Male Anatomy Quiz Flashcards
(49 cards)
1
Q
Sperm Transport
A
Seminiferous Tubules -> Rete Testis -> Vas Efferens -> Epididymis (Head->Body->Tail) -> Vas Deferens -> Urethra -> Female Tract
2
Q
Rat Sperm Head
A
Hooked at the top
3
Q
Cock Sperm Head
A
Long and pointed at the top
4
Q
Sigmoid Flexure
A
- present in species with a fibroelastic penis
- extends during erection
- species: bull, ram, and boar
5
Q
Bull Penis
A
- Has a sigmoid flexure (extra portion inside that extends during erection)
- Pendulous testicles
- Epididymis is vertical and normally oriented
- Fibroelastic penis
6
Q
Ram Penis
A
- similar to bull
- has a sigmoid flexure (extra portion inside that extends during erection)
- Pendulous Testicles
- Epididymis is vertical and normally oriented
- Fibroelastic penis
- also has a sigmoid flexure on the glans penis that “sprays” the ejaculate (less volume that is more concentrated)
7
Q
Boar Penis
A
- Non-pendulous testicles: vertically oriented and inverted (tail of the epididymis is on the top close to the boar’s tail)
- Corkscrew shaped glans penis to fit the corkscrew shaped cervix of the sow
- prominent bulbourethral glands
8
Q
Stallion Penis
A
- Vascular Penis (no sigmoid flexure)
- Non-pendulous testicles (horizontal in orientation)
9
Q
Scrotum
A
- Two-lobed pouch that houses the testes
- Physical barrier to the environment
- Temperature regulation (MOST IMPORTANT** essential to spermatogenesis)
- Movement
- Concentric layers consisting of:
- Skin
- Tunica Dartos muscle
- Fascia
- Tunica Vaginalis
10
Q
Spermatic Cord
A
- houses lymphatics, vasculature, nerves, and the cremaster muscle
* vasculature plays an essential role in heat exchange
11
Q
Testes
A
- male gonads
- function to produce male gametes (spermatozoa
- produce male hormones (androgens *testosterone)
- also involved in libido, male characteristics, and sperm production
12
Q
Testicular Descent
A
- Important for proper development of spermatozoa and for temperature control
- Occurs late in gestation
- Steps:
1) fusion of the peritoneum and gubernaculum
2) rapid growth of the gubernaculum in the scrotum is the “force” that moves the testes into the inguinal canal
3) regression (shrinking) of the gubernaculum then pulls the testes deeper into the scrotum
13
Q
Cryptorchidism
A
- failure of one or both of the testes to descend into the scrotum (heritable trait)
14
Q
Unilateral Cryptorchidism
A
- one testis does not descend into the scrotum
- the one that descends is fertile, however, reduced sperm concentrations usually result
15
Q
Bilateral Cryptorchidism
A
- neither testis descend into the scrotum
- results in sterility due to the elevated temperature
16
Q
How much cooler should the testes be than the body?
A
4-6 degrees Celsius
17
Q
What type of situations elicit a response from the cremaster muscle to draw the testes up?
A
Fight or flight
18
Q
Pampiniform plexus
A
- counter current heat exchange between artery (~39C) and veins (~33C)
19
Q
Tunica dartos
A
- smooth muscle layer that is able to stay contracted for long periods of time (ex: colder temps)
20
Q
Sebaceous glands
A
- secrete oily substance
- evaporative cooling system
21
Q
Adipose tissue
A
- fat
- not extremely common
- may be seen in stallions used in show industry
22
Q
Methods of Temperature Regulation in the Testis
A
- pampiniform plexus
- tunica dartos
- sebaceous glands
- adipose tissue
23
Q
Epididymis
A
- highly convoluted duct attached to the tunica albuginea that functions in:
- sperm transport
- spermatozoa maturation
- concentrations of spermatozoa
- storage reservoir
24
Q
Three segments of the epididymis and what they do
A
- Head (Caput) : contains the efferent ducts, fluid reabsorption
- Body (Corpus) : maturation
- Cauda (Tail) : storage
25
Ampulla
- enlargements of the vas deferens into the pelvic urethra
* absent in boars
26
Vesicular glands
- produces a large portion of the ejaculate in bulls and rams
27
Prostate
- also known as the urethral glands
28
Bulbourethral glands
- produces the gel fraction
- very prominent in boar
29
What part of the penis is specialized in each species?
Glans penis (head of the penis)
30
Corpus Cavernosum
- majority of the interior penile shaft
- erectile tissue (smooth muscle)
31
Corpus Spongiosum
- surrounds urethra
- extends to gland
* very prominent in stallion (belling)
32
Retractor Penis Muscle
- has contracted and relaxed states
- when it is contracted the penis is retracted
33
Ischiocavernosus Muscle
- Inserts on crus penis
- Important for erection (compresses crus penis)
- presses down on penile veins
34
Urethralis Muscle
- striated muscle encapsulating the urethra
- responsible for movement of seminal plasma and sperm
- covers bulbourethral glands
35
Bulbospongiosus Muscle
- overlaps root of the penis
- covers bulbourethral glands
36
Fibroelastic Penis
- composed of fibrous elastic type tissue that extends in length to create an erection rather than in diameter like the vascular type penis
37
Vascular Penis
- composed of corpus cavernosum (dorsal) and corpus spongiosum (ventral) erectile tissues
- during an erection the corpus cavernosum and the corpus spongiosum fill with blood, causing the penis to become turgid/erect
38
Spermatogenesis
- formation of spermatozoa
* seminiferous tubules
* interstitial space
- requires hormones
- cell types
* Peritubular myoid -> Leydig -> Sertoli -> Spermatogonia -> Spermatocytes -> Spermatids -> Spermatozoa
39
FSH
- binds to Sertoli cells
40
LH
- binds to Leydig cells
41
Sertoli Cells
- help "govern" spermatogenesis
- located in the seminiferous tubule
- FSH binds to receptors on this cells type
42
Leydig Cells
- produce testosterone
- are located in the interstitial space
- LH binds to them
43
Peritubular Myoid Cells
- smooth muscle cells that aid in contraction
44
Sperm develop in the ____________ with direct interactions from the ____________.
seminiferous tubules ; Sertoli cells
45
What are the most immature cell type in the development of sperm?
Spermatogonia
46
What are the most mature cell type in the development of sperm?
round spermatid
47
What is the completion of spermatogenesis is marked by what?
the release of mature sperm into the lumen of the tubule termed "spermiation"
48
Anatomy of a spermatozoa from top to tail
1) Head: Acrosome -> apical ridge -> Equatorial segment
2) Neck
3) Mid-piece: outer dense fibers -> mitochondria
4) Principle piece: Myelin sheath
5) End piece
49
"Normal" shaped sperm decreasing in size
Bull -> Boar -> Ram -> Stallion
