CELL PROCESSES

Diffusion

movement of particles from high to low concentration (e.g. oxygen diffuses from lungs to blood)

Osmosis

movement of molecules through a semi-permeable membrane from high to low concentration (e.g. water entering plant root cells)

Active transport

movement of substances against the concentration gradient (e.g. photosynthesis sugars make their way from leaf to fruit)

Cellular respiration

release energy for cell activities, happens in mitochondria

Aerobic respiration equation

glucose + oxygen—>carbon dioxide + water + energy

Anaerobic respiration equation

glucose—>lactic acid + less energy

Photosynthesis

requires light energy, water, carbon dioxide; produces glucose and oxygen

Photosynthesis equation

Carbon dioxide + water + light—>glucose + oxygen

Exocytosis

Cell pushes out substances

Endocytosis

cell takes in large particles by engulfing them

When are endocytosis and exocytosis used?

when substances are too large for diffusion or active transport

Homeostasis

cells maintain stable internal conditions; maintains ph, ion balance, water levels

Processes involved in homeostasis

osmoregulation and temperature control

Gas exchange

exchange of oxygen and carbon dioxide, happens through diffusion

Where does gas exchange in animals take place

takes place in lungs(alveoli) and bloodstream

Where does gas exchange in plants happen

takes place in stomata