CYTOPLASM contains ENZYMES that control the CHEMICAL REACTIONS.
What is the function of the cell wall?
support and strengthen the plant cell
to produce proteins
where photosynthesis takes place
What is the green substance in chloroplasts?
chlorophyll
cellulose
enzymes
mitochondria
What does the permanent vacuole contain?
cell sap (weak solution of sugars and salts)
This is a bacteria cell
Features of a bacteria cell
nucleus
cytoplasm
cell membrane
plasmid DNA
cell wall
vacuole
chloroplasts
flagella
chromosomal DNA (carries most of the genetic information)
Yeast cells do not contain ribosomes or mitochondria
Both yeast and bacteria are single celled organisms
Diffusion is the spreading of particles from a LOW concentration to a HIGH concentration
Diffusion only happens in liquids
The BIGGER the DIFFERENCE IN CONCENTRATION the FASTER the diffusion rate
Dissolved substances can move in and out of cells by DIFFUSION. This is called OSMOSIS
Osmosis is the movement of water from a less concentrated solution to a more concentrated solution through a partially permeable membrane.
Particles move about randomly, so they move both ways through a semi permeable mebrane in osmosis. This means there is a NET (overall) movement FROM the HIGHER concentration
Adaptions of the PALISADE CELL or PHOTOSYNTHESIS
Packed with chloroplasts
More chloroplasts near the top of the cell so they're nearer the light
TALL meaning larger SURFACE AREA for ABSORBING CO2 from the air
THIN meaning they can be crammed tightly next to eachother at the top of the leaf
Special kidney-shape
When the plant has lots of water, the cells become TURGID so the stomata OPEN and gases can be exchanged
When the plant is short of water, the cells become FLACCID, making the stomata close, meaning less water vapour escapes.
THIN outer walls and THICKER inner walls make the opening and closing work
SENSITIVE TO LIGHT - CLOSE AT NIGHT to save water
Adaptions of the GUARD CELLS to OPEN and CLOSE PORES (STOMATA)
Guard cells are grouped together at the top of the leaf where most of the photosynthesis happens
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