Reproduction Flashcards
What are the 8 life processes
- Movement
- Reproduce
- Sensitivity
- Control
- Growth
- Respiration
- Excretion
- Nutrition
Mrs C Gren
What is a life cycle?
Life cycle =
All plants/animals start life small
Over time they grow bigger/ body change
When grown up, they reproduce and create next generation
Next generation will grow bigger and have offspring too…
Definition of Germination
Process of a seed begging to develop into a new plant
(Seed develops)
Definition of Growth
The plan creates news cells to get larger, and grow new organs (leaves)
Definition of Flower production
The plant produces flowers which contain the males and female parts necessary for reproduction
Definition of Pollination
Pollen is delivered to the flower either by an insect/bird or wind
Definition of Seed dispersal
The plant spread their seed to avoid competition between each other.
Seed travels by humans/ wind/ animal
Life cycle of a plant
- Growing plant
- Flower production
- Pollination
4.Dispersal of seed - Germination
- Growing plant…
Life cycle of a human
- Baby
- Child
- Adolescent
- Adult
- Pregnancy
- Baby…
Butterfly metamorphosis/ life cycle
- Egg
- Caterpillar
- Chrysalis
- Butterfly
- Reproduce
- Egg
Life cycle of a frog
- Frog spam
- Tadpoles
- Leg grow
- Froglet
- Adult frog
- Reproduce…
What are the 2 types of reproduction
- Sexual reproduction- which requires 2 parents (male/female). Animals and most plants reproduce that way.
- Asexual reproduction - Only requires 1 parent. The offspring are exact copies. (Bacteria and other small organisms reproduce that way and some plants.)
What happen to the genes during Sexual reproduction?
- Genetic information of male + female are combined
- It creates a new unique organism (with half of the genes from each parent)
- Offspring will be a unique combination of its parents’ genetic information.
What are Gametes
Gametes are the specialised sex cells required for sexual reproduction. They contain half the genetic information necessary to create a new organism.
For reproduction to occur, male and female gamete must be fused.
This process is called FERTILISATION
What are the two types of Fertilisation?
Male fish/frogs fertilise the egg cells outside of the female’s body.
This is called EXTERNAL FERTILISATION.
The egg cells of birds/mammals are fertilised inside of the female’s body. This is called INTERNAL FERTILISATION.
Note: fish/frogs leg lots of eggs; birds a couple. For mammals the young grow in a uterus inside the mother’s body.
Describe human reproduction
Human reproduction involves the fusion of a male gamete with a female gamete during fertilisation, leading to the development of a Zygote, which then develop into a fetus and then a baby.
How do plants reproduce?
Plants reproduce both SEXUALLY through POLLINATION and FETERLISATION and ASEXUALLY through VEGETATIVE PROPAGATION.
Anatomy of a flower
Most flowers have both male and female parts
- Stigma- at the top of the pistil is the stigma which collects the pollen
- Style- pollen is carried through its hollow body called the style
- Stamen- male part of a flower
- Sepal- beneath the petals, there are sepal (leaf like projections)
- Anther- at the topic of the filament, the anther holds the pollen
- Filament- The long stalk of a stamen
- Pistil/carpel- the female part of a flower
- Ovary- is where the pollen fertilises the flower’s egg.
What a male sex cell in a plant is called?
Sperm cell or male gamete
What a female sex cell in a plant is called
Egg cell or Ovum
What are the stages of pollination and fertilisation?
- The anther produces and releases pollen grains.
- Pollen grains are carried on the wind/ or bees
- Pollen lands on the stigma. This is the pollination.
- A pollen tube grows out of the grain into the stigma/ down the style
- The pollen tube joins with the nucleus of the ovule.
- Male sex cells travel down the pollen tube and enter the ovule
- Male sex cells join with the female sex cells. This is called fertilisation.
- The embryo formed form the joining of sex cells grows and a seed is formed.
What is pollination?
Process when pollen is carried from the Stamens to other flowers to pistil via the wind/animal.
What is fertilisation
Process when the male and female cells join.
What are sperm cells?
Male reproductive cell or gamete.
They hold the father’s genetic information.
Their mission = fertilise an egg cell.
What is an egg cell?
Female reproductive cell or gamete. It holds the mother’s genetic information.
It fuses with a sperm cell during fertilisation to form a new organism.
What is adolescence?
The time between childhood and adulthood.
During that time a gland in the brain start to produce extra hormones. These special chemicals make cells grow and divide faster. They make testes and ovaries mature and produce sex hormones.
At PUBERTY the mature testes/ovaries start to release sex cells.
Body parts other than sex organs develop special features (secondary sexual characteristics= e.g. deeper voice, broader shoulder). It’s easier to tell a boy from a girl.
What are the male reproductive organs?
