human reproduction Flashcards
what is meant by the term secondary sexual characteristics
characteristics that develop at puberty
give two examples of secondary sexual characteristics present in males
deepening of voice
growth of body hair
give a function of the epididymis
matures and stores sperm
how may chromosome are found in the nucleus of a typical human sperm cell
23
suggest one possible cause of male infertility
low sperm count
how long is the typical menstrual cycle in a human female
28-31 days
describe one effect on the female reproductive system of the low level software oestrogen and progesterone
menstruation
why does oestrogen levels increase after approximately 5 days
follicle secretes moe oestrogen
what event occurs around day 14 of the menstrual cycle
ovulation
ovulation is causes by a surge in a hormone released from the pituitary, name this hormone
LH
explain why progesterone levels increase in the days after day 14
corpus luteum secretes progesterone
name a hormone involved in sperm production
testosterone
explain the importance of meiosis in the production of sperm
to proudce haploid cells
give one corrective measure for the cause of male infertility
in vitro fertilisation
give two roles of the placenta
production of hormones
prevent bloods from mixing
give an outline description of the birth process, including the role of hormones
-change in hormone levels causes contractions
-water breaks
-cervix dilates
deliver- head of the baby is forced out through the vagina
-afterbirth of the placenta
-umbilical cord is cut
state one method of birth control
contraceptive pill
name the hormone responsible for milk production
prolactin
state two biological benefits of breastfeeding
transfer of antibodies fro mothers to baby, balanced diet for baby
name two tissues involved in the formation of the placenta
uterine
embryonic
describe the difference between the male and female type of gametes - relative numbers of each produced
male - a high number of sperm
female - a low number of eggs
describe the difference between the male and female type of gametes - frequent of production of gametes
male-continuously
female - monthly
describe the difference between the male and female type of gametes - relative size
male - small
female - large
what is the role of the menstrual cycle
to prepare for pregnancy
name the event that occurs between days1-5 of the cycle
menstruation
mesntraution is triggered by a large drop in a certain hormone,name the hormone
progesterone
name the structure that the Graafian follicle develops into after day 14
corpus luteum
give an example of a natural contraception method
rhythm method
give an example of a mechanical contraception method
condom
give an example of a chemical contraception method
contraceptive pill
give an example of a surgical contraception method
vasectomy
what is meant by the term implantation
the embedding of the blastocyst in the endometrium
name, in the correct order, the developmental stages from e fertilised egg to implantation
-morula
-blastocyst
outline what happens to the level of the hormone progesterone in the blood after implantation
increases
outline what happens in the endometrium after implantation
is maintained
embryo cells organise into three germ layers, name each of these layers
ectoderm, endotherm, mesoderm
explain the term in vitro fetilisation
gamets fuse outside the body
suggest a reason for the removal of several eggs
to increase of successful implantation
identify the germ layer from which the skin of the developing embryos arises
ectoderm
from which tissues does the placenta form
endometrium
give two reasons why mixing blood must not occur
blood pressure difference
prevent transfer of certain infections
state one change that occurs and the approximate days of the cycle on which it occurs in th endometrium
breaks down
days 1-5
state one change that occurs and the approximate days of the cycle on which it occurs in the ovary
follicle matures
days 1- 14
where are the hormones FSH and LH produced
pituitary gland
state one role of FSH
stimulates secretion fo oestrogen
state one role of LH
stimulate ovulation
state two other hormones that play a role in the cycle
oestrogen, progesterone
give a function of oestrogen in the cycle
inhibits the FSH
give a function of progesterone in the cycle
inhibits the secretion of FSH and LH
suggest a reason why a sperm cell needs so many mitochondria
needed for swimming to the egg
mitochondria are inherited exclusively from the mother, suggest why this is the case
only the head enters the egg
state the survival time of the egg and the sperm in the female body
egg-12-48 hours
sperm-0-7 days
