The Nature and Variety of Organisms

• What are the 8 characteristics all living organisms have?

  1. MRS GREN: Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, Nutrition
• Name organelles that both plant and animal cells have (describe their functions.)

  Nucleus, mitochondria, cell membrane
• What is a tissue?

  A group of cells that perform a specific function.
• What is an organ?

  A group of tissues that work together to perform a specific function in the body.
• What is an organ system?


  An organ system is a group of organs that work together to perform a specific function in the body.
• What is cell differentiation?

  Cell differentiation is the process by which cells become specialized in structure and function.
• Give two ways embryonic stem cells could be used to cure a disease

  Embryonic stem cells can replace faulty cells
• What are plant cell walls made of

  Cellulose
• How do most animals store carbs?

  Glycogen
• Define saprotrophic nutrition


  1. secrete digestive enzymes into food outside their body 2. break down food 3. absorb all nutrients
• What are Saprotrophs?


  Organisms that feed on the dead and decaying matter
• Give two examples of protoctists

  Chloroplasts, Amoeba
• Give three features of viruses

  They are particles, Are made up of genetic material (DNA or RNA), can only reproduce inside of living cells. (parasite)
• Give two examples of a Pathogen

  Viruses and fungi
• What is the name given to a biological catlyst?


  Enzyme
• What is a catalyst? 


  a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change.
• What does it mean when an enzyme has been denatured?

  Denaturation of enzymes causes bonds to be broken, structure to be disrupted and it stops functioning
• What is diffusion?


  Diffusion is the movement of particles from an area of high concentration to an area of low concentration.
• What is osmosis?


  Osmosis is the movement of water molecules from an area of lower solute concentration to an area of higher solute concentration across a semi-permeable membrane.
• What is Active Transport vs Passive Transport

  Active transport requires energy for the movement of molecules whereas passive transport does not require energy for the movement of molecules
• How does the surface area to volume ratio affect the movement of substances in and out of cells?

  The larger the surface area to volume ratio, the quicker the rate of diffusion takes place