Cell Transport

Cell Membrane Structure, Cell Size & Diffusion, Passive Transport, Active Transport

isotonic (concentration of solutes and water in the cell compared to outside; water movement; what is the “balance” called)

equal amounts of solutes and water in the cell and the outside; water will move equally in and out; the cell is in an osmotic balance

hypotonic (concentration of solutes outside; concentration of water outside; water movement)

less solutes outside the cell; more water outside the cell; water will move into the cell

hypertonic (concentration of solutes outside; concentration of water outside; water movement)

more solutes outside; less water outside; water will move out of the cell

cytosis (for what cell; for what solution; effects of it)

animal cells; hypotonic; cell expands, bursts, and dies

turgor pressure (for what cell; for what solution; effects of it)

in plant cells; in hypotonic solution; ideal environment, cytoplasm and vacuole are full

why is turgor pressure ideal? Why does the cell that this occurs in not burst compared to the other cell type?

The plant cell will have enough water to do photosynthesis. Plant cells have a large vacuole and a cell wall that stops the cell from bursting

Plasmolysis (for what cell; for what solution; effects of it)

animal cells; hypertonic; the cell will shrink and die

Wilting (for what cell; for what solution; effects of it)

in plant cells; hypertonic; cytoplasm and vacuole shrinks and COULD die if not watered later

What is the fluid mosaic model?

Model that visualizes the cell membrane’s components

What is selective permeability?

A property in the membrane that allows only certain molecules to pass through it.

What is the name of the double layer of lipids in a cell membrane?

Phospholipid bilayer

What acts as channels for molecules to enter in a cell membrane?

proteins

carbohydrates (where are they; purpose)

attached to proteins on surface; cell recognition and adhesion

What attaches the membrane to the rest of the cell?

cytoskeleton filaments

Where is cholesterol found? Its use?

Found only in animal cells and keeps membrane fluid

What are 5, 6, and 7?

Phosphate head, fatty acid tails, and cholesterol

What are 1, 2, 3, and 4?

Protein, carbohydrates, phospholipid bilayer, and cytoskeleton filament

Are larger or smaller cells more efficient for diffusion? Why?

Smaller, they have a larger surface area to volume ratio

What are the functions of the cell membrane?

To control entry and exit of materials (maintain homeostasis) and to protect and support the cell

The phosphate heads within the lipid bilayer are hydrophobic/hydrophilic, while the fatty acid tails are hydrophilic/hydrophobic. (choose which one)

hydrophilic, hydrophobic

The cell membrane is permeable/impermeable to small, nonpolar/polar molecules and permeable/impermeable to larger, polar/nonpolar molecules and ions.(choose which one)

permeable, nonpolar, impermeable, polar

The movement of molecules from an area of higher concentration to an area of lower concentration is called:

simple diffusion

The movement of materials through membrane proteins from an area of higher concentration to an area of lower concentration is called:

facilitated diffusion

The diffusion of water from an area of higher water concentration to an area of lower concentration is called:

osmosis

The substance that dissolves to make a solution is called the:

solvent

Glucose enters cells most rapidly by:

facilitated diffusion

Gases like oxygen and carbon dioxide move across cell membranes using:

simple diffusion

What is active transport?

Uses energy (ATP) and moves molecules against the concentration gradient

endocytosis (what it is; what occurs; how it occurs)

form of active transport; movement of large particles into cell; membrane pinches in and forms a vesicle around the material

phagocytosis (what form of active transport; for what materials; how does it do it)

for endocytosis; “cell eating” for solid materials; cell engulfs large particles

pinocytosis (what form of active transport; for what materials; how does it do it)

for endocytosis; “cell drinking” for liquid materials; cell takes in dissolved molecules as a vesicle

Exocytosis (What is it; what occurs; how does it occur)

Form of active transport; moves large particles out of the cell; vesicle attaches to membrane and empties its contents

What is this diagram representing? What is A, B, C, D, and E?

Active transport through carrier proteins. Amino acids, concentration gradient, carrier protein, phospholipid bilayer, and ATP (energy)

What is this diagram representing? What is H, D, K?

pinocytosis. Dissolved particles, phospholipid bilayer, and vesicle

What is the sodium-potassium pump?

A transport protein used in active transport

What is passive transport?

the movement of molecules into and out of cells, using no energy (ATP), goes with the concentration gradient (high-low), and molecules move to reach equilibrium

What is equilibrium?

A state where solutes are evenly distributed between a cell and the outside of it, but particles still move back and forth across a membrane, just equally

What is facilitated diffusion? (define; what molecules use it)

Diffusion (passive transport) using carrier/transport proteins; carbohydrates and amino acids are transported this way

What is (simple) diffusion?

the net movement of molecules from an area of a higher concentration to an area of a lower concentration

transport proteins

channels for nutrients to enter and wastes to leave

receptor proteins

bind to extracellular substances

recognition proteins

identify cells/substances

adhesion proteins

stick to other cells

Active transport through transport proteins involves the use of ATP  energy made in the ____

mitochondria

Process by which a cell expels waste from a vacuole

exocytosis

Process by which a cell takes in liquids

pinocytosis

form of passive transport that uses proteins

facilitated diffusion

During ________ carrier proteins move glucose molecules across the membrane from areas of higher concentration to areas of lower concentration

facilitated diffusion

______ moves oxygen and carbon dioxide molecules across a membrane from a high concentration to a low concentration

diffusion (simple)