Male and female reproductive systems Flashcards
What part makes the sperm?
testicles
Where is the sperm stored and matured?
epididymis(behind testicle)
Which tube comes from the testes taking the sperm from the testes to the prostate?
Ductus (vas) deferens -surrounded by a spiral muscle that contracts to help the sperm along
Which 3 organs provide the seminal fluid?
- prostate
- seminal vesicles
- bulbourethral glands
What do the bulbourethral glands do?
- provide seminal fluid
- secretes pre-ejaculate(sugary, aids lubrication, emitted prior to ejaculation)
What does the seminal fluid contain?
- fructose(nutrients)
- citric acid(nutrients)
- bicarbonate(neutralise the acidic environment of the vagina)
- fibrinogen(thickening agent)
-Fibrinolytic enzymes(help the sperm break through to go find the egg)
Describe the spermatic cord location?
-formed at the deep INGUINAL RING and passes down the inguinal canal down to the testes
What are the main structures of the spermatic cord?
- Testicular artery
- Pampiniform plexus
- autonomic and GF nerves
- Lymph vessels
- Vas deferens
Why are the testes outside the body rather than inside?
-keeps them 2-3 degrees lower temp than the body which allows sperm production
What are the 3 muscles of the penis?
2x corpora cavernosa
1x corpora spongiosium
What causes erection and ejaculation?
erection(point)-Parasympathetic stimulation
Ejaculation(shoot)-sympathetic stimulation
What are the 3 layers of the capsule of the testes?
Tunica VASCULOA-rich in blood supply
Tunica ALBUGINEA
Tunica VAGINALIS-covers the testes and the epididymis
Where in the testes is sperm made?
SEMINIFEROUS TUBULES
There are 1-4 of these in each of the 300 lobules in the testes The lobules are seperated bySEPTA
Where in the testes is sperm temporarily stored?
RETE TESTES->EPIDERMIS->VAS DEFERENS
What are the 3 parts of the epididymis?
Tail, head, body
What is cut for male sterilisation?
Vas deferens
Where are the ovaries?
peritoneal cavity (remainder outside)
Where are egg released from and where do they go?
releases from the ovaries and caught by the fimbriae eggs then travel down the FALLOPIAN TUBE
describe 2 features of the fallopian tube?
CILLIA- which help to waft the egg towards the cental components
SPIRAL MUSCLES -help to move the egg
Where does fertilisation occur?
Widest part of the fallopian tube -AMPULLA
What happens if the cillia or muscles of the fallopian tube don’t work properly?
Fertilisation occurs further up in the fallopian tube resulting in ATOPIC PREGANANCY -embryo grows and ruptures the fallopian tube resulting in a HAEMORRAGE(very dangerous)
What is the uterus supported by?
tone of the pelvic floor muscles(levator ani and coccgeus) and 3 ligaments(broad, round, uterosacral)
What can cause uturine prolapse?
uterus descends into vagina
LOSS OF MUSCLE in the PELVIC FLOOR-can happen in elderly women
What is lining of the uterus?
ENDOMETRIUM- specialised inner layer of epithelial cellls MYOMETRIUM-muscle lining on the outside of the endometrium PERIMETRIUM-outer layer
What part of the uterus lining sheds during the luteal phase of menstration and why?
ENDOMETRIUM
progesterone levels drop= vasoconstriction of the arterioles in the endometrium= eskemia (causes the pain) =due to this and the necrosis this layer sheds once a month
What is 1cm lateral to the cervix?
ureter
What parts of the vagina are sterile and how is this maintained?
All areas superior to the cervix are sterile and below it(vagina ) is not maintained by :
- the monthly shedding of the endometrial lining
- thick cervical mucus that can block the entry of bacteria(thicker during luteal phase ). this is what the progesterone pill does this to stop sperm entering uterus
- narrow
- pH is less than 4.5 so is acidic
Why is the vagina acidic?
due to OESTROGEN = vaginal epithelium secrete GLYCOGENS
GLYCOGEN->ACID via vaginal bacteria
What are the arterial blood supplies in the female reproductive tract?
Ovaries: Ovarian arteries(from the aorta)
Uterus/vagina:uterine arteries (From internal iliac a)
Where does lymphatic drainage from the ovaries/testes and uterus/vagina go?
Ovaries/testes -para-aortic lymph nodes
Uterus/vagina-Iliac, sacral, aortic and inguinal lymph nodes
describe briefly a smear test?
cells taken from the EXTERNAL OS(opening of uterine cervix
) and examined under a microscope to look for anything abnormal that signifies cancer
What are the gonads in male and female?
