Cells

• Organism - A living thing that is made up of cells and has a functioning metabolism.
• Cell - A microscopic structure that is the building block of all organisms.
• Tissue - Group of similar cells working together to perform a particular function.
• Organ - An organized group of tissues performing a specific function.
• System - Organized groups of organs working together to carry out an overall function.
• Nucleus - Contains DNA which controls the activities of the cell.
• Cytoplasm - The jelly-like substance inside the cell membrane where most chemical reactions take place.
• Cell Membrane - Holds the cell together and controls the movement of substances into and out.
• Mitochondria - Site of aerobic respiration, producing ATP (energy).
• Cell Wall - Supports the cell and prevents it from bursting. Made of cellulose.
• Vacuole - Contains cell sap made from sugar, salts and water. Keeps the cell rigid.
• Chloroplasts - Carry out photosynthesis to make food (glucose) for the plant. Contains a green pigment called chlorophyll which absorbs light.
• Multicellular - Made of more than one cell.
• Unicellular - Made of only one cell.
• Specialised Cell - A cell that has a specific function and is adapted to carry out that function.
• Diffusion - The net movement of particles from an area of high concentration to low concentration.
• Respiration - The process in which energy is released from glucose for cells to use.
• Photosynthesis - The process which uses light energy to make food (glucose). Occurs in the chloroplasts of cells.
• Ribosome - Site of protein synthesis in the cell.
• Organisms can be formed from a single cell. Millions of cells can join to form a person.
• Animal cells have an irregular shape.
• Plant cells have a more regular structure compared to animal cells. This allows them to fit together like bricks.
• All the cells inside your body need glucose and oxygen for respiration. During respiration, energy is transferred and glucose and oxygen are transported around the body in the blood then they pass into the cells that need them.
• Some chemical reactions that occur inside cells, make waste products.
• Substances move into and out of cells by diffusion.
• Water fills up the vacuole and this pushes outwards onto the cell wall and makes the cell rigid; this helps the plant stand upright.
• If the plant doesn't have enough water, the vacuole shrinks and the cell becomes flaccid.
• M - Movement

  R - Respiration

  S - Sensitivity

  G - Growth

  R - Reproduction

  E - Excretion

  N - Nutrition
• Amoeba - A unicellular organism that has no fixed shape. Can be found in fresh water, salt water, wet soil and even inside animals.

  Pseudopod is a temporary projection of the cell used for movement and to engulf tiny particles of food to form a food vacuole.
• Bacteria - Very tiny unicellular organisms. It doesn't have a nucleus.

  Flagellum is a tail-like structure which allows bacteria to move.
• Yeast Cell - Unicellular fungi organism. They don't have chloroplasts but does have a cell wall. The cell wall gives the yeast cell a shape and provides strength to withstand external pressures.
• Unicellular organisms must reproduce. This is done through Binary Fission where they make copies of themselves and then divide into two.