Reproduction Flashcards
State the difference between adolescence and puberty
The period of time when a person develops from a child to an adult is known as adolescence. The physical changes that take place are known as puberty
Describe the main changes that take place during puberty
Girls develop breasts and start their periods. Boys develop a deeper voice and facial hair will start to appear.
Describe the main structures in the male reproductive system
Male structures :
-Sperm ducts - muscular ducts about 30cm long.
- Glands- small structures near the uretha.
- Urethra- tube in penis.
- Penis- sex organ, cylindrical in shape.
- Testis- oval organs in the scrotum.
- Scrotum- bag of skin containing the testis.
Describe the main structures of the female reproductive system
Female structures:
- Oviduct-tube connecting ovary and the uterus.
- Ovaries-pair of small ,oval shaped glands, either side of the uterus.
- Uterus- hollow, pear shaped organ.
- Cervix- ring of muscle at the entrance to the uterus.
- Vagina- muscular canal ending at the cervix.
- Uretha- tube from bladder.
Describe the function of the main structures in the male reproductive system
Male function:
- Sperm duct-these are tubes that carry sperm from the testis to the penis.
- glands-they produce nutrients that help to keep the sperm alive. The mixture of sperm and fluid - semen.
- uretha- a tube that carries urine from the bladder out of the body.
- penis- inserts sperm into female.
- testis- produce sperm and male sex hormones.
- scrotum- keeps the temperature of the testis slightly lower than the rest of the body.
Describe the function of the main structures in the female reproductive system
Female function:
- Oviduct- carries the egg to the uterus.
- ovaries- store and egg release,
- uterus- where a fetus /baby develops until birth.
- cervix- keeps the fetus/ baby in place.
- vagina- receives the sperm during sexual intercourse.
- uretha- carries urine out of the body.
Describe the structure and function of gametes
Structure:
It is microscopic, consists of a head, a neck, a middle piece, and a tail.
Function:
Reproductive cells
Describe the process of fertilisation
1-Fertilisation is the joining together of a sperm and an egg.
2-The sperms swim through the cervix , up the uterus and into the egg tube to find the egg.
3-This is a very long way for the sperms to swim and most of them will not reach the egg.
4-To overcome these loses millions of sperms are released into the vagina at once.
5-A number of sperms may reach the egg but only one is able to enter it .
6- This is because the egg makes a skin around itself tii ok stop other sperms from entering.
7- The egg can live for about a day and a sperm can live for up to 3 days.
8- so there are only about 3 days in a month when it is possible for the egg to be fertilised.
Describe what happens during gestation
A fetus develops in the uterus. This is known as gestation. The fluid sac protects the fetus from bumps. The fetus is attached to the placenta by the umbilical cord. Substances transfer between the mother and baby through their blood in the placenta. After 40 weeks the baby is ready to be born.
Describe what happens during birth
During childbirth, the muscles at the top of your uterus press down on the baby’s bottom. Your baby’s head then presses on your cervix which, along with the release of the hormone oxytocin which brings on contractions.
State what the menstrual cycle is
The female reproductive system works in a cycle called the menstrual . An egg is released each month . If the egg is not fertilised the. The lining of the uterus breaks down and leaves the body through the vagina. This is called a period.
Identify the main structures of a flower
Sepal- protects the flower bud.
Petal- attracts insects.
Filament- holds the anther up.
Anther- makes the pollen.
Stigma- sticky platform for pollen to attach to.
Style- holds the stigma above the ovary.
Ovary- contains the egg cell.
Describe the process of pollination
1- a bee visits a flower to feed on nectar. The bee wriggles deep into the flower past the anthers.
2- as the bee passes the anthers, pollen grains stick to the hair on the bees body .
3- the bee flies to another flower, carrying pollen from the first flower with it .
4- the bee feeds on the nectar in the second flower.
5- pollen grains from the bee get stuck in the sticky stigma .
6- a pollen grain develops a pollen tube that grows down the style to the ovule.
7- the pollen grain nucleus joins with the egg nucleus.
8- the fertilised egg develops into a seed.
Describe the differences between wind pollination and insect pollinated plants .
Unlike insect pollinated plants, wind pollinated plants are not scented, because there is no need to attract insects with scent. Unlike insect pollinated plants, wind pollinated plants offer no nectar (nectar is an important food reward for bees and other pollinating insects)
Describe the process of fertilisation in plants
In plants, fertilization is a process of sexual reproduction, which occurs after pollination and germination. Fertilization can be defined as the fusion of the male gametes (pollen) with the female gametes (ovum) to form a diploid zygote. It is a physicochemical process which occurs after the pollination of the carpel