Male-teste
s Female-ovaries
What are the 2 functions of the gonads?
- Gametogenesis
- Reproductive hormone production
Describe gametogenesis in men ?
- you have 6million germ cells(spermatogonia)
- gametogenesis begins at puberty
- spermatogonia undergo differentiation and self renewal
- due to self renewal there is always a pool of germ cells so men are always fertile
How much mature sperm do men produce per second?
1500
Describe gametogenesis in women?
- females start with 6million germ cells(oogonia) per ovary
- Oogonias form primary oocytes (primordial follicles)in the ovarian follicles
- Primardial follicles begin meiosis and get halted in the prophase
- some primordial follicles degenerate (atresia)
- at birth there is only about 2 million
- By puberty there may only be 0.5million per ovary due to further atresia
- therefore there is a limited germ cell supply in women which is why they have a menopause
describe spermatogenesis?
1-start with spermatogonia(diploid-2n)
2-spermatogonia undergo mitosis forming the primary spermatocytes (diploid 2n)
3-1st meiotic division to form secondary spermatocytes(haploid-n)
4-2nd meitotic division to form SPERMATIDS(haploid-n)
5-Differentiation-to form SPERMATOZOA(mature sperm-haploid)
Describe where gametogenesis occurs in the testes
spermatogonia start on the outer layer of the seminiferous tubules and as it matures it gets closer to the inner central part
What is the tunica propria?
basement membrane of the seminiferous tubules where there are lots of compact cells
What are the 2 cells of the seminiferous tubule?
SERTOLI cells- within the tubules
LEYDIG cells -ouside the seminiferous tubules
What 3 reproductive hormones are formed in the testes?
ANDROGENS (testeosterone, dihydrotestoterone, androstenedione)
INHIBIN- acts on th epititary to inhibit FSH secretion
OESTROGEN- aromatase converts testosterone to oestrogen
What does oestrogen do in men?
- Maintains bone mineral density
- helps EPIFISEAL PLATE FUSION (growth plates) to stop you being very tall
What does the sertoli cell do?
Has FSH receptors
SUPPORTS DEVELOPING GERM CELLS:
- assists the movement of the germ cells to the tubular lumen(centre of seminiferous tubules)
- transfer nutrients from the capillaries to developing germ cells
- Phagocytosis of damaged germ cells
HORMONE SYNTHESIS:
- Inhibin and activin(-ve and +Ve on FSH)
- secrete Anti-Mullerian hormone(stops a male feutus developing female reproductive system)
- Androgen binding Protein(important in transferring testosterone to sperm machinary of the seminiferous tubules)
What are the functions of the Leydig cells
- pale cytoplasm because they are CHOLESTROL RICH
- Have LH receptors
Function-Hormone synthesis:
-when stimulated by LH from the pituitary, ANDROGENS such as testosterone are secreted which can be aromitised to oestrogens
Describe Oogenesis?
1-Oogonia (diploid -2n)
2-In the 2nd trimester of pregnancy in the embryo ALL the oogonia -> primary oocytes via MITOSIS(forming primordial follicules) meaning there are no germ cells left, and then they are halted in Prophase
3- At MENARCHE(starting of the menstrual cycle) some of these primary oocytes -> secondary oocytes(haploid-n) via MEISIS I and here they emit a POLAR BODY(due to uneven seperation of the primary oocytes- eventually degenerates to leave one good secondary oocytes)
4- secondary oocytes are released by the ovary and when the sperm fuses with them they under second MEIOTIC division into OOTIDS and then DIFFERENTIATE into OVA (egg)
What is the difference between spermatogenesis and oogenesis?
With men there is a continous supply of germ cells due to the, being able to self renew, whereas supply is limited in women
What is folliculogenesis? Describe?
-development of the ovarian follicle
1-PRIMARDIAL FOLLICLE -contains the primary oocyte at birth
2-This becomes the PRIMARY FOLLICLE as it get surrounded by GRANULOSA CELLS AND THECA CELLS
3- These then mature to form SECONDARY FOLLICLES-fluid filled cavity (antrum) develops as well as FSH and LH receptors
4-MATURE FOLLICLE-forms halfway through the menstrual cycle and forms the secondary oocyteS
5-RUPTURED FOLLICLE-due to secondary follicle rupturing out of mature follicle
6- This degenerates into the CORPUS LUTEUM-where progesterone comes from which promotes pregnancy
What percentage of cycles in a woman are ovulatory?
80-90%
How can you tell if a patient has ovualated-testing if a women had reduced fertility?
