Lesson 3: Cell Specialisation Flashcards
What does it mean if a cell is “specialised?”
- Specialized cells have been differentiated to carry out a particular function.
What are stem cells?
- Stem cells are basic cells with no specialisation that have the potential to change into any type of cell.
How do stem cells change into specialised cells?
- Stem cells change into specialised cells by differentiation.
- This controls the development of the body.
What is a red blood cell’s function?
How is it specialised to carry out this function?
Function: Carry oxygen from lungs to cells and tissues.
Specialisation:
1.) Contains hemoglobin (binds to oxygen)
2.) Prokaryotic so there is space for hemoglobin.
3.) Very flexible to move through narrow vessels.
4.) Biconcave shape: large surface area, for diffusion of oxygen.
What is a nerve cell’s function?
How is it specialised to carry out this function?
Function: Carry electrical impulses.
Specialisation:
1.) Dendrites increase surface area so that other neurons can make contact and form connections.
2.) Long axon–> carry impulse over long distance.
3.) Myelin sheat —> insulates/ speeds up transmission.
4.) Synapses: junctions allow impulses to pass from one neuron to another.
What is a sperm cell’s function?
How is it specialised to carry out this function?
Function: To reach female cell and join with it.
Specialisation:
1.) Acrosome contains enzymes to digest into ovum.
2.) Nucleus with male genetic information.
3.) Mid piece full of mitochondria for energy to swim.
4.) Tail for swimming.
What is a muscle cell’s function?
How is it specialised to carry out this function?
Function: Allows motion
Specialisation:
1.) Muscle cells group together to make a tissue.
2.) Mitochondria provide energy for contraction.
3.) Potein fibres for contraction. i.e. protein fibres shorten when they contract.
What is a root hair cell’s function?
How is it specialised to carry out this function?
Function: To absorb water and minerals by osmois and active transport.
Specialisation:
1.) Root hair has large surface area to collect water and minerals.
2.) A lot of mitochondria to absorb minerals by active transport using carrier proteins.
What is a palisade cell’s function?
How is it specialised to carry out this function?
Function: To absorb sunlight for photosynthesis.
Specialisation:
1.) Chloroplasts: absorb light energy for photosynthesis.
2.) Found in top layer of cross section. Below epidermis. Exposed to sunlight.
What is the function of the xylem?
How is it specialised to carry out this function?
Function: Xylem are dead cells that transport water and mineral ions up plant to stem and leaves.
Specialisation
- Made of hollow tubes (no end walls)
- Strengthened by lignin to give strength to plant (to transfer the water. )
- No internal structures –> water flows more easily.
- Lignin = tough + waterproof
*Lignin = in cell wall. It will block water going in (as it is tough and waterproof) and kill the cell.
What is the function of the phloem?
How is it specialised to carry out this function?
Function: Phloem are living cells that transport dissolved sugar (from photosynthesis) up and down the plant for storage or immediate use.
Specialisation:
- Cells are elongated
- Cell sap moves between cells via pores in seive plates.
What is the function of the ciliated epithelial cell?
How is it specialised to carry out this function?
Function: Pushes and moves mucus from one place to another.
Specialisation:
- Cilia (longated cell membrane) move mucus up the trachea (trapping dirt) and moves egg along the oviduct.
- Many mitochondria in cell for cilia to move.
What is the function of the egg cell?
How is it specialized to carry out this function?
Function: Join with male cell, provide nutrients for new cell formed.
Specialization:
1.) Large: to store a lot of nutrients and proteins for growth.
2.) Contains lots of cytoplasm, packed with nutrients.
What are stomata?
Stomata are tiny holes in epidermis who control water loss/ exchange of gases
How do guard cells work?
- Guard cells gain water in the light by osmosis, causing them to become turgid - opening the stomata.
- In low light, the guard cells lose water and become flaccid. Stomata only close in the dark when no carbon dioxide is needed for photosynthesis (or O₂ out)
