week 2 - cells, tissues and skin

Selectively permeable

Allows some substances to pass while restricting others based on size, charge, or solubility

Water soluble

Substances that dissolve in water usually polar or charged

Active transport

Movement using ATP to move substances against their concentration gradient

Facilitated diffusion

Passive movement using membrane proteins down a concentration gradient

Hypertonic

Higher solute concentration outside the cell causing water to leave and the cell to shrink

Regeneration

Replacement of damaged tissue with the same type of cells restoring function

Lipid soluble

Substances that dissolve in lipids and easily cross the plasma membrane

Passive transport

Movement without ATP down a concentration gradient

Simple diffusion

Passive movement directly through the membrane from high to low concentration

Osmosis

Diffusion of water across a selectively permeable membrane

Hypotonic

Lower solute concentration outside the cell causing water to enter and the cell to swell

Fibrosis

Formation of collagen rich scar tissue replacing normal tissue

Membrane potential

Electrical charge difference across a membrane due to ion gradients

Plasma membrane

Phospholipid bilayer controlling movement of substances into and out of the cell

Phospholipids

Molecules with hydrophilic heads and hydrophobic tails forming the membrane bilayer

Fibroblasts

Cells that produce collagen and extracellular matrix for wound healing

Tonicity

Effect of a solution on cell volume based on solute concentration

Crenation

Shrinking of a cell in a hypertonic solution