicular anatomy is internal to the tunica vaginalis, consists of a white fibrous capsule of dense irregular connective tissue, and extends inward to form septa that divide the testis into lobules?
Tunica Albuginea
How many Lobules are found with ea. testis and what is the name of the structure within ea. Lobule? How many are found in ea. Lobule?
- Lobule: 200-300
- In Lobule: Seminiferous Tubules
- 1-3 in ea. lobule
Where in the testis spermatogenesis occur?
Seminiferous Tubules
The Seminiferous Tubules contain what two cells and what are their roles in Spermatogenesis?
- Spermatogenic Cells: Sperm forming cells
- Sertoli (Sustentacular) Cells: Supports Spermatogenesis
What is the name of the stem cell that develops from the primordial germ cells?
Spermatogonial Stem Cell
The Spermatogonia cells enter the testes during what week of development and remain dormant until when?
- Primordial germ cells differentiate into Spermatogonial Stem Cell and enter testes during 5th week of development
- Dormant until puberty and then aid in production of sperm
Name the sequence by name of the maturity of a Sperm cell from young to mature?
- Spermatogonial Stem Cell
- Spermatogonium
- Primary Spermatocyte
- Secondary Spermatocyte
- Spermatid
- Sperm Cell (Spermatozoa)
The Sertoli Cells (Sustentacular Cells) are embedded amongst the spermatogenic cells and extend from basement membrane to lumen of tubul, what function do they serve?
- 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 tubules
- Secretes: Inhibin, Reg. effects Testosterone and FSH
Within the Seminiferous Tubules what is the tight junctions formed by Sertoli cells that isolates developing gametes from blood, called?
Blood-Testis Barrier
Why is it important to prevent Spermatogenic Cell’s from the blood?
- Surface Ag’s on spermatogenic cell’s cause an immune response
- Ag are recognized as “foreign”
What is the name of the cells that are located between the tubules and Secrete Testosterone?
Leydig Cells
The Secretion of Testosterone promotes what?
- Development of masculine characteristics
- Promotes male sex drive
What is the length of time for Spermatogenesis?
65-75 days
What is the name of the stem cell that contains diploid number of chromosomes and undergoes mitosis to differentiate into Primary Spermatocytes or remain near the basement membrane and act as a reservoir for future sperm production?
Spermatogonium
How many Chromosomes do Primary Spermatocytes contain and what is occurring during this stage of Spermatogenesis?
- Contain: 46 (2n) Chromosome
- Begin to replicate DNA
- Meiosis 1 Beings
Meiosis 1 of the Primary Spermatocytes during Spermatogenesis what is occurring?
- Homologous pairs of Chormosomes line up at Metaphase plate (Where cross-over occurs)
- Meiotic spindle pulls homologous pairs apart to opposite pole
- Two Cells formed
What are the Two cells formed from Meiosis 1 of Spermatogenesis in the Primary Spermatocytes called?
Secondary Spermatocytes
The Secondary Spermatocytes Contains how many Chromosomes? What is each Chromosome made up of?
Contains:
-Haploid (n), 23 Chromosomes
Chromosomes: = Two Chromatids attached by Centromere
What occurs within the Secondary Spermatocytes during Spermatogenesis?
Meiosis 2
- Chromosomes line up at Metaphase plate
- Chromatids separate
- Four Haploid cells (23 Chromosomes) produced
What are the four haploid cells created at the end of Meiosis 2 of the Secondary Spermatocytes during Spermatogenesis, called?
Spermatids
A single Primary Spermatocyte produces how many spermatids via what?
4
Via: Meiosis 1 and 2
What are the cell names during the Spermatogenesis process and how many Chromosomes do each contain? From beginning to end
- Spermatogonium (46)
- Primary Spermatocyte (46)
- Secondary Spermatocyte (23)
- Spermatids (23)
- Mature Sperm Cell (23)
What is the Final stage of spermatogenesis?
