Reproduction Flashcards
What is the difference between asexual reproduction and sexual reproduction?
- Asexual reproduction involves mitosis to produce genetically identical copies
- Sexual reproduction involves the combination of sperm and egg cells to create a zygote
What is the difference between a zygote and an embryo?
The zygote is the diploid cell formed from the fusion of a sperm and egg cell, it becomes an embryo after it begins to divide.
Give one advantage and one disadvantage of sexual reproduction
Advantage - It introduces variation.
Disadvantage - It is slower and produces a limited amount of offspring.
Give one advantage and one disadvantage of asexual reproduction
Advantage - It produces lots of offspring quickly
Disadvantage - It does not introduce variation and so all offspring are susceptible to the same environmental pressures as the parents.
State 3 features of insect pollinated plants
- Bright coloured flowers
- Sweet netcar
- Sticky pollen
State 3 features of wind pollinated plants
- No bright colours
- Stigma exposed to the air
- Light pollen
Describe the process of fertilisation in plants
- Pollen grain lands on the stigma
- Pollen tube begins to grow from the pollen grain into the ovary
- Pollen grain travels down the pollen tube and fertilizes the egg
- Fruit and seeds form from the egg
How can seeds grow before they can photosynthesise?
They use energy stores of starch
Give one natural example of plant cloning
Plant runners from strawberries and spider plants.
Give one artificial example of plant cloning
Tissue cuttings placed in a growth medium.
What does oestrogen do?
Oestrogen causes the uterus lining to thicken.
Where is oestrogen secreted from?
The ovaries
What hormone does oestrogen inhibit?
Oestrogen inhibits follicle stimulating hormone (FSH).
What does progesterone do?
Progesterone maintains the womb lining.
Where is progesterone secreted from?
The ovaries
