male reproductive system

Question 1

what is the inguinal region?

Answer 1

• The groin; junction between anterior abdominal wall and thigh
• Inguinal canal 2.5-4cm long originates from deep to abdominal wall
• Passes infero-medially towards genitalia
• Natural weak point in abdominal wall; inguinal hernia

Question 2

what is the inguinal canal formed between?

Answer 2

• Anterior: external oblique muscle/fascia
• Posterior: internal oblique muscle/fascia
• Superior: transversus abdominus muscle
• Inferior: inguinal ligament

Question 3

what does the inguinal canal contain?

Answer 3

• Spermatic cord structures (male) / round ligament and genital nerve

(female)

• Inguinal nerve

Question 4

what is the deep ring and superficial ring regarding the inguinal canal?

Answer 4

deep ring:
- midway between ASIS and symphysis pubis, lateral to inferior epigastric vessels
- beginning of tubular evagination (‘pouch’) of abdominal wall transversalis fascia covering internal canal structures (internal spermatic fascia)

superficial ring:
- distal end, superficial to pubic tubercle
- Triangular opening through external oblique muscle
- Tubular evagination of external oblique fascia (external spermatic fascia)

Question 5

what is an inguinal hernia and what are the 2 classifications?

Answer 5

• Protrusion of sac of peritoneum into the inguinal canal
• May contain omental fat or potentially bowel loops

classifications:
-Indirect
-Direct

Question 6

indirect inguinal hernia

Answer 6

• through the deep inguinal ring (lateral to inferior epigastric

vessels)

• More common (especially in men)
• Result of processus vaginalis remaining open (congenital)

Question 7

Direct inguinal hernia

Answer 7

• Through weakness of posterior inguinal wall
• Medial to inferior epigastric vessels
• More common in older men; acquired due to weakness

Complications include bowel obstruction and potential strangulation and necrosis.

Question 8

what are the functions of the male reproductive system? what organs are involved?

Answer 8

• Production, maturation, and storage of sperm
• Delivery of sperm into the female reproductive system
• Excretion of urine

organs-
gonads (testes), ducts, accessory sex glands, penis.

Question 9

what are the functions of the organs of the male reproductive system

Answer 9

• Gonads - Testes: produce sperm and testosterone
• Ducts: transport, store, and mature sperm
• Accessory sex glands: secrete liquid portion of semen
• Supporting structures -Penis: passage for excretion of urine and ejaculation of sperm

Question 10

what are the main structures of the male reproductive system?

Answer 10

• scrotum
• testes
• ducts:

-ductus deferens, ejaculatory ducts, urethra

• accessory sex glands:
  -Seminal vesicles, prostate gland, bulnourethral glands
• penis

Question 11

what is the scrotum and what describe its features externally and internally

Answer 11

• Pouch / sack supporting testes- (literally means bag)

Externally:

• Loose skin, superficial fascia and smooth muscle separate by median ridge - raphe
• Attached to root of penis

Internally:

• Septum divides into two sacs with a testis
• Fascia/dartos muscle

Question 12

what are the testes?

Answer 12

• Paired oval glands
• Covered by white fibrous capsule that extends inwards to create internal compartments – 200-300 lobules
• Each lobule contains 1-3 coiled seminiferous tubules
• Seminiferous tubules -lined with spermatogenic cells

Question 13

what is the role of the testes?

Answer 13

• Against the basement membrane of the tubules are spermatogonia
• Towards the lumen are layers of cells in advancing maturity, once mature they are released into the lumen
• Between the sperm cells are sustentacular cells (Sertoli)
• protect and nourish spermatogenic cells, phagocytize degenerative cells, secret fluid and release the hormone inhibin
• Between the tubules are interstitial cells (Leydig) – secrete testosterone.

Question 14

what are the ducts of the male reproductive system?

Answer 14

• eminiferous tubules
• Epididymis
• Ductus (vas) Deferens
• Ejaculatory ducts
• Urethra

Question 15

what are the ducts of the testes

Answer 15

• Continual release of sperm into the lumen of seminiferous tubules, and fluid secreted by the sustentacular cells propels them along the ducts
• Travel through convoluted seminiferous tubules to straight tubules distally and into a network of ducts called the rete testis
• Move then through efferent ducts into epididymis

Question 16

what is the epididymis?