Spermiogenesis
What is occurring during Spermiogenesis?
-Spermatid into sperm
-No cell division
-Spermatid elongates
(Acrosome forms atop nucleus)
(Flagellum develops)
(Mitochondria multiply)
(Sertoli Cells dispose of excess cytoplasm)
-Spermiation
What is Spermiation?
Release of Sperm from connection of Sertoli Cells into the Lumen
What is significant of the fluid from the Sertoli Cells?
Help sperm travel to ducts of testes
-Sperm CANNOT swim at this point
Each day approximately how many sperm complete spermatogenesis?
300 Million
What is the Cap-like vesicle filled w/enzymes that help the sperm penetrate the secondary oocyte? What are the names of the enzymes?
Acrosome
- Enzymes:
- Hyaluronidase
- Proteases
What are the 4 parts of the tail of the Sperm and what is contained in each?
- Neck: Centrioles
- Middle Piece: Mitochondria (energy)
- Principal Piece: Longest portion
- End Piece: Terminal tapering piece
What increases at puberty stimulating Gonadotrophs (anterior pituitary) to secrete what hormones?
- Gonadotropin Releasing Hormone (GnRH)
- Luteinizing Hormone (LH)
- Follicle Stimulating Hormone (FSH)
What hormone stimulates leydig cells to secrete testosterone?
Luteinizing Hormone (LH)
Where and from what is Testosterone synthesized?
Synthesized from: Cholesterol
In: Testes
What is significant about Testosterone being synthesized from Cholesterol?
Lipid-soluble
-Allows diffusion out of Leydig cells, through interstitial fluid and into blood.
What enzyme is able to convert testosterone, in external genitals and prostate, into another androgen? What is the name of the androgen?
- Enzyme: 5-alpha-reductase
- Androgen: Dihydrotestosterone (DHT)
What hormone acts indirectly to stimulate spermatogenesis and works synergistically w/testosterone?
Follicle Stimulating Hormone (FSH)
FSH and Testosterone act on Sertoli cells to stimulate secretion of what hormone?
Androgen-Binding Protein (ABP)
What binds to testosterone in the tubule lumen in order to keep testosterone concentration high in the testis? What is the significance of this?
Androgen-Binding Protein (ABP)
-Significance: Testosterone stimulates final steps of Spermatogenesis
What is released to reduce production of FSH once normal levels of spermatogenesis occurs? What cell secretes this?
Inhibin Hormone
Secreted by Sertoli Cells
During Prenatal Development what effects does Testosterone and Dihydrotestosterone (DHT) have?
Testosterone:
-Stimulates development of male reproductive system ducts and descent of testes
-Converted to Estrogen in the brain for Brain development
Dihydrotestosterone:
-Stimulates development of external genitals
During Puberty what effects does Testosterone and Dihydrotestosterone (DHT) have?
-Development and Enlargement of male sex organs and masculine secondary sex characteristics
What are considered Secondary sex characteristics?
-Traits that distinguish males and female but do not play a role in reproduction
What are some of the secondary sex characteristics that development in males during puberty?
- Muscular/skeletal growth(Wide shoulder, narrow hips)
- Facial/chest hair
- Thickening of skin
- Increased sebaceous gland secretion
- Enlargement of larynx (deeper voice)
What supporting structures ascend out of the scrotum forming the Spermatic Cord (Consist of)?
- Ductus (vas) Deferens
- Testicular Artery
- Veins
- Lymphatic Vessels
- Autonomic Nerves
- Cremaster Muscle
What hormone does the veins of the Spermatic Cord carry into circulation? Via what structure is this accomplished?
Testosterone
Via: Pampniform Plexus
What structures pass through the inguinal canal for passage into the abdominal cavity?
- Spermatic Cord
- Ilioinguinal Nerve
When does Spermatogenesis begin in males and when does Oogenesis begin in females?
Male: Puberty
Female: Before Birth
What role/ contribution do the effects of Testosterone and DHT have on development of sexual function?
