Bio - Transport, Water, pH

What does selective permeable mean?

When only certain things can enter/or it chooses things to enter

Circular “head” in the phospholipid bilayer

Phosphate group

Squiggly “tails” in phospholipid bilayer

Fatty acid tails

Hexagon shaped molecules

Cholesterol

Polar and hydrophilic part of plasma membrane

Phosphate groups (like water)

Non-polar, hydrophobic part of plasma membrane

Fatty acid tails (hate water)

Active transport

Requires energy from the cell (Na/k pump) from low to high concentration

Passive transport

Doesn’t require energy (diffusion) from high to low concentration

Diffusion

When particles move from high concentration to low concentration naturally

Osmosis

Diffusion of water across a selective permeable membrane (water will always move until it is equal on both sides)

Isotonic

Equal percent solute in and out of the cell (stay) water goes in and out of the cell

Hypotonic

More solute inside cell (swell) water goes into the cell

Hypertonic

More solute outside the cell (shrink) water moves out of the cell

Endocytosis

Cell membrane engulfs large materials/cell turns into vesicle (active)

Exocytosis

Cell membrane expels materials, waste, ect. Turns from a vesicle (active)

Phagocytosis

Cell takes in solid materials

Pinocytosis

Cell takes in liquid materials

Types of materials that can cross the membrane easily

Small, non-polar oxygen and carbon dioxide

Types of materials that can’t cross the membrane easily

Larger, polar materials ions and glucose

Facilitated diffusion

Where the substances diffuse and have to go through transport proteins, driven by a difference in concentration

Why is water polar?

Water has oppositely charged ends (O- and H+)

Why do hydrogen bonds form?

Opposites attract (O- is attracted to H+)

Polar

Molecules with oppositely charged ends

Non-polar

Not charged at all

Solute

Substance being dissolved

Solvent

Substance doing the dissolving

Range of pH scale

0-14

Neutral on pH scale

Water (pH=7)

Type of ions associated with acids

H+

Types of ions associated with bases

OH-

What does neutral mean

Equal amounts of H+ and OH-

Buffer

When becoming too acidic, body releases weak base. When becoming too basic, body releases weak acid

Cohesion

Water attracting to itself (creating bodies of water)

Adhesion

Water attracting to other surfaces (water sticking to grass)

Capillary action

Water creeping up thin “tubes” (Cohesion and Adhesion) (Water getting from roots to leaves)

Surface tension

Creates stronger “force” on surface of water (Lets insects rest on water)

Ice is less dense that water

Ice molecules are placed further apart (Ice floats on oceans, creating insulation and protection for aquatic life)

Versatile solvent

Water easily dissolves ions/polar minerals (Lets our bodies dissolve vitamins and minerals

High specific heat

Water can absorb a lot of heat before temperature rises (Allows us to maintain homeostasis)

Turgor pressure

Water moves into the cell causing it to swell

Plasmolisis

Water exiting the cell causing it to shrivel

Sea water is _____ to the red blood cell

hypertonic water

Distilled water is _____ to the red blood cell

hypotonic water

Which molecule aids transmitting signals from outside to inside the cell?

carbohydrate

Which molecule keeps phospholipids from sticking to each other?`

cholestrerol

Which molecule aids in moving substances across the cell membrane, ex. facilitated transport

protein