Biology Unit #4

Question 1

Cell membrane

Answer 1

Surrounds and protects the cell; also called the plasma membrane

Question 2

Thing that move in and out of a cell

Answer 2

• Water
• Sugar
• Carbon Dioxide
• Oxygen
• Amino Acids
• Waste

Question 3

Homeostaisis

Answer 3

The process of maintaining balance in a cell’s environment

Question 4

Parts of the Cell Membrane

Answer 4

• Phospholipids
• Cholesterol
• Carbohydrates
• Proteins

Question 4

Selectively Permeable

Answer 4

The membrane allows some molecules to pass and blocks others out

Question 5

Phospholipids

Answer 5

• Most of the membrane is made of this
• Phospholipid bilayer = 2 layers
• Has a polar head and a nonpolar tail

Question 6

Phospholipid Heads

Answer 6

Polar, Hydrophilic - water loving

Question 7

Phospholipid Tails

Answer 7

Nonpolar, Hydrophobic - water fearing

Question 8

Fluid Mosaic Model

Answer 8

Membrane is flexible and made of many parts

Question 9

Cholesterol

Answer 9

Keeps the phospholipids from sticking together so it is easier for molecules to move in and out

Question 10

Carbohydrates

Answer 10

Sugar on the outside of the cell membrane which allows the cell to be identified (part of a glycoprotein)

Question 11

Transport Proteins

Answer 11

Proteins that move molecules in and out of the cell

Question 12

Receptor Proteins

Answer 12

A molecule binds to the protein and helps cells communicate

Question 13

Concentration

Answer 13

The amount of solute mixed in a solvent

Question 14

Diffusion

Answer 14

The movement of particles from high to low concentration (sugar dissolving in tea)

Question 15

Equilibrium

Answer 15

A state where the distribution of molecules is balanced

Question 16

Concentration Gradient

Answer 16

When there isn’t an equal amount of molecules in and out of the cell

Question 17

Facilitated Diffusion

Answer 17

A process where larger molecules are moved in and out of the cell through proteins

Question 18

Osmosis

Answer 18

The diffusion of water that moves down the concentration gradient (water is transported by aquaporins)

Question 19

Isotonic

Answer 19

Equal concentration of solute in and out of the cell

Question 20

Hypotonic

Answer 20

Less solute (more water) outside of the cell so the water moves in

Question 21

Hypertonic

Answer 21

More solute (less water) out of the cell so the water moves out