- Contribute to Male Sexual Behavior
- Contribute to Spermatogenesis
- Contributes to sex drive in BOTH male and female
What is the main source of Androgen production for females?
Adrenal Cortex
The effects of Testosterone and DHT is obvious in males due to heavier muscle and bone mass as compared to women, this is due to stimulation of what?
Anabolism
Stimulates Protein Synthesis
Testosterone levels are regulated by what kind of feedback?
Negative Feedback
Describe the sequence for the Negative Feedback of Testosterone?
1) Testosterone increases to certain level, Inhibits release of GnRH from Hypothalamus
2) Reduced GnRH= decreased stimulation for LH secretion from Anterior pituitary
3) Reduced plasma LH= decrease testosterone secretion from leydig cells in testes
4) Reduced Testosterone = reduced rate of spermatogenesis
Name the Ducts of the Testis?
1) Straight Tubules
2) Rete Testis
3) Efferent Ducts
4) Ductus Epididymis
5) Epididymis (Tightly coiled ductus epididymis)
6) Ductus Deferens (Vas Deferens)
The pressure generated by fluid secreted y Sertoli cells pushes sperm and fluid through the seminiferous tubules into what duct?
Straight Tubules
What is the network of ducts that bridge the Straight tubules and efferent ducts called?
Rete Testis
Sperm and Fluid travel from the Rete Testis to the coiled ducts in the epididymis, what is this structure called?
Efferent Ducts
The Efferent ducts lead to a single convoluted tube, that uncoiled would measure approx. 20ft in length, called what?
Ductus Epididymis
What structure contains tightly coiled ductus epididymis and lies at the posterior aspect of each testis?
Epididymis
What is the Shape, and function of the Epididymis?
Comma shaped organ
- Site of sperm maturation
- Helps propel sperm into ductus deferens during sexual arousal
- Stores sperm for up to several months
What will happen to stored sperm, in the epididymis, that is not ejaculated within it’s lifecycle?
Sperm are reabsorbed
What duct conveys sperm during sexual arousal from the epididymis toward the Ejaculatory ducts and ultimately the urethra?
Ductus Deferens (Vas Deferens)
At what point does the transition from the Ductus Epididymis to the ductus deferens occur?
- Tail of the Epididymis
- Ductus epididymis becomes less convoluted and diameter increases
The Ductus Deferens (Vas Deferens) are typically 18in long and travel what path to the urethra?
- Through Spermatic Cord
- Enters Pelvic cavity
- Loops over ureter and down posterior surface of the bladder
The terminal portion of the Ductus Deferens (Vas Deferens) widens into what?
The Ampulla
What other function do the Ductus Deferens have beside conveying sperm during sexual arousal?
Store sperm for several months
The Spermatic Cord travels through the Inguinal Canal, where does the inguinal canal originate and end? Approx how long is it?
-Originates: Deep (Abdominal) Inguinal Ring
(at aponeurosis of transversus abdominis muscle)
-Ends: Superficial (Subcutaneous) Inguinal Ring
(at aponeurosis of external oblique muscle)
-Approx. 2in in length
What is formed by the union of the seminal vesicle and the ampulla of the Ductus Deferens (Vas Deferens)?
Ejaculatory Ducts
The Ejaculatory Duct is approx. how long and terminates where? What is its function?
- Ea. duct is 1in in length
- Terminates at Prostatic Urethra
- Function: Eject Sperm and Seminal Vesicle Secretions
What is the name of the Shared terminal duct of the Reproductive system and urinary system, that is approx. 8 inches long, and passes, through the prostate, deep muscles of perineum, and then penis?
Male Urethra
What are the Subdivision of the Male Urethra and where does it end?
Three Subdivisions: -Prostatic urethra: 1in -Membranous Urethra: .5in -Spongy (penile) urethra: 6-8in Ends: External Urethral Orifice
The Accessory Sex Glands secrete most of the fluid portion of semen, small portion of fluid from seminiferous tubules w/sperm (1%), What are the Accessory Sex Glands?
