cells Flashcards
5 parts of an animal cell and there purposes?
nucleus: contains genetic information and controls activities of cell
cytoplasm: gel-like substance where most of the chemical reactions happen,it contains enzymes which control these reactions
cell membrane: hold cell together ad controls what goes goes in and out
mitochondria: where most of the reactions for respiration take place. It releases energy.
ribosomes: where proteins are made
3 extra parts of a plant and purposes?
cell wall: made of cellulose to support/strengthen the cell
vacuole: contains cell sap, a weak solution of sugar and salts
chloroplasts: where photosynthesis happens which makes food for the plant. They contain a green substance called chlorophyll
4 parts of a yeast cell?
nucleus,cytoplasm, cell membrane, cell wall
4 parts of a bacterial cell
genetic material, cytoplasm,cell wall and cell membrane
where does the genetic information go in a bacterial cell?
in the cytoplasm
what’s diffusion?
spreading out of particles from an are of high concentration to an area of low concentration
what states(gas,liquids, solids etc) does diffusion happen in?
solutions and gases
the bigger the difference in concentration..
the faster the diffusion rate
which molecules can diffuse through cells?examples
small eg oxygen,glucose,amino acids, water
which cant diffuse through membrane?
big eg. starch
how are palisade leaf cells adapted for photosynthesis
packed with chlorophyll
why are the chlorophyll crammed at the top?
so they are nearer the light
why is it good that the palisade leaf has a tall shape?
a lot of surface area exposed down the side for absorbing CO2
why is it good that the palisade leaf has a thin shape?
you can pack loads of them in at the top of the leaf
what are guard cells adapted for?
opening/closing pores(stomato)
what makes the stomata open?
when the plant has lots of water the guard cells fill with it and it goes plump and turgid.
what makes the stomata close?
when there is a shortage of water the guard cell becomes flaccid making it close
why is it good the pores open?
gases can be exchanged for photosynthesis
why is it good the pores close?
stops too much water vapor escaping
what makes the opening and closing work
thin outer walls and thickened inner walls
what are they sensitive to?what does this means happens?
light-close at night to save water without losing out on photosynthesis
what are red blood cells adapted to do?
carry oxygen
why is it good it has a concave shape?
large surface area for absorbing oxygen and helps them pass smoothly though capillaries to reach blood cells
what are they packed with?
haemoglobin-pigment that absorbs oxygen
what don’t they have?why?
nucleus so there is more room for haemoglobin
what are sperm and egg specialised for?
reproduction
main functions of egg cell?
carry female dna and to nourish the developing embryo
when a sperm fuses with an egg what happens?
the eggs membrane changes its structure to stop anymore sperm getting in
function of sperm?
get the male dna to the female dna.
how is the sperm adapted?(2)
- long tail and streamlined head to help it swim to the egg
- lot of mitochondria in the cell to provide energy
what are large multicellular organisms made up of?
organ systems
what is differentation
the process by which cells become specialised for a particular job
when does differentiation occur
during the development of a multicellular organism
example of a multicellular organism
squirrel
three tissues in mammals?+jobs
muscular-contracts to move what its attatched to
glandular- makes and secretes chemicals like enzymes and hormones
epithelial- covers parts of the body
tissues in the stomach and their job
muscular: moves stomach wall to churn food
glandular: makes digestive juices to digest food
epithelial: covers outside and inside of the stomach
organs and jobs in the digestive system(6)
- glands(pancreas,salivary glands) which produce digestive juices
- stomach:digest food
- small intestine: digest food
- liver:produces bile
- small intestine:absorbs soluble food molecules
- large intestine: absorbs water from undigested food leaving faeces
three tissues in a plant and job
mesophyll:most of photosynthesis occurs
xylem+phloem:transport things like water,mireal ions and sucrose around the plant
epidermal:covers whole plant
