Cell Transport Across Cell Membranes Notes for Quiz on 4/21
Pinocytosis
"cellular drinking", cells take in fluid and dissolved solutes.
Phagocytosis
"cellular eating", cells take in food.
Sodium/Potassium Pump
3 Na+ out for every 2K+ -used to conduct nerve impulses -creates a membrane potential -charge difference across the membrane
Passive Transport
A process that does not require energy to move molecules from a HIGH to LOW concentration. -Diffusion -Facilitated Diffusion -Osmosis
Bacteria and fungi also have cell walls, but they do/do not contain cellulose.
DO NOT
Food is moved into the cell by...
ENDOCYTOSIS
Wastes are moved out of the cell by...
EXOCYTOSIS
2 types of Bulk Transport
Endocytosis Exocytosis
___________are proteins with carbohydrates attached, they function in cell identification.
Glycoproteins "flags"
Hypotonic solution (Animal Cell)
Lysis = bursting
Isotonic Solution (Animal Cell)
Normal :)
2 types of Endocytosis
Pinocytosis Phagocytosis
Hypertonic Solution (Plant Cell)
Plasmolysis -cell membrane pinches away from cell wall.
Proteins that form channels are called
Protein channels
Protein Pumps
Proteins that work as pumps.
"Gate keeper" of the cell-regulates the flow of materials into and out of cell- _____________.
Selectively permeable.
What is an example of Endocytosis?
White Blood Cells, which are part of the immune system, surround and engulf bacteria by endocytosis.
Proteins that carry ions are called
carrier proteins -they change from to move ions across the membrane.
ALL cells have a ____________ made of ____ and ______.
cell membrane, proteins and lipids
Some cells have cell membranes and
cell walls. ex.) plants, fungi, bacteria.
Sucrose Co-transport
cells have sucrose, but need more to make ATP. -Cell uses energy to pump out H+ to bring in more sucrose.
Plant cells have a cell wall made of
cellulose - which is fiber in our diet.
Cell membrane separates the components of a cell from its _________ - surrounds the cell.
environment.
Hypertonic Solutions contain a
high concentration of solute relative to anoher solution (e.g. the cell's cytoplasm).
Cell membrane helps cells maintain _________ - stable internal balance.
homeostasis
When a cell is placed in an isotonic solution, the water diffuses ____ and ___ of the cell at the same rate.
into and out.
When a cell is placed in a hypotonic solution, the water diffuses ____ the cell, causing the cell to _____ and possibly explode.
into, swell.
Hypotonic Soltuions contain a
low concentration of solute relative to another solution (e.g. the cell's cytoplasm).
Endocytosis and Exocytosis
mechanisms by which very large molecules (such as food and wastes) get into and out of the cell.
When a cell is placed in a hypertonic solution, the water diffuses ___ of the cell, causing the cell to ______.
out, shrivel.
Cell membranes and cell walls are _____ allowing water, carbon dioxide, oxygen and nutrients to pass through easily.
porous.
Isotonic solutions contain the
same concentration of solute as another solution (e.g. the cell's cytoplasm).
Hypertonic Solution (Animal Cell)
shrivels :(
Osmosis
the diffusion of water through a selectively permeable membrane like the cell membrane. -WATER MOVES TO DILUTE THE HIGHER SOLUTE CONCENTRATION
Facilitated Diffusion
the movement of larger molecules like glucose or charged molecules like Na+ that must be helped. -Proteins in the cell membrane form channels for larger molecules to pass through
Active Transport
the movement of molecules from LOW TO HIGH concentration. -REQUIRES ENERGY as molecules must be pumped against the concentration gradient.
Diffusion
the movement of small particles across a selectively permeable membrane like the cell membrane until dynamic equilibrium is reached. -movement is due to intrinsic KE of molecules. -The particles move from HIGH to LOW concentration -Particles move relative their own concentrations only.
Hypotonic solution (Plant Cell)
turgid :)
Isotonic Solution (Plant Cell)
wilting/flacid :(
