CELL TRANSPORT TEST Flashcards
Lord save me this is tommarow (33 cards)
Why are cells so tiny?
To maximize area:volume ratio.
(EXAMPLE: 6:1 VS 2:1)
Phospholipid Bilayer
2 Layers of Phospholipids
Intracellular = Tails
Extracellular = Heads
Phospholipids
Head = Polar (Hydrophilic)
Tail = Nonpolar (Hydrophobic)
Cholesterol
Regulates the fluidity of the cell membrane
GlycoPROTEINS
Sticks onto the PROTEINS
- Cell-Cell Recognition
- Cell Adhesion
GlycoLIPIDS
Sticks onto the LIPIDS
Binds to carbohydrate receptors on cells.
Receptor Proteins
They help with communication between the cell and the extracellular environment by transmitting information into the cytoplasm. (Receptor = Receptionist)
Enzymatic Proteins
Carries out chemical reactions.
Think if 8th grade science chemical reactions: transform molecules into new substances, break large molecules, or build larger molecules.
Intercellular joining proteins
Membrane proteins that form intercellular junctions that attach adjacent cells. (Looks like two medicine pills attached to each other)
Attachment Proteins
Proteins that attach to the extracellular matrix and cytoskeleton to support the membrane and can coordinate external and internal changes.
Channel & Carrier Proteins
Channel: Embedded in the cell membrane & have a pore for materials to cross
Carrier: Changes shape to move material from one side of the membrane to the other.(CARRIES TO THE OTHER SIDE)
Sodium Potassium Pump
Open on intracellular side then after sodium binds to pump, changes side to push sodium onto the extracellular site, to let potassium ions to bind, and cycle repeats.
Why are proteins are crucial to membrane function and cell transport?
To serve as specific receptors, enzymes, and transport proteins.
Phosphate head
Polar and Hydrophillic
Fatty acid (LIPID) tail
Non-polar and Hydrophobic
Why is the cell membrane selectively permeable?
To only let certain things in, and certain things out.
Active Transport (REQUIRES ENERGY)
Exocytosis, Endocytosis, and Sodium-potassium pump (EES)
Passive Transport (NO ENERGY NEEDED)
Osmosis, diffusion, and facilitated diffusion
Simple Diffusion
Doesn’t require energy
High-Low concentration
Facilitated Diffusion
Doesn’t require energy
Uses TRANSPORT proteins to move high to low concentration
Osmosis
Diffusion of water across a membrane.
Moves from HIGH water potential (low solute) to LOW water potential (high solute)
Concentration Gradient
The gradual (GRADIENT = GRADUAL) difference in concentration of a dissolved substance in a solution from high to low water concentration.
Water potential (high and low)
High H2O potential = Low solute concentration
Low H2O potential =
High solute concentration
What are aquaporins?
Water Channels
Protein pores used during OSMOSIS