1.4-1.5 Specialisation In Animal And Plant Cells Flashcards
Describe a sperm cell
Their function is to transport the male DNA to the egg and found in the testes
Its adaptations are
* A long tail to swim to the egg
* Lots of mitochondria to transfer to provide energy from respiration for the sperm to swim long distances
* An acrosome at the front of the head. Stores digestive enzymes breaking down outer layer of egg.
*A large nucleus contains genetic info
Describe a nerve cell
- The function of the nerve cell is to carry nerve impulses around your body found in nervous system
- Nerve endings or synapses pass impulses
- Contain lots of mitochondria to make transmitter chemicals
- The long axon carries nerve impulse
- Dendrites to make connections to other nerve cells
Describe a muscle cell
- The function of muscle cells is to contract and relax to move bones in the skeleton
- Found in the muscles
- Special proteins slide over each other making fibres contract
- Many mitochondria transfer energy
- Store glycogen broken down and used in cellular respiration to transfer energy needed fibres to contract
Describe Root hair cells
- Root hair cells absorb minerals and water from the soil
- increase the surface area for water to move into cell
- Large permanent vacuole speeds up movement
- Mitochondria transfer energy
Photosynthetic cells (palisade cell)
Plants can make their own food by photosynthesis found in top of leaf
Chloroplasts contain chlorophyll that trap light
Positioned in continuous layers to absorb as much light
Large permanent vacuole keeps cell rigid
Describe xylem cells
Transport tissue in plants and carry water and minerals
Special chemical called ligin builds up in spirals in cell walls.
Cells die and form long hollow tubes allow water and mineral ions
Spirals and rings of lignin very strong and help withstand pressure of water to support plant stem
Describe phloem cells
Carry food made by photosynthesis. Made up of phloem cells that form tubes. Dissolved food move up and down and found in stem
Cell walls between the cell break down form special sieve plates.
Allow water carrying dissolved food to move freely up
Lose a lot of their internal structures
Mitochondria transfer energy needed to move dissolved food up and down the plant in phloem
How does a cell become specialized
As an organism develops, cells differentiate to form different types of cells
Most animal cells and plant cells differentiate at an early stage.
In mature animals, cell division is mainly restricted to repair and replacement
As a cell it differentiates it aqquires different sub-cellular structures to enable it to carry out a certain function
Cone cells are specialised nerve cells in the eye. They contain a chemical that changes in coloured light. As a result of the change, an impulse is sent along another nerve cell to the brain. Cone cells usually contain many mitochondria. Suggest why this is an important adaptation.
Transmitter chemicals are required to pass impulse from cone cell to another nerve cell and then on to brain.
The many mitochondria supply energy from cellular respiration needed to make transmitter chemicals.
Describe the features you’d would look for to decide on the function of an unknown specialised animal cell
. number of mitochondria indicates how much energy cell uses
• flagella or cilia – presence indicates whether cell moves around or moves substances such as mucus
• nucleus – presence indicates whether cell is capable of reproduction
• storage materials such as fat or starch – presence indicates whether cell stores materials it can use for respiration
Suggest why a trunk of a tree cannot carry out photosynthesis
Cell not exposed to sunlight and therefore not adapted to photosynthesise (not photosynthetic).
Describe the features you would look for to decide on the function of an unknown specialised plant cell
chloroplasts – presence indicates whether cell is photosynthetic
• large vacuole – presence indicates role in osmosis/rigid support
• lignin spirals – presence indicates strengthening and transport of water
• sieve plates/companion cells – presence indicates transport of dissolved food
• mitochondria – presence indicates active movement of substances.
