cell biology Flashcards
(23 cards)
what are phospholipids
they are a double lair(bilayer) that allows the absorption of material into the cell
what does the phospholipid bilayer allow to pass through the cell membrane (3)
oxygen, carbon dioxide and glucose
why are molecules like startch and fat unable to pass through the phospholipid bilayer
they are to big to pass through
what is the function of the cell membrane
it controls what enters and exists the cell
state the feature of the phospholipid bilayer that allows materials to pass through
it is selectively permeable
name the two molecules found in the cell membrane
phospholipids and proteins
what is the molcule that makes up the double layer in the cell membrane
phospholipids
name two substances that can pass through the phospholipid bilayer and enter the cell and why
oxygen and glucose because they are small enough to die through the selectively permeable membrane
what is the description of passive transport
transport that’s does not require energy to move molecules across the membrane
what is the description of active transport
transport that requires energy to move molecules across the membrane
what is two examples of a passive transport
diffusion and osmosis
where does passive transport take place
it occurs down the concentration gradient and does not require energy
what is the definition of diffusion
diffusion is the movement of molecules down the concentration gradient from a higher concentration to a lower concentration
what type of process is diffusion
passive process
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what is an example of substances that get removed from the cell during diffusion
carbon dioxide
when do the molecules stop moving during diffusion
when the concentration gradient of the same
where does diffusion take place in the body (2)
alecvoli and capillary’s
describe the diffusion process of diffusion in the alveoli
oxygen diffuses into the blood in the blood capillary from the alveoli in the lung. carbon dioxide diffuses out
what is ment by the concentration
why is diffusion a passive process
it does not require energy to move molecules across the membrane
what type of process is osmosis
passive transport
what is osmosis
osmosis is the movement of water molecules from a higher water concentration to a lower concentration through a selectively permeable membrane
