B1 Cell Structure And Transport Flashcards
Nucleus
Controls activities of the cell
Contains the genetic information of the cell
Cytoplasm
Where most of the chemical reactions take place
Cell membrane
Controls what goes in and out of the cell
Mitochondria
Where aerobic respiration takes place.
Releases energy for the cell
Ribosomes
Where protein synthesis takes place
Cell wall
Made of cellulose
Strengthens and supports the cell
Chloroplasts
They are green and contain a green substance called chlorophyll
It is the site of photosynthesis
Chlorophyll
Absorbs light so the plant can make food by photosynthesis
Permanent vacuole
Filled with cell sap
Keeps cells rigid and supports the plant
Eukaryotic cells
Animal and plant cells
Have genetic material that is enclosed in a nucleus
Prokaryotic cells
Bacterial cells
Do not have genetic information enclosed in a nucleus
Prokaryotic cells contain
Genetic material is a single loop of DNA found free in the cytoplasm
Plasmids
Extra small rings of DNA
Flagella
Helps the bacteria to move around
Slime coat
A protective coat around the bacterial cell
Nerve cells
Specialised cells which carry electrical impulses around the body of an animal
Adaptations of nerve cells
Lots of dendrites to make connections to other nerve cells
An axon which carries nerve impulse from one place to another
Synapses which pass impulses to another cell using special transmitter chemicals
Muscle cells
Specialised cells which can contract and relax
Specialised cells
Differentiated cells which carry out a particular function
Muscle cell adaptations
Special proteins that slide over each other making fibres contract
Contains lots of mitochondria to transfer energy needed for cells to contract and relax
Can store glycogen which mitochondria can use to transfer energy
Sperm cells
Contain genetic info from male parent
Fertilise the egg
Sperm cell adaptations
Long tail to help the sperm move
Lots of mitochondria which transfer energy needed for tail to work
Acrosome which stores digestive enzymes needed for breaking the outer layers of the egg
Nucleus which contains genetic info to be passed on
Root hair cells
Help the plant take up water and mineral ions efficiently
Root hair cell adaptations
Increase surface area
Large permanent vacuole speeds up osmosis
Mitochondria to transfer energy needed for active transport
Xylem cells
Transport tissue in plants that carries water and mineral ions from roots to the highest leaves and shoots
Xylem adaptations
Cells die to form hollow tubes to allow water and mineral ions to move easily through them
Spirals and rings of lignin make them strong and help them withstand the pressure of water moving up the plant
Phloem cells
Carries food made by photosynthesis around the plant
Phloem adaptations
Cell walls break down to form sieve plates.
Allows water carrying dissolved food to move freely up and down tubes
Mitochondria of the companion cells transfer the energy needed to move dissolved foods up and down the plant in phloem
Diffusion
Net movement of particles from an area of high concentration to an area of low concentration
Factors affecting rate of diffusion
Conc difference
Temperature
Surface area
Osmosis
Movement of water from a dilute to a more concentrated solution through a partially permeable membrane
Isotonic
Conc of solution outside the cell is the same as the internal conc
Hypertonic
Conc of solutes in solution outside the cell is higher than the internal concentration
Hypotonic
Conc of solutes is lower outside the cell than the internal conc
Active transport
Movement of cells from an area of low concentration to an area of high concentration
What is needed for active transport
Energy
Where is the energy for active transport produced
Cellular respiration
When does the ratio of surface area to volume fall?
When the object gets bigger
Adaptations for exchanging materials
Large surface area
Short diffusion path / thin membrane
Efficient blood supply
Being ventilated
Culturing microorganisms on an agar gel plate
Hot sterilised agar jelly is poured into a sterilised petri dish, which is left to cool and set
Inoculating loops are dipped in a solution of the microorganism and spread over the agar jelly evenly
A lid is taped on and the plate is incubated for a few so the microorganisms can grow (stored upside down)
