3A specifically human reproduction + menstruation - PART OF REPRODUCTION

Question 1

what is the structure of the male reproductive system? - gamete

Answer 1

sperm cell:
head which has the nucleus and acrosome, a sac of digestive enzymes to break down/penetrate the membrane of the egg.
midpiece with mitochondria which releases energy for movement
tail (flagellum), for proulsion/to swim
smallest cell in body

Question 2

what is the structure of the egg?

Answer 2

large, big, mitochondria, biggest cell in a human

Question 3

can you name and label all the things in the female reproductive system?

Answer 3

the womb, the oviduct (fallopian tubes), bladder, ovary, cervix, rectum, anus, urethra, vagina, front pelvis
ligaments hold ovary in posisiton, muscular womb

Question 4

what happens in the female reproductive system

Answer 4

each month, an egg is released from the oviduct from the ovary. This is ovulation. If an egg is present in the oviduct then it may be fertilised by sperm introduced during intercourse. The zygote formed will begin to sevelop into an embryo, which will implant into the lining of the uterus. Here the embryo will develop into a placenta, which will allow the embryo to obtain materials such as oxygen and nutrient’s from the mother’s blood. it anchors embryo to uterus, gets rid of waste products, maintains pregnancy

Question 5

be able to label the male reproductive system

Answer 5

bladder, seminal vesicle, sperm duct, penis, urethra, testes, foreskin, scrotum

Question 6

where is the sperm made and travel when leaving the body

Answer 6

sperm made in testes
sperm travels down sperm duct and urethra

Question 7

what is the head of the penis protected by

Answer 7

foreskin

Question 8

what adds special liquids to sperm cells to make semen

Answer 8

seminal gland

Question 9

what holds the fetus inplace

Answer 9

cervix

Question 10

where does baby develop

Answer 10

uterus

Question 11

whwere is the egg released form and where does it travel down

Answer 11

ovary and fallopian tube

Question 12

what is the function of the labia? female

Answer 12

Folds of tissue which surround and protect the clitoris and the openings of the vagina and urethra

Question 13

what is the function of the oviduct? female

Answer 13

Carries egg to uterus, site of fertilisation

Question 14

what is the function of the rectum? female

Answer 14

Stores faeces before egestion

Question 15

what is the function of the cervix? female

Answer 15

Controls entry of sperm into the reproductive system
a ring of muscle at the lower end of the uterus; keeps the fetus in place during pregnancy

Question 16

what is the function of the urethra? female

Answer 16

Tube through which urine exits the body

Question 17

what is the function of the endometrium? female

Answer 17

Embryos implants here, the site of foetal development

Question 18

what is the function of the uterus wall? female

Answer 18

Muscular wall to push foetus out using contractions during birth

Question 19

what is the function of the clitoris? female

Answer 19

Small zone of sexual pleasure found above the entrance to the vagina

Question 20

what is the function of the ovary? female

Answer 20

Produces ovum cells and releases one (mature egg) every 28 days

Question 21

what is the function of the vagina? female

Answer 21

Receptacle for penis and sperm in sexual intercourse

Question 22

what is the function of the bladder? female

Answer 22

Stores urine before excretion

Question 23

what is the function of the seminal gland + prostate? Male

Answer 23

Produce the liquid that mixes with the sperm to form semen

Question 24

what is the function of the testes? Male

Answer 24

Sperm are produced here

Question 25

what is the function of the anus? Male

Answer 25

Base of the lower intestine, through which faecal matter exits the body

Question 26

what is the function of the erectile tissue? Male

Answer 26

Is filled with blood when aroused to allow the penis to become hard

Question 27

what is the function of the bladder? Male

Answer 27

Urine is stored here after production in the kidneys

Question 28

what is the function of the foreskin? Male

Answer 28

Layer of skin and muscle that covers and protects the glans of the penis

Question 29

what is the function of the scrotum? Male

Answer 29

Sack of skin and muscle which contains the testes, helps to regulate their temperature

Question 30

what is the function of the glans? Male

Answer 30

Tube that urine and sperm leave the body through

Question 31

what is the function of the penis? Male

Answer 31

The tip of the penis, zone of sexual pleasure Is used to get sperm into the female

Question 32

what is the function of the sperm duct? Male

Answer 32

Tube the sperm travel through during sexual intercourse (and urine)

Question 33

describe fertilisation fully (in humans)

Answer 33

1. whena man and a woman have sexual intercourse, the man’s penis fills with blood and becomes erect
2. then the woman’s vagina produces a slippery fluid. eventually the sperm in the man’s testicles will travel along the vas deferens and past the glands where a nourishing fluid is added to the sperm
3. this forms semen. the semen contains a lot of glucose (sugar), which gives the sperm the energy they need to swim which they do by flicking their tails from side to side
4. the semen flows out the penis (ejaculation). the semen is deposited inside the woman’s vagina
5. the sperm must now have a very long journey. they must wim througout the cervix into the uterus of the woman
6. here some of the sperm swim up the fallopian tube whilst the rest of the sperm swim up the second fallopian tube
7. it is in the fallopian tube that the sperm may meet an ovum. one sperm cell will swim into the egg cell. once inside, the nucleus of the eff cell and the nucelus of the sperm cell will fuse together forming a embryo
8. the fusion is called fertilisation. the fertilised egg will now travel to the uterus where it will attatch to the wall and begin dividing, eventually forming a fetus that will be born in 9 months time

Question 34

when do men and women gwt their gametes?

Answer 34

fwemales have their undeveloped egg cells in their bodies since birth
males produce new sperm continously once they reach puberty

Question 35

wyat type of cells are the embryo/zygote?