- Seminal Vesicle Secretion: 60% of fluid
- Prostatic Secretion: 25% of fluid
- Bulbourethral gland secretion: 14% of fluid
What Accessory Sex Gland is a paired set of convoluted pouch-like structures 2 inches in length and secrete the majority of Seminal Fluid?
Seminal Vesicles
The Seminal Vesicle secretions are Alkaline and Viscous, what purpose do these serve?
- Alkaline: Neutralize acidic environment of male urethra and female reproductive tract
- Viscous: Keep semen in female reproductive tract longer to increase chance of fertilization
What is contained in the Seminal Vesicle Secretions?
-FRUCTOSE: Used for ATP production by Sperm
-PROSTAGLANDINS: Contributes to sperm motility and viability
Stimulate smooth muscle contraction w/in female reproductive tract (help move sperm toward ova)
-CLOTTING PROTEINS: Helps semen coagulate after ejaculation (help semen to remain in female reproductive tract longer)
What accessory sex gland is a single, walnut/doughnut shaped gland, approx. the size of a golf ball, surrounds prostatic urethra and lies inferior to the bladder?
Prostate
The Prostate is approx. 1.6in side-to-side, 1.2in top-to-bottom, and .8in front-to-back, at what time periods does the gland grow?
- Birth to Puberty (slow)
- Puberty to 30 (Rapid)
- 30-45 (Stable)
- 45+ may enlarge
Describe the Prostatic fluid and what does it contain?
-Milky Fluid
-Slightly Acidic (pH 6.5)
CONTAINS:
Citric Acid
Proteolytic Enzymes
Acid Phosphatase (unknown use)
Seminalplasmin
What is the Citric Acid and Seminalplasmins purpose within the prostatic fluid?
- Citric Acid: ATP Production
- Seminalplasmin: Decrease Bacteria in Semen
The Proteolytic Enzymes of Prostatic fluid, help break down clotting factors in seminal vesicular fluid, Name the enzymes?
Prostate Specific Ag Pepsinogen Lysozyme Amylase Hyaluronidase
What Accessory Sex Gland is a pea sized set, located inferior to the prostate on either side of membranous urethra, and open into the spongy urethra? What is this gland also known as?
Bulbourethral Glands (Cowper’s Glands)
What purpose do the Bulbourethral Glands (Cowper’s Glands)?
Secrete Alkaline Fluid and mucus in Urethra
- Protect Sperm from acidic urine
- Lubricates urethra and end of penis
- May Account for pre-ejaculate (no sperm)
The term Semen refers to what?
Mixture of sperm and seminal fluid (liquid of secretions from seminiferous tubules, seminal vesicles, prostate, and bulbourethral glands)
What is the typical volume during ejaculation? How many sperm will this contain?
2.5-5mL
-1mL contains 50-150 million sperm
(Only small fraction make it to secondary oocyte)
At what point is a male considered to be infertile?
20 million sperm per 1mL
What is the pH of Semen and what is its appearance?
-Alkaline- 7.2-7.7pH (Seminal vesicle lg volume of alkaline fluid compared to acidic prostate fluid)
Milky color (Prostatic fluid)
Sticky (Seminal Fluid and Bulbourethral Fluid)
Ejaculate will typically coagulate within what time frame and re-liquefies within what time frame? This is due to what?
- Coagulate: 5min due to clotting proteins from seminal vesicles
- Re-Liquefies: 10-20min due to Prostate Specific Ag and other enzymes
What may occur if there is abnormal or delayed liquefaction of clotted semen?
Partial or total immobilization of sperm
Unable to reach secondary oocyte
What is the term for the presence of blood in semen?
Hematospermia/
Hemospermia
What are some causes of Hematospermia (Hemospermia)?
