Male reproductive anatomy Flashcards
What is the channel of sperm to follow?
- testis - manufacturing
- epididymis body and head - membrane changes, nuclear and flagellar stabilization, motility, cytoplasmic droplet translocation
- epididymis tail - smooth muscle contraction from sexual stimulation
- accessory sex glands - metabolic substrates, surface coatings and transport for spermatozoa
- penis - delivery through erection, protrusion, emission and then ejactulation
what animals do not have a scrotum?
dolphin and elephant
what are the layers of the scrotum?
- scrotal skin
- tunica dartos
- connective tissue
- tunica vaginalis
what does the spermatic cord do?
what tissues form it?
What is contained within the spermatic cord?
1.links the testis to the deep inguinal ring
- visceral and parietal tunica vaginalis and external cremaster muscle
- testicular artery, veins, lympthatics, nerves.
What is specialised about the dog’s penis?
They have a bone in their penis, the prostate is the main gland and no distinct sigmoid flexure.
what is specialised about the TOMS penis?
spikes on head of penis - induces ovulation in the female
what adaptation do crocodiles have to transport semen in the water?
a glans phallus and sulcus - suctions
What is specialised in avian reproduction for females and males?
females only have one ovary where as males have 2 testes - both are functional
left is bigger than right
vas deferences opens into cloaca - urodeum
most birds dont have penis,
do amphibians have accessory gland? and how does sperm travel?
no and through the kidney urinary tract
How and why is it important to maintain testicular temperature?
- testicular vasculature - thermoregulation There is a countercurrent exchange in place at the pampiniform plexus (exchanges T as well) and coilded testicular artery
- action of the cremaster muscle - acts as a pump and draws the the testicles closer or away to the abdomen to alter the temperature
scrotal sweat glands cools down the testicles
scrotal skin is thermo-sensitive - sweating and respiration rate
- Tunica dartos muscle – When the muscle is relaxed, the skin is smooth, providing a greater surface area for heat loss. When the muscle is contracted the skin is wrinkled, providing more thickness and
insulation and so decreasing heat loss.
- Increased or decreased temperature results disruption to normal
spermiogenesis and an increase in % of abnormal sperm morphology
and motility
What do testis consist of?
- testicular capsule (visceral vaginal tunic and tunica albuginea)
- parenchyma (tubular - seminiferous tubules and interstitial – all other leydig cells)
- mediastinum
- rete tubules
What is the blood supply to the testicles?
testicular artery - directly from aort, to the kidneys follow decent of the the testis through the inguinal canal into the scrotum - coilds in the region of the spermatic cord reaching the testis
the coiled artery is associated with pampiniform plexus and cooled by by venous blood
What is the function of the testes?
production of gamete - seminiferous tubules and production of hormones in the leydig cells
What is the proposed hypothesis for benefits of scrotum?
decreased blood supply to scrotal testes lead to spermatozoa developing larger mitochondria which provides advantages in inter-ejaculate competition
what function do seritoli cells have?
- phagocytic - absorb bodies residual bodies
- secrete the fluid of the seminiferous tubules and rete testis
- produce estrogen in females
- produce ABP - androgen binding protein - which binds to T making it avaliable for stimulating spermatogenesis - controlled by FSH hormone
- produces inhibin - regulates neg feedback of release of FSH
- specialised junctions between sertoli cells
