cell biology Flashcards
what does a plant cell contain that an animal cell does not
cell wall - made from cellulose which strengthens the cell preventing it from bursting
chloroplast - contains chlorophyll and site of photosynthesis
permanent vacuole - filled with cell sap, helps give plant its shape
what does an animal cell contain
ribosomes
nucleus
cytoplasm
mitochondria
cell membrane
what is the function of ribosomes
site of protein synthesis
what is the function of nucleus
contains genetic material (DNA)
what is the function of cytoplasm
chemical reactions take place and respiration
what is the function of mitochondria
where aerobic respiration takes place
what is the function of cell membrane
controls what enters and exits the cell
how to calculate order of magnitude
x10 is 1, x100 is 2…
each 10x more is another 1
(Count the zeros)
which of the 2 has the genetic material enclosed in the nucleus
eukaryotic
what is smaller e or p
prokaryotic
how is the genetic material held in a prokaryotic cell then
single loop of dna and plasmids which are small circular strands of dna
what do we call it when a cell becomes specialised
differentiation
adaptation of a sperm cell (animal cell)
long tail, streamlined, packed with mitochondria providing energy for swimming
adaptation of a nerve cell (animal cell)
axon contains myelin which speeds up the transmission of nerve impulses.
end of axon has synapses allowing impulses to pass from nerve cell to nerve cell
dendrites increase surface area so nerve cells can connect more easily
muscle cell adaptation (animal cell)
protein fibres can change their length
protein fibres can shorten for contraction
packed with mitochondria for energy for contraction
root hair cells (plant cell specialisation)
hairs increase surface areaso can absorb water and minerals more effectively
xylem cells (plant cell)
carry water and minerals from root to leaves
what does the phloem do (plant cell)
carries dissolved sugars up and down plant
why don’t root hair cells contain chloroplast
because they are underground so don’t get light from the sun which is needed for photosynthesis
what and why does xylem have thick walls
contains lignin which provides support
what happens to xylem cells because of lignin
and what else makes flow easier
sealed with lignin causing it to die, end walls between cells have broken down, this means a long tube is formed so water and minerals can flow easily
and no internal structures
what are the pores on the end walls of phloem called what is the function
sieve plates allowing dissolved sugars to move through cell interior
each vessel has a … cell connected by …
companion, pores
why does the ploem have a companion cell
to allow dissolved sugars to move through interior of the cell because no nucleus and limited cytoplasm so little mitochondria, mitochondria provides vessel cell with energy