- Testes- make sperm
- Scrotum- holds the testes
- Sperm duct - carries the sperm
- Gland- adds a liquid to the sperm
- Urethra- carries the sperm out of the body
What are the female reproductive organs
- Vagina- receives sperm
- Cervix- a ring of muscle
- Oviduct - carries egg to uterus
- Ovary- makes egg
- Uterus- where the baby grows
How does the menstrual cycle prepare for reproduction?
Menstrual cycle = links the release of an Ovum (egg cell) to the development of the uterus lining.
Each menstrual cycle lasts about 1 month.
Hormones (chemicals) control the menstrual cycle.
If the egg isn’t fertilised, the lining of the uterus breaks down.
The woman has a period. The bleeding is called menstruation.
Key dates of Menstruation
- Lengths of Menstrual cycle = 28 days
- Cycle starts on Day 1
- Egg is released from Ovary = on day 14
What is OVULATION? (in humans)
OVULATION = When female ovaries produce an egg every 28 days.
What is FERTILISATION? (in humans)
FERTILISATION
If sperm meets an egg, the sperm’s nucleus can join with an egg’s nucleus.
The fusing of the nuclei is called FERTILISATION.
How many sperm do males produce during ejaculation?
250 millions
How many eggs do the ovaries normally produce every month?
1
What percentage of the sperm is useless?
99%
What attack the sperms?
White blood cells
How many sperm can get into an egg cell?
1
What is EJACULATION?
EJACULATION
The ejection of sperm through the penis
What is the Implantation?
IMPLANTATION- when the embryo sinks into the uterus lining.
What is the GESTATION?
GESTATION = The time between the FERTILISATION and the BIRTH
e.g. gestation for rabbit= 31 days, 63 days for cats, 267 days for humans, 645 days for elephants, 19 days for mouse.
Pregnancy timeline
Week 2= egg travels the uterus and attaches to the uterine wall
Week 4= Embryo is 1cm
Week 7= Foetus is 1.5cm, it has a heart, brain, limbs, eyes and organs
Week 15= Foetus is 9cm. It has finger nails, eyebrows
Week 18= 20 cm. It can hear noises. You can see gender.
Week 24= Internal organs finished developing. Baby have touch sense.
Week 30= Foetus can tell the difference between light/dark. 39cm.
Week 33= head is moving downward
Week 37= lungs are mature
Week 40= Birth
How does the developing baby survive in the uterus?
The PLACENTA (bag around the embryo) is full of a liquid AMNIOTIC FLUID which support the embryo,
Foetus is kept at a constant temperature in the mother’s body.
The PLACENTA grows in the lining of the uterus. The UMBILICAL CORD joins the foetus to the placenta.
Substances pass across the placenta between the blood of the foetus and the blood of the mother. But both blood do not mix.
The oxygen and foot are transferred from the mother to the foetus. Whilst the waste such as Carbon dioxyde is transferred from the foetus to the mother.
What can harm the baby in the womb?
Alcohol and other drugs can harm the baby.
What is the job of the umbilical cord?
Facilitate the transport of oxygen and nutrients + moving waste products.
What is the job of the amniotic fluid?
Cushioning/ protecting the foetus.
What are the 2 substances that pass across the placenta?
From mother to foetus ==> oxygen + nutrient
From foetus to mother ==> waste + carbon dioxide
How are children born?
Childbirth is called labour.
The baby passes out of the uterus and through the vagina into the outside world.
The uterus muscle (cervix) must relax to open up.
When the baby is ready to be born, contractions of the muscles of the uterus pull the cervix open.
When cervix is open the baby’s head go down the vagina.
Then when out, baby takes first breath
Then finally placenta get out= after birth.
Then it’s important to take care of the baby, keep it clear, warm, with food.
Mammary glands produce milk. Breast milk contain substances that destroy micro organisms that can cause infection.
Type of issues if couple have difficulties conceiving.
- Woman doesn’t release egg cells
- Man produces faulty sperm
- Woman’s fallopian tubes blocked
So people use IVF (In vitro fertilisation) to help the fertilisation of the egg and implantation of the embryo.
Why do you look similar to your parents?
DNA is the genetic information stored in the nucleus. This information determines how the cells acts. (e.g. it define your eye colour, your skin colour…)
Genetic information is bundled into CHROMOSOMES (packages).
CHROMOSOMES definition
Chromosome is a thread like structure within a cell’s nucleus, composed of DNA. It carries generic information in the form of genes.
Chromosomes always come in pairs.
One of each pair come from the mother, and the other one from the father.
How many chromosomes have humans?
23 pairs of chromosomes
46 individual chromosomes in total
What is an INHERITED VARIATION?
Variation is a characteristic that is a result of genetic information from the parents. This is called inherited variation.
Why children looks a little like their father and a little like their mother?
Because they get half of their DNA and inherited features from each parents.
What are environmental causes of variation?
- climate
- diet
- accident
- culture
- lifestyle
Environmental variation are cause by the surrounding (e.g. if you eat too much food, you will become heavier)