- Inflammation of blood vessels lining seminal vesicles or other glands
- Trauma
- Prolonged Abstinence
- Excessive Masturbation
- Systemic Issues (HTN,etc…)
The Cylindrical shaped penis is divided into what sections?
Body
Glans Penis
Root
The Body is composed of three masses of tissue, each surrounded by fibrous tissue (Tunica Albuginea), what are they called?
- Corpora Cavernosa: 2 dorsolateral masses
- Corpus Spongiosum: Singular midventral mass, contains spongy urethra
The Corpora Cavernosa (2) and Corpus Spongiosum of the body of the penis is enclosed by what?
Skin and Subcutaneous Layers
Numerous blood sinuses lined by endothelial cells and surrounded by smooth muscle and elastic connective tissue
What is the Distal end of the corpus spongiosum, that slightly enlarges and is acorn shaped, called?
Glans Penis
What is the margin surrounding the base of the glans penis called?
Corona
The distal urethra enlarges, widens, and forms a slit-like opening called?
External Urethral Orifice
What is another name for the foreskin that covers the glans penis? What are some thoughts of the benefit of removing it?
Prepuce
Thought: Reduce UTI and protect against some STD if Circumcised
What portion of the penis contains the bulb (expanded posterior continuation of the base of corpus spongiosum) and contains the crura (two separated and tapered portions of corpora cavernosa)?
Root of the Penis
What encloses the bulb of the root of the penis? What does this aid in?
Bulbospongiosus Muscle
AIDS in: Ejaculation
What surrounds the Crura of the root of the penis?
Ischiocavernosus Muscle
The weight of the penis is supported by what structures and what are these continuous with?
Two Ligaments
Continuous w/fascia of the penis
What are the names of the ligaments that support the weight of the penis and where do they arise from?
- Fundiform Ligament: Inferior part of Linea Alba
- Suspensory Ligament: Pubic Symphysis
What nerves initiate and maintain an erection when sexual stimulation occurs?
Parasympathetic Fibers in Sacral Region of spinal cord
The Parasympathetic fibers in the sacral region of the spinal cord produce and release what? What does this cause?
Nitric Oxide (NO) -Causes: Smooth muscle in arteriole walls in erectile tissue to relax, allowing for dilation of both blood sinuses in corpora cavernosa and vessels
The increase in blood flow to the penis causes what to occur, in which this further helps maintain the erection?
Compresses Veins that drain the penis
What portion of the nervous system controls the release of semen during ejaculation?
Sympathetic Reflex (of Lumbar portion of Spinal Cord)
The Sympathetic Reflex causes what to constrict during ejaculation? In relation to the Bladder?
Smooth Muscle Sphincter at base of the bladder
What purpose does constricting the Smooth Muscle Sphincter at the base of the bladder serve?
Prevents:
Urine entering semen
Semen into Bladder
What occurs before ejaculation that propels semen into the spongy urethra and may lead to a small volume of emission?
Peristaltic contractions of epididymis, ductus deferens, seminal vesicles, ejaculatory ducts, and prostate propel semen into spongy urethra
What are the Muscles of the penis that contract when stimulated by which nerve during Ejaculation?
Bulbospongiosus
Ischiocavernosus
Superficial Transverse Perineus
NERVE: Pudendal Nerve
What occurs after ejaculation and stimulation has ended? (This will occur whether orgasm was achieved or interrupted)
-Arterioles Constrict
-Smooth Muscle Contracts
(Making Blood Sinuses Smaller)
-Relieves pressure on veins
(Allows blood to flow back out)
-Penis becomes flaccid
What is the term for a persistent and usually painful erection that does not involve sexual desire or excitement, can last for hours and can be accompanied by pain and tenderness?
Priapism
What are some causes of Priapism?
- Medications (Erectile dysfunction meds most common) (Trazodone: sleep med military uses)
- Spinal Cord Trauma
- Tumors
- Leukemia
- Sickle-Cell disease