Answer 16

• Comma-shaped organ on posterior border ofeach testis
• Efferent ducts join epididymis superiorly at head
• Continue as tightly coiled ductus epididymis to form main body
• Smaller distal tail continues as ductus (vas)deferens

Question 17

what is the ductus epididymis

Answer 17

• 6m long if laid out (<4cm in length when coiled), 1mm diameter
• Site of sperm storage and maturation (up to a month)
• Helps propel the sperm during arousal by peristaltic contraction of the smooth muscle into the ductus (vas) deferens

Question 18

ductus deferens

Answer 18

• Distal to tail of epididymis on inferior aspect of testis
• Larger diameter, straighter

Question 19

what is the long course of ductus defers

Answer 19

• Superiorly along posterior aspect of epididymis and penetrates the inguinal canal
• Supero-medially along inguinal canal (part of spermatic cord)
• Through deep inguinal ring and into pelvic cavity,
• Over ureter, and inferiorly along posterior aspect of bladder
• Dilated most distally at ampulla where joins ejaculatory ducts

Question 20

what are the ejaculatory ducts

Answer 20

• Formed at junction between ampulla of vas deferens and duct from seminal vesicles
• Short - Approximately 2cm long
• Pass from superior to prostate, inferiorly and anteriorly through prostate
• Terminate into prostatic portion of urethra
• Release sperm and secretions from seminal vesicles into the urethra prior to ejaculation

Question 21

what is the urethra

Answer 21

• The terminal duct
• Conveys both sperm and urine

Passes through:

• inferior portion of the prostate,
• deep muscles of the perineum

-opening is called the external urethral orifice.

Question 22

what is spermatogenesis

Answer 22

Sperm production – involves Mitosis and Meiosis

Question 23

mitosis of spermatogonium- somatic cell division

Answer 23

• Stem cell (46 pairs of chromosomes) – divides into two daughter cells (23 pairs of chromosomes)
• Diploid cells – one stays a stem cell, one enters meiosis called primary spermatocyte

Question 24

meiosis- two cycles of division

Answer 24

• At then end of Meiosis I cells now 2 secondary spermatocytes (23 chromosomes and a pair of
  duplicate chromatids)
• Meiosis II produces 4 haploid spematids – each have 23
  individual chromosomes (one from each pair)

Question 25

what is the last step of spermatogenesis

Answer 25

v- Last step of Spermatogenesis – each spermatid matures into a spermatozoon (sperm) with a flagellum (tail) - Takes about 5 weeks to complete

Question 26

what is the role of semen in regulating the male reproductive systems

Answer 26

- mixture of sperm and semen -typical ejaculation 2-5ml containing between 50-150 million sperm per ml -acidic prostate secretion and alkaline overall pH 7.2 - 7.7; helps neutralise acid in urethra and vagina. -provides medium to transport and give nutrients to sperm -contains antibacterial agent to kill bacteria -Coagulates initially but then re-liquifies due to enzymes from prostate to allow movement of sperm.

Question 27

what are the accessory sex glands

Answer 27

- seminal vesicles - prostate - bulbourethral glands

Question 28

what are the seminal vessels, and what do they secrete?

Answer 28

- Paired pouch-like structures, convoluted - 5cm long - Posterior/base of urinary bladder, anterior to the rectum - Secrete viscous/sticky fluid 60% semen volume * Alkaline – neutralise acids harmful to sperm * Rich in fructose - ATP production by sperm * Prostaglandins - sperm viability/motility - Fluid passed into ejaculatory duct

Question 29

some features of the prostate

Answer 29

- Doughnut shaped – size of a golf ball - Lies inferior to bladder, surrounds prostatic urethra - Grows slowly until puberty, then rapidly until around 30 - Typically grows again from age of 45 - Produces milky slightly acidic fluid (around 25% semen volume) which aids sperm motility and viability * Citric acid; ATP production * Acid phosphatase * Proteolytic enzymes (regulated by testosterone): -Prostate-specific antigen (PSA); liquefies semen dissolves cervical mucous - Pepsinogen, amylase, lysozyme, hyaluronidase - Enters urethra through numerous prostatic ducts

Question 30

what is the bulbourethral glands?

Answer 30

- Also known as Cowper’s glands - Paired pea-sized organs - Inferior to prostate, within urogenital diaphragm either side of the urethra - Ducts open onto spongy urethra in root of penis

Question 31

what fluid does the bulb-urethral gland produce and why?

Answer 31

Produces fluids during arousal to protect sperm: * alkaline substance to neutralise acids in urethra and vagina * mucous to lubricate tip of penis an urethra

Question 32

what is the penis and its main components

Answer 32

- Contains urethra as passageway for urine and semen - Method to deliver semen - Consists of: - ***Body*** - ***Root*** - ***Glans*** - Supported by two ligaments continuous with fascia of penis: - ***Fundiform ligament***; inferior part of linea alba - ***Suspensory ligament of penis***; from pubic

Question 33

what is the structure and the body of the penis

Answer 33

- Three cylindrical masses, each surrounded by fibrous ***tunica albuginea*** - Consists of tissue permeated with sinuses for blood - Paired ***corpus cavernosum*** (hollow body) on dorsal surface - Penetrated by deep arteries of penis - Smaller ***corpus spongiosum*** on ventral and midline surface - Contains spongy urethra, keeps patent during ejaculation