The living cell

• a cell is the smallest unit of life that can carry out all the functions of life
• unicellular: a single-celled organism
• multicellular organism: organisms that have more than one cell type
• organisms can either be prokaryotic or eukaryotic
• eukaryotic cells: genetic material in a nuclear membrane
• eukaryotic cells have a nucleus
• eukaryotic cells have membrane bound organelles like mitochondria and chloroplasts
• plant and animals cells are eukaryotic
• prokaryotic cells do NOT have a nucleus
• prokaryotic cells lack membrane bound organelles and are not in a nuclear membrane
• bacteria are prokaryotic
• organelle: a structure found eukaryotic cells that performs a specific function
• protoplasm: the jelly-like substance that fills the cell and contains the cell's organelles
• the nucleus, cytoplasm and organelles make up the protoplasm
• the protoplasm is surrounded by the cell membrane
• animal cells have an irregular shape and are very small
• animal cells change their shape all the time
• plant cells are larger than animal cells and have a more regular shape
• plant cells also have chloroplasts, a vacuole and a cell wall
• cytoplasm is a thick liquid made up of 90% water and 10% proteins
• all chemical reactions take place in the cytoplasm
• the cytoplasm contains all the nutrients and materials for a cell to function
• the cell membrane is a semi-permeable membrane that controls what enters and leaves the cell
• glucose, oxygen and water enter the cell
• carbon dioxide and water exit the cell
• glycogen, starch and proteins are to big to pass through the pores
• the nucleus is an organelle that controls all cell functions
• the nucleus contains chromosomes
• the cytoplasm also has food granules floating around
• food granules are stores of food the cell keeps for future use
• food granules are NOT organelles
• food reserves:

  animal: Glycogen

  plant: Starch
• the mitochondria are the powerhouse of the cell
• mitochondria produce energy for the cell
• cells do NOT create energy, they produce it
• chloroplasts are bags full of chlorophyll
• chlorophyll is a green pigment that absorbs light energy
• the cell wall is an outer wall that is for protection
• the cell wall is made up of a carbohydrate called cellulose
• the cell wall is fully permeable to water