16 | Reproduction in humans

Question 1

Function of testis

Answer 1

produces sperms and male sex hormones such as testosterone

Question 2

function of epididymis

Answer 2

stores inactive sperms from testis

Question 3

function of spermatic cord

Answer 3

supplies blood to testis

Question 4

function of scrotum

Answer 4

keeps the testes outside the main body so that sperms can develop properly at lower temperature

Question 5

function of sperm duct (vas deferens)

Answer 5

transport sperms from testes to the urethra

Question 6

function of seminal vesicle

Answer 6

stores sperms temporarily before they are released into the urethra

Question 7

function of prostate gland, cowper’s gland and seminal vesicle

Answer 7

release fluids that contain nutrients and enzymes that are needed to activate the sperm cells

Question 8

function of prostate gland

Answer 8

produces alkaline, milky fluid that contains nutrients and enzymes which nourish and activates the sperms and helps them to swim towards the egg.

Question 9

function of urethra

Answer 9

extends from the urinary bladder, through the penis, to the outside of the body where urine and semen are passed out.

Question 10

function of penis

Answer 10

erectile organ that becomes hard during sexual intercourse in order to enter the vagina to deposit semen containing sperm.

Question 11

parts of the sperm

Answer 11

head
middle piece
tail or flagellum

Question 12

head of the sperm

Answer 12

• about 2.5um wide
• contains a large nucleus with a small amount of cytoplasm. The nucleus carries a haploid set f chromosomes.
• an acrosome is also present. The acrosome is a vesicle containing enzymes. These enzymes break down part of the egg membrane so that the sperm can penetrate the egg during fertilisation

Question 13

function of middle piece of sperm

Answer 13

contain numerous mitochondria to provide energy for the sperm to swim towards the egg.

Question 14

function of tail or flagellum of sperm

Answer 14

enables sperm to swim towards the egg

Question 15

function of ovary

Answer 15

produce eggs/ova (singular: ovum) and female sex hormones such as oestrogen and progesterone

Question 16

function of oviduct (fallopian tube)

Answer 16

• narrow muscular tube leading from the ovary to the terus. It has a funnel-like opening close to the ovary. This makes it easier for the egg to enter the oviduct.
• transport eggs to the uterus by peristalsis of the muscular wall and sweeping action of the cilia.
• site of fertilisation

Question 17

function of the uterus.

Answer 17

• a muscular organ with thick walls that are rich in blood capillaries.
• contains soft and smooth uterine lining that allows the implantation of embryo
• site of implantation of embryo and fetus development during pregnancy.

Question 18

function of cervix

Answer 18

• a circular ring of muscles at the lower end of the uterus.
• allows menstrual bllood to flow out into the vagina during menstruation
• enlarges to allow passage of the fetus during birth

Question 19

function of vagina (birth canal)

Answer 19

where semen is deposited during sexual intercourse

Question 20

function of vulva

Answer 20

opening of the vagina

Question 21

ovum

Answer 21

• has a large nucleus containing one haploid set of chromosomes
• has abundant cytoplasm which may contain a small amount of yolk
• surrounded by a cell surface membrane which in turn is surrounded by an outer membrane.

Question 22

difference between male and female gamete

Answer 22

SMN
structure
motility
numbers

Question 23

define puberty

Answer 23

puberty is the stage of human growth and development in which a person’s body bcomes capable of reproduction

Question 24

what happens during puberty

Answer 24

during this period, the sex organs mature and sex hormones are released. The release of sex hormones result in the development of secondary sexual characteristics.

Question 25

what is menstruation?

Answer 25

menstruation is the process whereby blood is discharged from the uterus via the vagina.

Question 26

what is the average menstrual cycle?

Answer 26

28 days

Question 27

what is the range for the menstrual cycle

Answer 27

the menstrual cycle can range from 21 to 33 days

Question 28

changes in a follicle during the menstrual cycle

Answer 28

OVOC

Question 29

stages of the menstrual cycle

Answer 29

- menstrual flow (day 1-5) - follicle stage (day 6-13) - ovulation (day 14) - corpus luteum stage (day 15-28)

Question 30

what is the first day of the menstrual cycle?

Answer 30

the first day of menstruation is the first day of the menstrual cycle

Question 31

What happens during day 1-5?

Answer 31

- menstruation occurs - during menstruation, the uterine lining breaks down and flows out throught the vagina. - low levels of estrogen and progesterone - follicle-stimulating hormone (FSH) released by anterior pituitary gland into bloodstream which stimulates follicle development and oestrogen secretion by the follicles.

Question 32

What happens during day 6-13?

