ap bio 5.1-5.3/labs

Diffusion

Movement of particles from high concentration → low concentration.

Osmosis

Movement of water across a selectively permeable membrane from high water potential → low water potential.

Solute Potential

A solution will have a lower and hence more negative water potential than that of pure water. Furthermore, the more solute molecules present, the more negative the solute potential is.

Pressure Potential

: Physical pressure on either side of the membrane.

Isotonic:

Equal water potential on either side of the membrane. Random diffusion across the membrane still occurs, but it is equal and opposite.

Hypotonic:

A solution with a higher concentration of free water molecules. Solutes low.

Hypertonic

: A solution with less free water molecules in solution. Solutes high.

Turgor

A measure of plant cells filling up with water, exerting pressure on the cell walls. Keeps plants upright.

Flaccid

: A plant cell that has lost turgor pressure and is wilting.

Plasmolysis

: the pulling away of a plant’s cell membrane from the cell wall as turgor pressure is lost.

Autocrine

A cell releases a signal that acts on the same cell.

Juxtacrine

A signal acts on a neighboring cell through direct cell-to-cell contact.

Paracrine

A cell releases a signal that acts on nearby cells.

Endocrine

A cell releases hormones into the bloodstream to act on distant cells.

NaCl (salt) ionization constant

2

Glucose ionization constant

1

Low molarity

more positive change, mass goes UP

High molarity

more negative change, mass goes DOWN

phenolphthalein + HCL

Clear, acid

phenolphthalein + NaOH

pink, base

Guard cells

specialized cells surrounding the pores in leaves called stomata

What would happen if you were given pure water in an IV?

Water would move into cells, burst