L42: Comparative Penile Anatomy Flashcards
What is a penis?
Copulatory organ involved in both ejaculation and urination
What are the two penis types (according to structure)?
- Musculocavernous penis
- Fibroelastic penis
Which species have the musculocavernous penis?
Dog, horse, cat
Which species have the fibroelastic penis?
Bull, ram, buck, boar
Both types of penis have what 2 types of tissue?
- Fibroelastic
- Membranous (erectile)
The musculocavernous penis has an increase and a decrease of which tissues?
Increase % of Erectile & muscular tissue
Decrease % of fibroelastic tissue
The fibroelastic penis has an increase and a decreasae of what tissues?
Decrease % of Erectile & muscular tissue
Increase % of fibroelastic tissue
What are the muscles of the penis root? (4)
- Ischiourethralis
- Ischiocavernosus
- Bulbospongiosus
- Retractor penis
What is ischiocavernosus?
Erector of the penis
What is the bulbospongious innervated by? action?
Innervated: deep perineal nerve
Action: Contracts the urethra to expel remnants of urine or semen
What is the Retractor penis muscle innervate by? Action?
Innervated: Deep perineal nerve
Action: Retracts penis, notably action in fibroelastic penis
Where are the fibroelastic tissue and the membranous tissue present?
Fibroelastic: Tunica albuginea & trabeculae
Membranous: Erectile tissue
What structure contributes to tying during mating?
Bulbis glandis
Ovulation in the cat is induced by the stimulus of __?
Spikes
Penis is innervated by what nerve?
Pudendal nerve
What 3 structures are mainly supplying the blood to penis?
- Cavernous bodies
- Spongy body
- Bulbus glandis
What does erection result from?
Positive balance of blood flow- more blood accumulates in the penis as the venous drainage is interrupted
When an erection happens, which muscles are being constricted? (2)
- Ischiourethralis muscle
2. Vestibular bulb
While the musculocavernous penis erection is the result of __________, in the fibroelastic penis it is the result of the extension of the sigmoid flexure.
Extensive blood filling
In the musculocavernous penis, there is a ___ blood filling of cavernous and spongy bodies
Large
In the fibroelastic penis, there is a ___ blood filling of cavernous and spongy bodies- what else is there?
Reduced; extension of sigmoid flexure
In the bull and boar, glans morphology changes at the maximum stage of erection because of the _____ of penis
Spiraling
What is a prepuce?
Musculocutaneous shield that covers and protects the penis
What are the prepuce muscles of the bull? (2)
- Preputial cranialis (protractor)
2. Preputial caudalis (retractor)
What is the blood supply coming form for the prepuce? (2)
- External pudenal artery
2. “ vein
What is the innervation of prepuce? (3)
- Pudendal n
- Iliohypogastric n
- Ilioinguinal n
Where are the places of lymphatic drainage of penis and prepuce? (4)
- lumbar nodes
- internal iliac nodes
- deep inguinal node
- superficial inguinal node
