Reproduction Flashcards
How is an insect pollinated plant adapted to attract insects?
colourful petals
nectar
sticky pollen
what is pollination?
the transfer of pollen from the anther of a flower to a stigma of another flower.
what is reproduction?
the process that increases the number of individuals of a species.
asexual reproduction?
- only one parent involved
- offspring genetically identical to parent
- no fertilisation involved
sexual reproduction?
- two parents
- offspring are genetically varied
- involves sex cells called gametes
- fertilisation is needed
what is fertilisation?
the joining together of the nuclei of the gametes.
what are gametes in animals called?
eggs and sperm
what is a zygote?
a fertilised egg
what is an embryo?
the zygote divides many timed to produce a ball of cells, an embryo.
what us the male part of a flower?
stamen
what is the female part of a flower?
carpel
where is pollen made?
anther
what are some wind pollinated plants characteristics?
no petals filaments on the stamens are very long anthers hang outside flower stigma long and feathery - hangs outside flower do not make nectar.
what does the ovule become in a plant?
seed
what does the ovary become in a plant?
fruit
how does the ovule become the seed?
hardens and dries out
how does the ovary become the fruit?
ovary wall swells up
what conditions are needed for germination?
warmth - so enzymes can work
oxygen - respiration
water - for all living processes
what is the function of ovaries?
make eggs
what is the function of the testes?
make sperm cells and hormone testosterone.
what does fertilisation involve in animals?
the fusion of the nucleus of a sperm call with an egg cell nucleus.
how often do ovaries release an egg?
every month
what is the uterus characteristics?
- thick muscular walls, which contract to push baby out during birth.
what are oviducts?
Tubes that transport the eggs from the ovaries to the uterus.
site of fertilisation
what is the vagina?
The baby is pushed down through the vagina during birth
what is the cervix?
- The neck of the womb.
- narrow part at the base of the uterus
- holds developing foetus in place.
what is the function of the sperm ducts?
transport sperm cells from the testes to the urethra
what is the function of the scrotum?
Bag of skin that holds the testes and holds them outside of the body. Healthy sperm need cooler conditions to develop.
what is the function of prostate glands?
produce liquid containing glucose that is added to sperm cells to make semen.
what is the function of the penis?
- contains the urethra, through which semen is transported during intercourse.
what is puberty triggered by?
Hormones released by the brain
what are the sexual characteristics caused by hormones in males?
- voices deepen
- shoulders get broader
- facial hair grows
- pubic hair
what are the sexual characteristics caused by hormones in females?
- breasts develop
- hips widen
- periods start
- pubic hair
what does the hormone FSH do?
tells the ovary to make an egg
what does oestrogen do?
causes the lining of the uterus to thicken and prevents more eggs developing.
what does the hormone LH do?
makes the ovary release an egg
what does progesterone do?
thickens the uterus lining eve more
how long is the menstrual cycle?
around 28 days
where is FSH and LH made?
pituitary gland in the brain
