Reproductive System Flashcards
What is adolescence?
- Transitional phase from childhood to adulthood
- Teenage year (13-19)
- Increased period of growth and development.
What are the two hormones used in the reproductive system?
- Luteinising Hormone (LH)
- Follicle Stimulating Hormone (FSH)
Where are the reproductive hormones produced?
Anterior Pituitary Gland
What is the function of Luteinising Hormone (LH)?
Girls: increased levels trigger ovulation
Boys: Stimulates Leydig cells to make testosterone
What is the function of Follicle Stimulating Hormone (FSH)?
Girls: Initiates follicular growth
Boys: Induces Steroli cells - spermotogenesis
Where is oestrogen made?
Ovaries
How does FSH affect oestrogen level?
- FSH stimulates the ovarian production
- FSH promotes development of secondary sexual characteristics
What effects do progesterone have on the body?
- Development of the mammary gland in females
- Develops with prolactin during pregnancy
- Thickens endometrium for implantation
Where is testosterone secreted?
The testes (some secretion in ovaries)
How much higher are testosterone levels in males than females?
7-8 higher than females
What effects do testosterone have on the body?
Development of secondary sexual characteristics
- Penile/clitoral enlargement
- Increased libido
- Hair growth
- Increased muscle mass
- Broader shoulders
- Voice deepening
What effects do hormones have on emotion?
Mood swings
Frustration/irritability
Sexual desires
Self esteem
What is adrenarche?
onset of androgen dependent changes e.g. pubic and axillary hair, BO, acne
What is thelarche?
Female breast development
What is puberty?
Development of secondary sexual characteristics. Attain reproductive capacity
What is menarche?
Menstruation
Where are reproductive hormones released from?
Hypothalamus (Gonadotrophin releasing hormone GnRH and LHRH) Pituitary gland (LH and FSH)
In girls, which hormones effect which sexual characteristic?
- LH and FSH act on the ovary
- Oestrogen acts on breast growth, vaginal growth, clitoris growth
- Progesterone acts on vaginal and uterine growth and initiation of the menstrual cycle
In what order does sexual development start in girls?
Breast growth -> acceleration in height -> pubic and axillary hair growth -> menarche
In boys, which hormones effect which sexual characteristic?
- LH stimulates Leydig cells to produce testosterone
- FSH binds to receptors on the Sertoli cells, enhancing
spermatogenesis
In what order does sexual development start in boys?
Testicular growth -> growth of penis, pubic and axillary hair growth -> acceleration in height -> voice deepens, facial hair growth
How many stages are there in genital staging?
Five
What are the primary and secondary sex organs in females?
Primary - ovaries
Secondary - fallopian tubes, uterus, vagina
What are the primary and secondary sex organs in males?
Primary - testes
Secondary - ducts, glands, penis
Features of the testes?
- produce sperm cells
- developed from germ cells in seminiferous tubules
- secrete testosterone by interstitial/Leydig cells
Features of Leydig cells:
- found next to the seminiferous tubules in the testicle
- produce testosterone in the presence of Luteinising Hormone
Features of the scrotum:
- Protects the testes and maintains the temperature of the testes 2 degrees lower than body temp
- dual chambered
- located under the penis
- one is typically lower than the other
Features of the epididymus:
- storage site of sperm cells
- absorbs about 90% of the fluid secreted by the testes
- sperm remains here for 40-60 days (absorbed if not ejaculated in time)
What is semen?
- Fluid expelled during orgasm
- Mixture from secretions from the epididymus, seminal vesicle, prostate and bulbourethral gland.
- Main constituents are sperm, fructose, clotting and anti-coagulant factors and prostaglandins.
Why does semen contain fructose?
- produced by the seminal vesicles
- provides a source of energy for the sperm
Why does semen contain clotting and anticoagulant actors?
- produced by the seminal vesicles and prostate
- semen clots like blood, after 15-30 mins, anticoagulant factors dissolve the clot
Why does semen contain prostaglandis?
- produced by the prostate and seminal vesicles
- stimulate peristaltic contractions of the female reproductive tract that may help draw semen into the uterus
Main parts of a sperm:
- Acrosome - enzymes used to dissolve a path to penetrate the egg
- Nucleus - genetics
- Mitochondria - produce ATP for sperm motility
What is the male sexual response?
- Erection of the penis allows penetration into the female vagina
- Ejaculation expels semen into the uterus
What is ejaculation?
- It is initiated by sympathetic nervous impulses
- the ducts and accessory glands contract, emptying their contents into the urethra
- the urethral sphincters constrict
- the bulbospongiosus muscles of the penis contract rapidly and rhythmically, propelling semen into the urethra
What is the refractory period?
A period following ejaculation and lasting from 10 minutes to a few hours, where it is impossible to attain another erection and orgasm.
Features of the ovaries:
- produce oocytes (oogenesis) , most primary oocytes undergo a process of degeneration called atresia. Only one oocyte is ovulated each 28 day cycle.
What hormones do the ovaries produce?
- Oestorgen
- Progesterone
- Inhibin
- Androgens
Features of the fallopian tubes:
- the cilia beat towards the uterus
Features of the uterus:
- harbours the embryo
- provides nutrients
- expels the foetus at the end of its development
Features of the vagina:
- Contain striated squamous epithelium
- Bacteria ferment glycogen to lactic acid, resulting in a low vaginal pH
What are the features of accessory glands of the female reproductive system?
They keep the vagina moist and provide most of the lubrication for intercourse
What is oogenesis?
Egg production
