Cell transport quiz Flashcards
Why are cells so tiny?
- When the surface area is greater than volume, there is more plasma membrane relative to the inside of the cell.
- materials can be transported efficently
Phospholipid bilayer
2 layers of phospholipids
Phospholipids
a lipid, containing a phosphate group in its molecule
Cholesterol
Inserts itself into the phospholipid bilayer
Regulates the fluidity of the cell membrane
GlycoPROTEIN
Cell-Cell Recognition-
They enable cells to recognize another cell as familiar or foreign, which is called cell-cell recognition.
Cell Adhesion-
They also help cells attach to and bind other cells
GlycoLIPIDS (carbohydrates)
Help maintain stability in the cell
Receptor proteins
Helps with communication between the cell and the extracellular environment by transmitting information into the cytoplasm.
Enzymatic proteins
Proteins that carry out chemical reactions. They transform molecules into new substances, break large molecules down into smaller parts, or build larger molecules from smaller parts.
Intercellular joining proteins
Intercellular junctions are specialized regions of contact between the plasma membranes of adjacent cells. They are essential to any multicellular organism, providing the structural means by which groups of cells can adhere and interact
Attachment PROTEINS
PROTEINS that attach to the extracellular matrix and cytoskeleton. They help SUPPORT the membrane and can coordinate external and internal changes
Channel proteins
like a bead in the membrane, a channel that allows transport into or out of the cell of molecules that can fit through the channel. DOES NOT CHANGE SHAPE
Carrier proteins
Helps move solutes across the membrane. CHANGES SHAPE
Sodium Potassium Pump
Pumping Na+ (sodium ions) out and K+ (potassium ions) in against strong concentration gradients.
Phosphate head
HydroPHILIC (loves/tolerates water)
Fatty acid (lipid) tail
HydroPHOBIC (hates water)
Phagocytosis
Used to engulf large particles such as food, bacteria, etc. into vesicles (cell eating)
Receptor mediated endocytosis
Some integral proteins have receptors on their surface to recognize & take in hormones, cholesterol, etc.
Pinocytosis
Most common form of endocytosis. Takes in dissolved molecules as a vesicle.
Endocytosis
Large molecules move materials into the cell using one of three forms of ENDOCYTOSIS
Exocytosis
The opposite of endocytosis. Large molecules that are manufactured in the cell are released throug the cell membrane
Isotonic
No net movement, the cell is at equilibrium
Hypertonic
The water movement is from the INSIDE to the OUTSIDE of the cell
Hypotonic
Movement of water is from the outside of the cell to the inside of the cell
Plasmolysis
Hypertonic Solution (Shrinks)
CytOlysis
HypOtonic Solution
Passive vs. active transport
Passive: Does NOT require energy
Active: DOES REQUIRE energy
Simple diffusion
Requires NO energy
Molecules move from area of HIGH to LOW concentration
Facilitated diffusion
Molecules will naturally move through the pores in Channel Proteins. Some Carrier proteins do not extend through the membrane. They bond and drag molecules through the lipid bilayer, releasing them on the opposite side.
Osmosis
Diffusion of water across a membrane
Moves from HIGH water potential (low solute) to LOW water potential (high solute)
Concentration GRADient
GRADual difference in the concentration of a dissolved substance
Water potential (high and low)
HIGH water potentional: LOW solute
LOW water potential: HIGH solute
What are aquaporins?
Water channels/ protein pores used during OSMOSIS
What is homeostasis and how is cell transport related to this process?
Balanced internal condition of cells (Equilibrium). This is maintained by the plasma mebrane
Why is the cell membrane selectively permeable?
The polar heads and nonpolar tails makes the membrane selective
Cell membrane
Is flexible and allows a UNICELLULAR organism to move
IMPORTANT NOTES:
Look at the diagrams in Mrs. Agins slides. You got this, keep going!
