Diffusion & Living Organisms

Heterotrophs

Organisms that gain nutrients by eating other organisms because they cannot make their own food

Autotrophs

Organisms that make their own food, usually by photosynthesis

Saprotrophs

Organisms (like fungi) feed on dead or decaying material by secreting enzymes and absorbing the nutrients.

Eukaryote

An organism with cells that have a nucleus and membrane-bound organelles ( plants, animals, fungi).

Prokaryote

An organism with cells that have no nucleus and no membrane-bound organelles (bacteria).

Diffusion

Diffusion is the net movement of particles from a high concentration to a low concentration. This difference is known as the concentration gradient.

Osmosis

Osmosis is a special case of diffusing involving water. It is the net movement of water molecules from a region of high concentration to a region of low concentration through a selectively permeable membrane.

Active Transport

Active transport is the movement of a substance from an area of low concentration to an area of high concentration. This process requires energy from aerobic respiration.  

Animals

• Eukaryote

• Heterotrophs

• No cell wall

• Glycogen

• Multicellular

• Human, Elephants

Plant

• Eukaryote

• Autotrophs

• Cellulose

• Starch or Sucrose

• Multicellular

• Rose, Corn

Protist

• Eukaryote

• Autotrophs

• Some have a cell wall and some don’t

• Glycogen

• Single-celled

• Amoeba, Chlorella

Fungi

• Eukaryote

• Saprotrophs

• Chitin

• Glycogen

• Both multicellular and single-celled

• Mushroom, Yeast

Bacteria

• Procaryote

• Autotrophs

• No cell wall

• Glycogen

• Single-celled

• Pneumococcus, Lactobacillus

Viruses

• Cellulose

• HIV, Tobacco Mosaic Virus