Buscar
Estás en modo de exploración. debe iniciar sesión para usar MEMORY

   Inicia sesión para empezar

level: Level 1 of Transport Across Membranes

Questions and Answers List

level questions: Level 1 of Transport Across Membranes

QuestionAnswer
What 2 types of molecules are plasma membranes made of?protein and phospholipids
What term describes the head of a phospholipid in terms of it's reaction to water?hydrophilic (water loving)
What term describes the tail of a phospholipid in terms of it's reaction to water?hydrophobic (water hating)
Name the area inside a cellintracellular
Name the area inside a cellextracellular
A cell membrane is selectively permeable, what does it select based on?size
Selectively permeable meaningit allows some molecules to pass from one side to the other while other molecule are unable to pass through it
examples of molecules that move by diffusioncarbon dioxide, oxygen, glucose
examples of molecules that don't pass through an SPM by diffusionfood, protein, starch
What is a bilayer?a double layer of closely packed atoms or molecules
Fluid Mosaicdescribes how a cell membrane looks and functions
test for glucosebenedict's reagent turns brick red
Why do cells have a membrane?so they can have different intracellular conditions from extracellular conditions
Why transport? (in green plant cells)they need to photosynthesise so they require carbon dioxide to enter the cell
passive transporthigh to low concentration, does not require energy
active transportlow to high concentration, does require energy
passive transport examplesdiffusion and osmosis
diffusionthe movement of particles from an area of high concentration to an area of low concentration until evenly spread
result of diffusioneven distribution of that type of particle
osmosisthe movement of water from an area of high water concentration to an area of low water concentration through a selectively permeable membrane
When is a cell fully turgid?in water
fully turgidlarge vacuole, cell membrane pushed against cell wall, cell wall prevents cell from bursting
When is a cell plasmolysed?in a salt solution (in a concentrated solution)
plasmolysedsmall vacuole, cell membrane shrunken away from cell wall, cell wall prevents collapse
How is tissue described when lots of cells are plasmolysed?flaccid
What happens to a red blood cell in water?water would enter the cell by osmosis, it would swell up then burst
hypertonica solution which effectively has a LWC because there is a lot of solute dissolved in it
hypotonica solution which effectively has a HWC because there is very little solute dissolved in it
isotonicrefers to two solutions having the same water concentration
What are the terms hypertonic, hypotonic and isotonic used for?to compare water concentrations of fluids on either side of an SPM
solutethe thing that gets dissolved
solventwhat the solute gets dissolved in - the liquid that does the dissolving
solutionthe product of a solute dissolving in a solvent
Why does amoeba not burst?it has a contractile vacuole which sucks up the water and squirts it back out
Where does the energy needed for active transport come from?the ATP - which comes from respiration