B1 Flashcards
calculation for magnification
I = A x M
Image = mm
Actual = micrometers
Magnification = X
Cell membrane function
barrier: controls what goes into the cell
Nucleus function
controls the cell
cytoplasm function
where chemical reactions take place
mitochondria function
where respiration takes place
ribosome function
produces protein for the cell
chloroplast function
to carry out photosynthesis
vacuole function
keeps the shape of the cell, storage
cell wall function
provides support for the cell
what is the main difference between eukaryotic and prokaryotic cells?
eukaryotic cells have a nucleus, prokaryotic cells do not
what cells are eukaryotic
plant cells and animal cells
what cells are prokaryotic?
bacteria cells
list some features exclusive to prokaryotic cells
slime capsule,
flagella,
plasmids,
what is a specialised cell
a cell that is adapted to perform an specific job
root hair cell function
absorb water and minerals from soil
list some features of root hair cells
large surface area to absorb more water.
the only plant cells without a chloroplast
what is diffusion
the process of particles moving down the concentration grade from an area of high concentration to an area of low concentration. this is a passive process
what factors can increase the rate of diffusion?
temperature.
size of particles.
distance of diffusion.
what is osmosis
the movement of water particles from an area of high concentration to an area of low concentration through a partially permeable membrane. passive process.
explain the term partially permeable
a membrane that is permeable to the small molecules of water, but does not allow large solute molecules to permeate
define the term validity
the extent to which a measurement or study measures what it purports to measure
what is the equation for %change
final / initial x 100
what is active transport
the movement of minerals against the concentration gradient from an area of low concentration to an area of high concentration using energy
why does active transport require energy?
it is working against the concentration gradient and needs energy to rotate the protein transporting the solute.
the chemical that the cell wall is made of
cellulose
in which type of animal cell would you find a lot of mitochondria
muscle cells, because they are more mobile and need more energy
resolution definition
a measure of the ability to distinguish between two separate points that are very close together
how many micrometers in 1mm
1000 micrometers
how many nanometers in 1 micrometer
1000 nanometers
features that eukaryotic and prokaryotic cells SHARE
genetic material, cytoplasm & cell membrane
features that make sperm cells specialised
long tale to swim to egg. enzymes in the head of the sperm to penetrate the egg.
how are nerve cells adapted?
it has lots of dendrites to make connections to other nerve cells
how are muscle cells adapted?
contains special proteins that slide over each other, making the fibres contract.
equation for rate of reaction
rate = 1/t - time taken
equation for percentage change
100 x (change in mass/ initial mass)
in what cell would you find a lot of mitochondria? why?
muscle cells, because they require a lot of energy, so they need to respire more
describe how water moves from roots to the leaves
by transpiration stream in xylem