Answer 35

embryotic stem cells

Question 36

when is the zygote a embryo?when is the embryo a fetus?

Answer 36

the embryo turns into a fetus when the cells begin to differentiate into different organs and tissue. After 11 weeks the developing huma turns into a foetus

Question 37

label a placenta. it needs to to contain a :

Answer 37

umbilical cord, placenta, amnion, amniotic fluid, uterus, cervix, mucus plug, vagina

Question 38

what is the function of amnion?

Answer 38

protects the embryo from physical harm using the amniotic fluid

Question 39

what is the function of placenta?

Answer 39

provides nutrients and materials to the embryo and removes waste products such as CO2

Question 40

what is the function of umbilical cord?

Answer 40

connects foetus to placenta

Question 41

what does the placenta transfer and recieve?

Answer 41

the placenta gives oxygen, minerals like carbon (to build skeleton, amino acids), glycerol and fatty acids, and glucose and CO2, excess water, urea is returned

Question 42

what doesnt the placenta allow to cross?

Answer 42

molecules

Question 43

why is the placenta good?

Answer 43

most diseases, bacteria, can’t cross the placenta, protecting the baby form infection. However some virus’ like HIV can as they are much smaller. Chemicals like alcahol and nicotine are also small and can pass through

Question 44

why must the baby’s blood and mother’s blood not mix?

Answer 44

so pathogens don’t go to the baby and different blood types can’t mix

Question 45

by which process do substances pass between mother and fetus’ blood in placenta?

Answer 45

diffusion

Question 46

how is the placenta adapted for its function?

Answer 46

high SA to vol ratio - (chorionic villi)
short diffusion distance - 1 cell thick
dense network of foetal blood vessels

Question 47

other than exchanging materials, what does the placenta do?

Answer 47

anchors the embryo in the uterus
the placenta secretes female hormones, in particular progesterone, which maintains the pregnancy and prevents the embryo from aborting (being rejected by the mother’s body)

Question 48

what encloses the embryo during pregnancy? what is it filled with? why?

Answer 48

a membrane called the amnion encloses it. it is filled with amniotic fluid which protects the developing embryo against sudden movements

Question 49

what are the 3 stages to birth?

Answer 49

1. dilation of the cervix - it gets wider to allow the baby to pass through, the muscles of the usterus contract quite strongly and tear the amnion, allowing the amniotic fluid to escape
2. delivery of the baby - stong contractions in the uterus push the baby’s head through the uterus into the cervix and vagina
3. delivery of afterbirth- the uterus contracts to push the placenta out together with membranes hat surround the baby

Question 50

which hormones are introduced during puberty to allow both sexes to allow for reproduction? What do they stimulate?

Answer 50

follicle stimulating hormone (in boys it stimulates sperm production), luteinising hormone (in boys it instucts the testes to secrete the male sex hormone, testosterone which controls the developmnet of the male secondary sexual characteristics e.g., growht of penis, testes, faacial and body hair)
in girls, the pituitary hormones contol the release of female sex hormones called oestrogen, from the ovaries. Oestrogen produces the female secondary sexual characteristics such as the beginning of menstruation

Question 51

list changes in puberty for boys

Answer 51

sperm production starts, growth and development of male sexual organs, growth of armpit and pubic hair aswell as chest and facial hair, increase in body mass (muscle), voice breaks, secual ‘drive’ develops

Question 52

list puberty changes in girls

Answer 52

menstruation begins, growth and development of female sexual organs, growth of armpit and pubic hair, increase in boy mass (rounded shape to hips), voice deepends without sudden breaking, sexual ‘drive’ develops, breasts develop

Question 53

describe the different stages of menstruation cycle

Answer 53

roughly:
1-5 menstruation (lining shed)
6-13 new lining of uterus develops (new egg matures in ovary)
14- ovulation: egg shed from ovary (can be fertilised)
15-20 egg in oviduct (it dies if not fertilised)
21-28 blood supply develops in new uterus lining

Question 54

what is a follicle? what does it do?

Answer 54

inside a woman’s ovaries are hundreds of thousands of cells that could develop into mature eggs. every month, one of these grows inside a ball of cells called a follicle. At the middle of the cycle the follicle moves towards the edge of the ovary and the egg is released as the follicle bursts open (ovulation). After, the corpeus luteum grows and breaks down

Question 55

what is FSH? where is it released from? what is its function?

Answer 55

released from the pituitary gland
(follicle stimulating hormone)
causes the follicle ot mature
causes levels of oestrogen fro ovaries to increase

Question 56

what is oestrogen? where is it released from? what is its function?

Answer 56

released form ovaries
- high levels due to high FSH, causes lining of uterus to built up, cuases levels of LH to rise and levels of FSH to fall

Question 57

what is LH? where is it released from? what is its function?

Answer 57

released from pituitary gland
(luteinising hormone)
peaks due to high oestrogen
peak causes ovulation (the egg leaves the follicle in the ovary and is wafted down the oviduct)

Question 58

what is progesterone? where is it released from? what is its function?

Answer 58

released form the corpus luteum
- empty follicle of the corpus luteum rleases it and it maintains the uterus lining - lots of blood vessels
- it inhibits FSH to prevent ovulation
- the levels decrease as the corpus luteum breaks down and therefore allows FSH to increase

Question 59

give a summary of the hormones in the female reproductive system (what does it increas/inhibit)

Answer 59

FSH causes follicle to mature + oestrogen ↑
oestrogen causes lining to build up, LH ↑
LH causes egg to release, leaving the empty follicle
the empty follicle releases progestorone (↑)
progesterone and oestrogen inhibit FSH
progestorone inhibits LH

Question 60

which hormones cause secondary characteristics?

Answer 60

testosterone, oestrogen