Human Reproduction Flashcards
what are testes
male gonad
gonad
organ that produces sex cells in animals
how are testes developed
developed in body but a few weeks before birth descend into scrotum
what temp is sperm kept at and why
35 - ideal for sperm production
role of seminiferous tubules
lined with sperm producing cells
what is between tubules & its function
interstitial cells - produce testosterone
how is epididymis formed
all seminiferous tubules combine
role of epididymis
sperm are stored and matured here
another name for sperm duct
vas deferens
relationship between sperm duct and urethra
epididymis ➡️ sperm duct which brings sperm to ➡️ urethra which carries sperm and urine ➡️ out of body
glands in male body
seminal vesicle
prostate gland
cowper’s gland
role of glands in body
produce seminal fluid
what does the production of seminal fluid do for the body
nourishes sperm and provides a medium for swimming
how is semen produced
seminal fluid and sperm
role of penis
release sperm into vagina
how is sperm produced
produced by meisos
meiosis
type of cell division
- cell divides and forms 4 daughter cells with half the number of chromosomes as parent cell
how many chromosomes in parent cell
46
how many cells in daughter cell
23
sperm producing cells are ________
diploid
diploid
cells containing 2 sets of 4 chromosomes
how many chromosomes do normal body cells contain
46
symbol for diploid cells
2n
describe haploid cells
- meiosis halves number of chromosomes so sperm cells are called haploid
- contain one set of chromosomes
what does the acrosome in sperm cells contain
contains digestive enzyme
nucleus of sperm cell contains:
23 chromosomes
what does the collar of sperm cell contain
contains many mitochondria
role of flagellum in sperm cell
causes sperm to swim
when are sperm cells produced
puberty
puberty
beginning of sexual maturity
name male hormone
testosterone
role of testosterone
develops primary and secondary male sexual characteristics
what do primary sexual characteristics dictate
presence of reproductive parts
what do secondary sexual characteristics dictate
features distinguishing males from females (apart from sex organs)
name some secondary male characteristics
body, facial and pubic hair
enlarged larynx - causes breaking of voice
increased muscular and bone development- wider shoulders
growth spurt
increased secretion of sebum in skin
role of ovaries
production of eggs and female hormones
how are eggs in body produced
meiosis
what surrounds egg in ovary
graafian follicle
role of graafian follicle
produce oestrogen
what is corpus lutuem also known as
yellow body
role of corpus lutuem
secretes progesterone
process of egg production in ovaries
- at birth female foetus contains all potential eggs from birth, they are diploid cells.
- after puberty, a number of eggs are produced monthly by meiosis.
- one egg continues to grow and the rest die off
- the egg is surrounded by graafian follicle
- when mature, follicle forms a swelling on the outside of ovaries
- this swelling bursts at ovulation to release egg
- after ovulation, follicle fills with yellow cells and become corpus luteum
how long is the menstrual cycle
28 days
role of menstrual cycle
produce egg and prepares body for pregnancy
how long do women partake in the menstrual cycle
begins at puberty, ends at menopause
menopause
end of a woman’s reproductive life
what occurs day 1 - 5 of menstrual cycle
- old lining of endometrium breaks down and sheds, loss of blood and tissue (menstruation/period)
- new egg is produced in ovary by meiosis and surrounded by graafian follicle
menstruation/period
loss of blood and tissue
what occurs day 6 - 14 of menstrual cycle
- developing graafian follicle produces oestrogen
- this causes the endometrium to build up again to prepare for implantation
- it also prevents the development of more eggs
what occurs day 14 of menstrual cycle
(ovulation) graafian follicle bursts which releases egg into the fallopian tube
what occurs day 14 - 28 of menstrual cycle
- graafian follicle turns into corpus lutuem
- this causes endometrium to thicken further and also prevents formation of new eggs
- on day 16, egg dies if its not fertilised
- days 12 - 16 are the fertile period
- at around day 22, if fertilisation doesn’t occur corpus lutuem will begin to degenerate, resulting in reduced progesterone levels
- as a result, on day 28, the endometrium breaks down
- cycle repeats
when is the fertile period of a menstrual cycle
days 12 - 16
ovum
egg
ova
eggs
how long can sperm live in female body
7 days
what is the reason for the fertile period beginning on day __ ? name day and explain
- day 14
- sperm may already be present in body