cells & organelles

• MRS C GREN


  Characteristics shared by all living things: Movement, Respiration, Sensitivity, Circulation, Growth, Reproduction, Excretion, Nutrition
• Biology


  The study of living things
• Living object


  An object that carries out life functions
• Non-living object


  An object that has not been alive
• Dead object


  An object that was once alive
• Cell


  A small, membrane-bound compartment that contains all the chemicals and molecules that help support an organism's life
• Life functions


  • Movement
  • Respiration
  • Sensitivity
  • Circulation
  • Growth
  • Reproduction
  • Excretion
  • Nutrition
• Movement


  The ability to move through space
• Respiration


  The ability to obtain energy through biochemical reactions
• Sensitivity


  The ability to respond to stimuli
• Circulation


  The ability to move nutrients, oxygen, heat and water around the body
• Growth


  The ability to increase in size
• Reproduction


  The ability to create more living things
• Excretion


  The ability to dispose of waste chemicals
• Nutrition


  The ability to extract useful chemicals from the environment
• All living organisms are composed of cells
• Prokaryotic cells


  Cells without a membrane-bound nucleus
• Eukaryotic cells


  Cells with a membrane-bound nucleus
• Humans have 100 trillion cells
• Types of organisms


  • Unicellular
  • Multicellular
• Unicellular organism


  A fully functioning (MRS C GREN) independent cell unit that can be grouped into colonies but are still able to separate and survive
• Multicellular organism


  Cells within an organism are specialised to perform a life function (or part of one), single cells cannot live independently, all cells co-ordinate into one organism to collectively perform all the functions of life
• Types of cells


  • Animal
  • Plant
  • Bacteria
  • Virus
• Animal cell


  Enclosed by a plasma membrane and containing a membrane-bound nucleus and organelles, small vacuoles, no chloroplasts, no cell wall
• Plant cell


  Similar to the animal cell, but does not have centrioles, lysosomes, cilia, or flagella, has a rigid cell wall, central vacuole, and chloroplasts
• Bacterial cell


  Does not have nucleus or organelles (except ribosomes)
• Virus


  Not considered living or consisting of cells but contains genetic material (RNA/DNA) similar to all other living things
• Organelle


  Specialized compartmented structures that perform particular functions in a cell
• Plant cell organelles


  • Cell membrane
  • Cytoplasm
  • Nucleus
  • Cell wall
  • Vacuole
  • Chloroplast
• Animal cell organelles


  • Cell membrane
  • Cytoplasm
  • Nucleus
  • Mitochondria
  • Endoplasmic reticulum
• Cell wall


  Gives the cell rigidity and a more angular appearance
• Chloroplast


  The site of photosynthesis, gives the cell its characteristic green colour (chlorophyll)
• Vacuole


  Assists with storage and structure
• Photosynthesis


  Chemical reaction that uses light energy to convert CO2 and Water to glucose (Plant food) and oxygen
• Chlorophyll


  Green pigment in chloroplasts that is the primary pigment for photosynthesis, two types: chlorophyll a (blue/green) and chlorophyll b (dull green-yellow)
• Cell membrane


  Surrounds cell and controls passage of nutrients and chemicals, flexible and allows cell to change shape
• Mitochondria


  Organelle where respiration occurs, sugar is broken down and energy is released
• Plasma membrane


  Membrane layer called the Phospholipid Bilayer, with round hydrophilic "heads" and long hydrophobic "tails" in a fluid mosaic model, semi-permeable
• Respiration


  Process where cells take in oxygen and use it to breakdown glucose into a usage form (ATP)
• Nucleus


  Stores the cell's DNA and coordinates the cell's activities, including growth and reproduction (cell division)