Answer 32

- FSH stimulates development of follicles in the ovaries and secretion of oestrogen. - oestrogen causes the repair and growth of the uterine lining. The uterine lining becomes thick and spongy with blood vessels. - oestrogen when present in high concentration inhibits FSH production, preventing maturation and development of more follicles. - oestrogen at high concentration also stimulates the pituitary gland to secrete luteinising hormone (LH)

Question 33

what happens on day 14?

Answer 33

- LH causes ovulation and formation of corpus luteum from the remains of the Graafian follicle - the corpus luteum secretes progesterone and some oestrogen.

Question 34

what happens on days 15-28?

Answer 34

- progesterone maintains the uterine lining by causing it to thicken further and be richly supplied with blood capillaries, preparing it for the implantation of the embryo -- inhibits ovulation -- inhibits FSH production

Question 35

what happens if fertilisation occurs?

Answer 35

if fertilisation occurs, the embryo secretes a hormone that prevents the corpus luteum from breaking down

Question 36

what happens if fertilisation does not occur?

Answer 36

If fertilisation does not occur, the corpus luteum will break down and hence, the uterine lining will not be maintained. It will be discharged throught the vagina (menstruation starts again)

Question 37

How long can an egg survive in the female reproductive system?

Answer 37

24h

Question 38

How long can a sperm survive in the female reproductive system?

Answer 38

approximately 3-4 days

Question 39

when is the fertile period?

Answer 39

days 11-16

Question 40

when does ovulation usually occur?

Answer 40

day 14

Question 41

what happens during the fertile period?

Answer 41

the chance of getting pregnant is higher between days 11-16 (fertile period). - the rest of the days in the menstrual cycle is known as the infertile period

Question 42

Define fertilisation

Answer 42

fertilisation is the process involving the fusion of the nucleus of a haploid male gamete and the nucleus of a haploid female gamete to form a diploid zygote

Question 43

Process of fertilisation

Answer 43

notes

Question 44

what is the amniotic sac?

Answer 44

- An amniotic sac develops and encases the embryo - the amniotic sac contains amniotic fluid, which allows the fetus to move within

Question 45

functions of the amniotic sac?

Answer 45

SLAPMT - support and cushions fetus before birth (S) - lubricates and reduces friction in the vagina during birth (L) - absorbs shock (if mother has a fall) (A) - protects fetus from physical injury (P) - allows fetus to move freely during growth, promoting muscular development (M) - prevent temperatre fluctuations (T)

Question 46

what is the fetal blood system?

Answer 46

the fetal blood system is separated from the maternal blood system. This is because the - mother's blood pressure is too high for the fetus - mother and fetus may have different blood types, and agglutination may occur.

Question 47

function of placenta

Answer 47

OF - ME - A - P - Allows oxygen and dissolved food substances to diffuse from mother's blood into fetus's blood (OF) - Allows metabolic waste or excretory products to diffuse from the fetus's blood into the mother's blood (ME) - allows antibodies to diffuse from the mother's blood into fetus's blood to protect the fetus against diseases (A) - produces progesterone which maintains the uterine lining in a healthy state during pregnancy (P)

Question 48

Functions of the umbilical cord

Answer 48

DM - OF - contains 2 umbilical arteries that transports deoxygenated blood and metabolic waste products from the fetus to the placenta (DM) - contains 1 umbilical vein that transports oxygenated blood adn food substances from the placenta to the fetus (OF)

Question 49

How can an STI be transmitted from an infected person to an uninfected person

Answer 49

via - semen or vaginal fluid - blood

Question 50

what is acquired immunodeficiency syndrome (AIDS)?

Answer 50

AIDS is a STI that is caused by the human immunodeficiency virus (HIV)

Question 51

what are the symptoms of AIDS?

Answer 51

FDPKBT - chronic or persistent fever (F) - severe diarrhoea that lasts for months (D) - Pneumonia (P) - Kaposi's sarcoma (K) - Brain infection (B) - Widespread tuberculosis

Question 52

How can aids be transmitted?

Answer 52

UHBP - Unprotected sexual intercourse with an infected person (U) - sharing of hypodermic needle with an infected person (H) - through blood transfusion with blood from an infected person (B) - substance exchange at the placenta (from infected mother to fetus) during pregnancy. (P)

Question 53

Prevention and control of HIV?

Answer 53

SCOBD - making sure needles used for hypodermic purposes are sterilised (e.g. for ear piercing or tattooing) (S) - using a condom during sexual intercourse (C) - keeping to a single sex partner, or abstaining from sex (O) - Do not share instruments that can break skin and get contaminated with blood (e.g. razors and toothbrushes) (B) - not abusing drugs as drug abusers are in the habit of sharing needles (D)