Specialised Cells Flashcards
Describe the three ways in which palisade leaf cells are adapted for photosynthesis.
1) Packed with chloroplasts for photosynthesis, crammed at the top of the cell nearer the light
2) Tall shape means a lot of surface area is exposed for absorbing CO2
3) Thin shape means that loads of them are packed in at the top of the leaf where most of the photosynthesis occurs
Describe what happens to the guard cell when the plant has lots of water.
- The guard cells fill with the water and go plump and turgid.
- This makes the stomata open so gases can be exchanged for photosynthesis.
What happens to the guard cell when the plant is short of water and why?
- They lose water and become flaccid making the stomata close.
- They do this to stop too much water vapour escaping.
What is significant about guard cells being sensitive to light?
It means that they close at night to save water without losing out on photosynthesis and so…
They’re adapted to their function of allowing gas exchange and controlling water loss within a leaf.
Describe the three ways in which red blood cells are adapted to carry oxygen.
1) Concave shape gives a big surface area for absorbing oxygen
2) Packed with haemoglobin (the pigment that absorbs the oxygen)
3) No nucleus to leave even more room for haemoglobins
What are the two main functions of an egg cell?
1) To carry the female DNA
2) To nourish the developing embryo
What happens when a sperm fuses with the egg?
The egg’s membrane instantly changes its structure to stop any more sperm getting in.
What is the sperm cell’s function?
To get the male DNA to the egg cell.
How is the sperm cell adapted to its function?
- Long tail and a streamlined head to help it swim
- A lot of mitochondria in the cell to provide the energy needed.
What do sperm cells have to help them get through the egg cells membrane?
ENZYMES in their heads to digest through the membrane.
