Reproductive System Flashcards
What is the function of the reproductive tract?
- Development, maturation and transport of gametes • Ovocytes (oocytes, egg cells)
- Spermatozoa
- Copulation
- Pregnancy and parturition (some species)
What makes up the female reproductive tract?
– Ovaries – Oviducts – Uterus
– Cervix
– Vagina
– Vulva
What are the ovaries
• Paired organ
• Oval shaped
• Except in the mare where they have a kidney-like
• Located inside the abdominal cavity
– However, the position inside the cavity varies depending on the species
• In carnivores, they are caudal to the kidneys
• In others they migrate to some degree, ruminants show the highest extent
What are the functions of ovaries?
– CytogenicOvocytes – Endocrine
• Oestrogens (in the cells of mature follicles) • Progesterone (corpora lutea)
- Oestrogens - follicle wall
- Behavioural signs of heat
- Preparation of genital tract for mating
- Reduces FSH production
- Increases LH production
- Progesterone
- Corpusluteum
- Essential for maintenance of pregnancy
- Prepares uterus for implantation of fertilised ovum
- Acts on mammary tissue to prepare for lactation
- Reduces FSH – prevents oestrus during pregnancy
What are the two zones of the ovary?
– Cortical
• Follicles and corpora lutea – Medulla
• Vascular
• Nerves
What is the uterine tube (oviduct) and what is it made up of?
• Paired organ • Receive and transport the ovocyte • Three portions: 1. Infundibulum • Funnel-like, receives the ovocyte using projections called fimbria 2. Ampulla • Where fertilisation occurs (If not, ovocyte is re-absorbed) 3. Isthmus • Joins the uterus
What is the uterus and what is it made up of?
• Site of implantation and placentation – Gestation
• Microscopically the wall consists of three layers: – Endometrium
– Myometrium
– Serosa
What species does fusion of the uterus occur in?
• Depending on the species, the caudal part of the uterus fuse
– In rodents the fusion is limited to the vagina • The uterus consists of paired tubes
– In primates fusion is more extensive and only the oviducts remain paired
• The uterus of the majority of mammals show an intermediate fusion pattern
• Hence, the uterus has the following components – Horns (paired)
– Body
– Cervix
What is the vestibule?
– Short portion of the vagina
– Its wall secretes a serous secretion
• It keeps moisture to facilitate coitus and parturition
• In oestrus it has a characteristic odour that stimulate the male
• Vestibular bulbserectile tissue
What is the vulva?
- Formed by two labia
- Body and glans (clitoris)
- The clitoris lies within a fossa covered by mucosal folds – Very prominent in mares during oestrus
- “Winking”
What is the male reproductive tract made up of?
– Testes – Epididymis – Deferent duct – Urethra – Accessory glands – Penis
What are the testicles and what are their two functions?
• Paired organ
• Usually they are located outside the abdominal cavity
• Two functions
• - CytogenicSperm cells
- Endocrine Androgens (testosterone) in the Leydig cells
Why does testicular descent occur?
– Testicular descent is vital for spermatogenesis
– Scrotal position decreases the temperature of the testis relatively to body temperature
– Failure of one or both testes to descend is called cryptorchidism (hereditary)
What are the tumulus rectus and rate testis?
• Each contorted seminiferous tubule is looped and where straighten out:
– They are called the tubulus rectus.
• They enter the mediastinum of the testis
• Open into a network of confluent tubules
• Rete testis
What are the efferent ducts?
- Each rete of the testis is drained by eight to twelve convoluted tubules called efferent ducts.
- The efferent perforate the fibrous capsule to enter the epididymis.
What is the epididymis and what are its three parts?
• It is firmly attached to the testicular capsule and receives the efferent ducts from the rete testis.
• It consists of a coiled tubular system which is held together by connective tissue.
• It can be divided in three parts:
1. Head
2. Body
3. Tail
• The efferent tubes join to form the duct of the epididymis
• This duct continues and becomes the tail of the
epididymis
• The duct of the epididymis continues
• Forms the deferent duct.
What are the functions of the epididymis?
• Its functions are: – spermatozoa maturation – absorption of testicular fluid – Nutrient secretion for spermatozoa – Storage until ejaculation
What is the deferent duct?
• It ascends to the abdominal cavity through the inguinal canal.
– Along with blood vessels, nerves and muscles they form the spermatic cord
• It ends in a thickened form
– This is called the ampulla
– In turn it ends in the urethra
What is the urethra and what are its two parts?
• Common duct for both the urinary and the reproductive system.
• Its function is to transport the sperm during ejaculation.
• It can be divided into two parts
1. Pelvic
2. Penile
What are the accessory glands?
Ampullary gland
Prostate
Seminal Vesicles (vesicular gland)
Bulbourethral gland (Cowper’s)
What is the ampullaes function (accessory gland)?
contribute fluid to semen
What is the Seminal vesicles function (accessory gland)?
– secrete alkaline fluid ( 60% of semen) containing:
• fructose
• prostaglandins
• ascorbic acid
What is the function of the prostate gland?
– produces alkaline secretion
– (with enzymes for sperm motility)
What is the function of the Bulbourethral gland?
– secretes alkaline mucus into urethra
• neutralises acidic urine
• provides lubrication for the penis
