Chapter 15:reproduction in humans Flashcards
State function of ovaries
Organs that produce female gametes (eggs)
State function of oviducts (fallopians tube)
Tubes leading from the ovaries to the uterus
State function of uterus
The organ in which a fetus develops before birth;also known as the womb
State the function of cervix
A narrow opening leading from the uterus to the vagina
State function of vagina
Opening from the uterus to the outside of the body
State the parts of female reproductive organ
-fallopian tube (oviduct)
-ovary
-uterus wall
-uterus lining
-cervix
-vagina
State the parts I’m the male reproductive organs
-testis
-scrotum
-sperm duct
-epididymis
-penis
-Prostate gland
-urethra
-erectile tissues
define testis
organs in which the male gametes (sperm) are made
define scrotum
the sac that contains the testes
define sperm duct
a tube that transports sperm from the testis to the urethra
Define penis
Organs containing the urethra,through which urine and seem are carried
Define prostate gland
organs that produces a nutritious fluid in which sperm are transported
define epididymis
part of the testis in which sperm are stored
describe fertilisation
The fusion of the nuclei from the male gamete (sperm) and a female gamete (egg cell)
State the parts of the human sperm
-flagellum
-middle piece containing mitochondria for swimming
-head
-nucleus containing mitochondria to release energy for swimming
-acrosome : contains digestive enzymes
how far can sperms swim
4 m per minute
What happens when a sperm cell contacts the jelly coat
When is sperm cell contacts the jelly coat surrounding an egg cell is activated. It releases its digestive enzymes. And these enzymes digest the jelly coat.This allows the head of the sperm to push through and get into the cytoplasm of the egg. Only The head of the sperm goes in and the flagellum is left out.the nucleus of the egg fuses with the nucleus of the sperm - fertilisation
Define embryo
The ball of cells that is produced by repeated division of the zygote
Define implementation
attachment of the embryo to the lining of the uterus
How does implantation happen
1-ovulation-a mature follicle bursts,and releases an egg into the oviduct
2-fertilisation-a sperm nucleus fuses with the egg nucleus forming a zygote
3-the zygote divides
4-after several hours,a ball of cells is formed
5-the cells in the hall keep dividing as it moves down the oviduct.it is now a embryo
6-implantation-the embryo sinks into the soft living of the uterus
7-the placenta is formed
Define placenta
An organ that connects the growing fetus to its mother,in which the blood of the fetus and mother are brought close together so that materials can be exchanged between them
Describe the placenta
The placenta is soft,dark red and finger like projections called villi
Define fetus
An unborn mammal,in which all organs have been formed
Define umbilical cord
A structure containing blood vessels that connects the fetus to the placenta
What gets passed in the placenta
-Oxygen and dissolved nutrients in the mothers blood diffuse across the placenta into the fetus’s blood and are carried along the umbilical cord to the fetus.
-carbon dioxide and other excretory products diffuse in the direction and are carried away in the mothers blood
what are the unnecessary substances passed in the placenta
unwanted substances (carbon monoxide and alcohol) viruses which causes rubella are passed through the placenta
Describe the placenta after the baby is born
The placenta is a flat disc about 12 cm in diameter and 3 cm thick
define amniotic sac
a tough membrane that surrounds a developing fetus in the uterus
Define amniotic fluid
Liquid secreted by the amniotic sac which supports and protects the fetus
What’s a sign that a women is about to give birth
The contraction of muscles in the uterus wall often cause the amniotic sac to break,releasing the amniotic fluid so that it flows into the vagina
What is the main reproductive hormone produced in men
testosterone
What is the main reproductive hormone produced in women
oestrogen and progesterone
Define puberty
the time at which sextuplets maturity is reached
Define follicle
a structure within an ovary,in which an egg develops
Define mensuration
The loss of the broken down uterus living through the vigina
What hormones control the mensuration cycle
1-oestoegen
2-progesterone
3-FSH
4-LH
What is secreted by ovaries
Oestrogen and progesterone
What is secreted by the pituitary gland
FSH , LH
define FSH
FSH is the follicle stimulating hormone,a hormone secreted by the pituitary gland which causes a follicle to develop in ovary
define LH
Luteinising hormone a hormone secreted by the pituitary gland that causes ovulation to happen
Define pituitary gland
A small endocrine gland attached to the underside of the brain
Define menstrual cycle
1-inside the ovary,a follicle containing an egg cell develops.the uterus lining is repaired .the developing follicle secrets oestrogen in increasing amounts .oestrogen causes the lining to be thicker and better supplied with blood
2-ovulation-the follicle bursts releasing an egg cell from the ovary.the oestrogen level decreases,fertilisation could take place.
3-the follicle turns into a corpus luteum.this secretes progesterone so the concentration of progesterone increases.the lining of the uterus becomes more vascular,ready to receive the embryo
4-menstruation -as the egg has not been fertilised the thick uterus lining is not needed it breaks down and gradually lost through the vagina
What happens if the egg is fertilised
The preojestrone levels stay high.this happens because the corpus leteum remains in the ovary and continues to secrete projectrone,this helps to maintain the thick uterus lining so that the embryo can implant into it.once the placenta has developed,this takes over the role of screwing projestrone.
The high level of projestrone during pregnancy inhibit the secretion of FSH by pituitary gland,so no more follicle ps develop in the ovary
Define sextuplets transmitted infection (STI)
a disease caused by pathogens that are transmitted during sextuplets contact
How is a STU transmitted
By bacteria or viruses that can be passed from one person to another during sextuplets contact. Mainly (HIV / AIDS)
define AIDS
acquired immune deficiency syndrome,a disease caused by HIV,which destroys the white blood specks and therefore reduces the ability of the immune system to defend against other pathogen
define HIV
the human immunodeficiency virus
Where does HIV infect
HIV infects white blood cells specifically in T cells
What controls HIV
A drug called antiretroviral
How does antiretroviral help control HIV
they stop the virus from multiplying inside the persons cell
how do you get affected with HIV
direct contact of body fluids
How does a person become HIV positive
-through sexual contact
-through blood contact
-through breast feeding
How is HIV passed through sexual contact
-HIV can live in the fluid inside the vigina,rectum and urethra
-during sexual intercourse,fluids from one partner coke in contact with fluids of the other
-the more sexual partners a person has,the higher chance of them becoming infected with HIV
how do you prevent AIDS
-never have more than one sexual partner
-using a condom
-by knowing if you are infected by the virus so that health workers can trace the people who could have passed the virus on to
How is AIDS passed from blood contact
-a person sharing blood directly to another
-mother to child during child birth when blood of the mothers comes in contact with the baby
-sharing hypodermic needles when injected with drugs
How do you prevent AIDS through blood contact
-make sure the hypodermic needle used for injection is sterile
-wear protective gear when dealing with blood transfusions
-the ,other SHOUDL take in antireviral drugs
How is HIV transferred during breast feeding
-if the mother has HIV it can get into her breast milk and so be passed to the baby
how do you prevent HIV during breast feeding
Take antireviral drugs during pregnancy and breast feeding
