Reproductive System Flashcards
Where is seminal fluid made
Bulbourethral gland
Seminal vesicles/gland
What is in the seminal fluid
Fructose Citric acid Bicarbonate Fibrinogen Fibrinolytic enzymes
What does the bicarbonate do in the seminal fluid
Neutralises acidic environment in the vagina
What does the fibrinogen and fibrinolytic enzymes in the seminal fluid do
Break doesn’t the barriers on the way to the egg
Penis muscles
2 x corpora cavernous
1x corpora spongiosum
What are errections due to
Erection is due to parasympathetic stimuli .parasympathetic system causes arteries to relax which puts pressure on venous drainage
What is ejaculation due to
Sympathetic stimuli
What are the layers of the testes( outside inwards)
Tunica vaginalis
Tunica albuginea
Tunica vasculosa
3 layers of uterus
Endometrium myomentum and perimetrium
Look at female reproductive tract diagram
Look at female reproductive tract diagram
Look at male reproductive tract diagram
Look at male reproductive tract diagram
Look up male reproductive tract diagram
Look at mail reproductive tract diagram
Sperm production in men
Gametogenesis begins of puberty
Spermatoginia undergo differentiation and self renewal
The pool is available for subsequent spermatogenic throughout life so they have continuous fertility
Produce approximately 1500 sperm/s
Egg cell production in women
Lots of logo is before birth - 6 mill/ovary
Rapid drop
By puberty very few remain as some primordial follicles degenerate ( atresia)
What do the Sertoli cells do
They produce the hormones required for sperm production
Reproductive hormones in males
Androgens : Testosterone, dihydrotestosterone and androsterone
Inhibin and activin - activate FSH
Oestrogens
Sertoli cells
Within the seminiferous tubules
They support developing germ cells
Hormone synthesis - inhibin and activin ( positive and negative effects on FSH)
Anti mullerian hormone ( to do with the Fallopian tube)
Androgen binding protein - gets the testosterone to the right place
What receptors do the Sertoli cells respond to
FSH
What do Leydig cells do
They are between seminiferous tubules
Pale cytoplasm as they are rich in cholesterol
Function ;
Hormone synthesis - androgens
On LH stimulation they secrete the androgens ;
- testosterone ( Oestrogens)
Androsterone
Dehydropieandrosterone ( DHEA) - they can be aromatised to Oestrogens
What receptors do leydig cells have
LH
When do babies start producing oocyte s
In 2nd trimester of pregnancy , all oogonia in fetus develop into 1 st oocyte s ( forming primordial follicles )
Then the 2nd oocyte s are produced during sperm fusion
Difference between spermatogenesis and oogenesis
Oogenesis produces more polar bodies
What does the follicle degenerate into ?
Corpus leuteum
What are the female reproductive hormones
Oestrogens ( oestradiol, Oestrogens, oestriol)
Progestogens ( progesterone)
Androgens ( testosterone, androstenedione, DHRA but not the DHEAs made in the adrenals)
Relaxin
Inhibin
Two types of cells in the ovary
Theca cells and granulosa cells
Theca cells location
Associated with the outer part of the ovarian follicles
Theca cells function
Support folliculogenesis
- structural and nutritional support of growing follicle
Hormone synthesis
LH stimulates synthesis of androgens
Overactivity due to PCOS can cause high androgen levels
Where are granulosa cells located
Associated with the inner part of the ovarian follicles
Function of the granulosa cells
Hormone synthesis
FSH stimulates granulosa cells to convert androgens to Oestrogens by aromatase
Secrete inhibin and activin - have effects on FSH
After ovulation - turn into granulosa luteein cells ( found in the corpus luteumO that produce
- progesterone
- relaxin ( helps endometrium prepare for pregnancy and softens pelvic ligaments/ cervix )
Gonadal sex steroid hormones
Oestradiol
Testosterone
Which hormones have a pulsating release
GnRH and LH and FSH
Which hormones have a diurnal release
Testosterone and Oestrogen
Prolactin and kisspeptin
Prolactin binds to prolactin receptors on kisspeptin neurones in the hypothalamus
This inhibits kisspeptin release
Decreases in downstream GnRH , LH , FSH , T , Oest
Oligomycin ( >35d menses) or amenorrhea ( 3-6m no menses) / low libido / infertility / osteoporosis
Look at menstrual cycle diagram
Look at menstrual cycle diagram
Does the body temp increase after ovulation
Day after ovulation , the body temperature increases by at least 0.5 degrees due to progesterone
Oestrogen is made from testosterone by which enzyme
Aromatase
Which hormone induced the tubular fluid reabsorption resulting in concentration
Oestrogen
Which hormone causes nutrients ( fructose) and glycoprotein secretion into epididymis fluid
Androgens
What is in semen
Spermatozoa
Seminal fluid
Leukocytes ( potentially viruses like hep B , HIV )
Very few spermatozoa actually reach ovum
Capacitation of sperm
Achieve fertilising capability in the female reproductive tract
1) lose protein coat
2) change surface membrane characteristics
3) develop whiplash movements of tail
What influences the capacitation of the sperm
Takes place in the ionic and proteolytic environment of the Fallopian tube
Oestrogen and calcium dependent
Acrosome reaction
Sperm binds to ZP3 ( sperm receptor )
Calcium influx into speed ( stimulated by progesterone )
Release Of hyaluronidase and proteolytic enzymes ( from the acrosome )
Spermatozoon penetrated the zona pellucida
Fertilisation
Triggers cortical reaction
Cortical granules release molecules which degrade zona pellucida ( eg. ZP3 and ZP2)
Therefore this prevents further sperm from bings as it has no receptors
Haploid - diploid
Development of the conceptus
The zygote can continue to divide as it moves down the Fallopian tube to the uterus ( takes 3-4 days)
Receives nutrients from uterine secretions
This free living phase can last for 9-10 days
Phases of implantation
Attaché,net phase ( outer trophoblast cells contact uterine surface epithelium)
Then
Decidualisation phase ( changes in underlying uterine stromatolites tissue - within a few hours )
Requires progesterone domination in the presence of oestrogen
Chemical Factors involved in the implantation phase
LIF and IL11
Leukaemia inhibitory factor
From endometrial cells stimulates adhesion of blastocyst to endometrial cells
Interleukin 11
Also from endometrial cells is released into uterine fluid and may be involved in attaché,net
What is decidualisation
Endometrial changes due to progesterone
- glandular epithelial secretion
- glycogen accumulation in stromatolites cell cytoplasm
- growth of capillaries
- increased vascular permeability
Which molecule is used as the marker for pregnancy
HCG as it can be only made by the placenta and so is only present when someone is pregnant
Progesterone and oestrogen production during pregnancy
First 40 days; produced in corpus luteum ( in maternal ovary)
Stimulated by HCG ( produced by trophoblast) which act on LH receptors
Essential for developing fetoplacental unit
Inhibits maternal LH and FSH ( -ve feedback) so no more energy released/ periods occurring during pregnancy
From day 40,
Placenta starts to take over
What hormones increase during pregnancy
ACTH Adrenal steroid Prolactin IGF1 Iodothyronones PTH related peptides
Decrease in maternal hormones during pregnancy
Gonadotrophins
Pituitary GH
TSH
What does oxytocin do in the control of parturition
Stimulates uterine contraction
Cervical dilation
Milk ejection
Hyperprolactonaemia
Have milk coming out of breasts due to too much milk synthesis so leaks out- galactorrhea.