- measure day 21 progesterone
- this should have risen if a corpus luteum has formed
- ultrasound-you cans see the corpus luteum
Describe the mature follicle?
Ovum(egg) in the middle surrounded by granulosa and theca cells
What reproductive hormones do the ovaries make?
What reproductive hromones do testes make?
Ovaries:
- OESTROGENS(oestradiol, oesrone, oestriol)
- PROGESTERONE
- ANDROGENS(testosterone, androstenedione, DHEA)
- RELAXIN(relaxes cervix and pelvic ligaments in preparation for child birth)
- INHIBIN-negative on FSH
Testes:
- Androgen(testerone, dihydrotesterone, androstenedione
- Inhibin
- Oestrogen(from testosterone)
What do the theca cells do?
-on the outer part of the ovarian follicles
Support foliculogenesis-structural and nutritional support of growing follicle
LH stimulates the synthesis of androgens
What does overactivity of the theca cells led too ?
High androgen levels his leads to PSOS in women
What are the 3 signs of PSOS?
- polycystic ovaries on an ultrasound
- clinical signs of high androgens e.g.acne
- impaired menstrual cycles(amenorrhea)
What is the function of the Granulosa cells?
assosiated with the inner part of the ovarian follicules
Hormone synthesis:
-FSH stimulates the granulosa cells to convert androgens to oestrogens (by aromatase)
-secrete inhibin and activin (these effect FSH)
After ovulation granulosa cells turn into GRANULOSA LUTEIN CELLS that produce:
- Progesterone(-ve feedback on FSH and maintain endometrium in case of pregnancy)
- Relaxin (helps endometrium prepare for pregnancy and softens the pelvic ligaments/cervix)
What is the initial precursor for steroid hormones?
cholesterol
Draw the hypothalamic pituitary gland axis?
Describe Hypothalamic-Pituitary Gonadal axis?
1-KISSPEPTIN neurones in the hypothalamus secrete KISSPETIN
2- this acts on kisspeptin receptors on GnRH neurones in the HYPOTHALAMUS
3-These neurones secrete GnRH which passes into local blood supply called HYPOPHYSEAL-PORTAL CIRCULATION in a pulsitile manner
4- goes from local circulation to GP(gonadotrophs) cells which make LH and FSH in the ANTERIOR PITUITARY gland
5-LH and FSH released into systemic circulation (goes round the whole body)
6- these hormones pass to the gonads to make predominantly testosterone and oestrogen (also makes some progesterone/activin/inhibin)
7- testosterone and oestrogen negatively/positively feedback (mostly negatively)directly onto the pituitary or onto the kisspeptin neurons
How would you describe the release of testosterone and oestrogen?
DIERNAL - higher levels in the morning and decreases towards the evening
This explains why men can often wake up with a boner
What is Hyperprolactinaemia?
disease caused by HIGH PROLACTIN levels causes the reproductive axis to shut down =amenorrhea
Describe how Hyperprolatinaemia happens?
1-Prolactin binds receptors on the kisspeptin neurones in hypothalamus
2-inhibits kisspeptin release
3-Decreases in downstream GnRH/LH/FSH/T/Oest
4-Oligo-amenorrhea/low libido/inferility/oesteoporosis
What happens on day one of the menstrual cycle?
1st day of bleeding- due to progesterone levels dropping
What are the 3 phases of the Ovarian cycle?
Day 1-13: FOLLICULAR PHASE-follicle formation
Day 14:OVULATION
Day 15-28:LUTEAL PHASE-corpus Leuteum forms preparing for potential pregnanacy
What is oligomenorrhoea?
When periods are more than 35 days apart
What happens to hormone level during the menstrual cycle?
-As the LH and FSH increase and follicle gets bigger you get more Oestrogen and once this reaches a high level the feedback becomes positive which results in the LS surge at day 14
LH surge-this help final stages of follicle maturation
- At day 15 follicle forms the corpus luteum which produces progesterone, progesterone rises which helps the endometriem be secretry for possible implantation
- Corpus Luteum dies if there is no pregnancy and therefore progesterone decrease and the cycle starts again
What is the Uterine cycle?
MENSTRUAL PHASE-shedding phase
PROLIFERATIVE PHASE-oestrogen driven phase
SECRETORY PHASE-preparation for pregnancy
What happens to body temperature the day after ovulation?
temperature increase by at least 0.5 degrees due to increase in progesterone
What is the arterial blood supply and lymphatic drainage of the testes?
Arterial-testicular arteries from the AORTA via the spermatic cord
Lymphatic drainage-PARA-AORTIC lymph nodes
