Human Reproduction Flashcards
What is the definition of fertilisation?
Fertilisation is when a sperm cell fuses with an egg cell
Where does fertilisation occur?
The fallopian tube
When an egg and a sperm cell fuse, what do they form?
A zygote
What is a gamete?
A sex cell
Give two examples of gametes:
An egg cell
A sperm cell
What is the next stage of development after an embryo?
A fetus
Name 2 types of reproduction
Sexual reproduction, asexual reproduction
Give 4 examples of asexual reproduction:
Bacteria, yeast, plants, jellyfish
Give 4 examples of sexual reproduction:
Fish, reptiles, birds, insects
Give 2 adaptations of an egg cell:
The size of the egg- allows more space for nutrients to be stored inside the cell
Nucleus- contains genetic information of the mother
What is the difference in formation between identical and non-identical twins?
Identical: one egg splits in half and only one sperm cell fertilises the egg cell
Non-identical: 2 egg cells are fertilised by 2 sperm at the same time
What is the female hormone used in puberty?
Estrogen
What is the function of the amniotic sac?
It surrounds the fetus during pregnancy, protecting the fetus from injury.
What day on the menstrual clock does ovulation occur?
Day 14
Why does the uterus lining break down?
Because it builds itself up when an egg is released, but if it is not fertilised, then the lining breaks down and bleeds
How do substances pass from the fetus to the mother and back? Give examples of these substances:
The placenta lets substances pass between the two blood supplies: oxygen and nutrients diffuse across the placenta from the mother to the fetus. Co2 and other waste products diffuse from the fetus to the mother.
Function of ovary:
The ovaries are a pair of female glands where the eggs form and where the female hormones are made
Uterus lining function:
To nurture the fertilised age that develops into a fetus and holding the baby till its mature enough for birth
Function of the sperm duct:
To move sperm away from its storage place in the testes
Function of testes:
To make sperm and to produce testosterone
Name 5 changes boys experience through puberty:
- voice deepens
- pubic hair grows
- testes start to make sperm cells
- testes and penis get bigger
- shoulders get wider
Name 5 changes females experience through puberty:
- breasts develop
- ovaries start to release eggs
- hips get wider
- pubic hair grows
- stronger body smell
What is the name of the period of life between puberty and adulthood?
Adolescence
3 ways a sperm cell has adapted to its function:
- a flagellum (tail) to help it to swim up the fallopian tube
- a nucleus to carry the genetic information of the father
- lots of mitochondria so it has lots of energy to swim to the egg cell
Function of penis:
Organ which passes semen and urine of the man’s body (but not at the same time)
Function of bladder:
Stores urine
Function of glands:
Produces fluids that provide the sperm with nutrients. This mixture of sperm and fluid is called semen
Function of sperm duct:
Tube through which sperm travels on the way to the glands
Urethra function:
The tube inside the penis that carries the urine or semen. A ring of muscle makes sure that there is no chance of urine and semen getting mixed up
Testes function:
Organs which make the male gamete, sperm and also the hormone testosterone
Foreskin function:
Skin that protects the end of the penis
Scrotum function:
A bag of skin which holds the testes
Epididymis function:
Tubes that store sperm for future use
Ovary function:
Produces the female gamete, the egg (ovum)
Oviduct function:
A tube lined with tiny hairs called cilia, that connect the ovaries to the uterus
Uterus function:
A muscular bag in which a baby develops until it’s birth
Lining of uterus function:
This part of the uterus is shed during a menstrual period
Cervix function:
A ring of muscle at the neck of the uterus that closes the uterus until the baby is ready to be born
Vagina function:
A muscular tube that leads from the cervix to the outside of the woman’s body. A man’s penis goes here during sexual intercourse
Clitoris function:
The button-shaped bump above the urethra and vagina
Labia function:
The folds of skin that cover the openings to the vagina and the urethra
Why does the penis lie outside the body cavity?
Because outside the body (or room temperature) is the perfect temperature for semen to be stored at
Function of placenta:
Supplies Oxygen, supplies glucose, removes co2, removes waste products, barrier to prevent blood mixing
What is it called when the egg is buried into the uterus lining?
Implantation
Why is the uterus lining maintained?
Lining is maintained for the blood supply needed for implantation and to supply oxygen for the implanted egg
What substances can pass across the placenta from the fetus to the mother?
Carbon dioxide, waste products, urea
What substances can pass across the placenta from the mother to the fetus?
Oxygen, digested food, glucose, antibodies, drugs, alcohol, microbes such as HIV and rubella
