Bios in 2 days lord save me

• Movement


  Action done by an organism or part of an organism causing a change of position or place
• Respiration


  Chemical reactions in cells that break down nutrient molecules and release energy for metabolism
• Characteristics of living organisms (MrsGREN)

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


  Ability to detect or respond to changes in the external environment
• Growth


  Permanent increase in size and dry mass
• Reproduction


  Process that makes more of the same kind of organism
• Excretion


  Removal of waste products of metabolism and substances in excess of requirements
• Nutrition


  Taking in of materials for energy, growth and development
• Organisms can be classified into groups by the features they share
• Species


  A group of organisms that can reproduce to produce fertile offspring
• Binomial system of naming


  Internationally agreed system where the scientific name of an organism is made up of two parts showing the genus and species
• Constructing and using dichotomous keys


  Based on identifiable features
• Classification systems


  Aim to reflect evolutionary relationships
• DNA sequence


  Used as a means of classification
• Evolutionary relationships


  Groups of organisms which share a more recent ancestor are more closely related and have more similar DNA base sequences
• Main groups of vertebrates

  • Mammals
  • Birds
  • Reptiles
  • Amphibians
  • Fish
• Five kingdoms of organisms

  • Animal
  • Plant
  • Fungus
  • Prokaryote
  • Protist
• Plant groups


  • Ferns
  • Flowering plants: dicots and monocots
• Viruses


  Made up of a protein coat and genetic material
• Cell structures


  • Cell wall
  • Cell membrane
  • Nucleus
  • Cytoplasm
  • Chloroplast
  • Ribosomes
  • Mitochondria
  • Vacuole
• Bacterial cell structures


  • Cell wall
  • Cell membrane
  • Cytoplasm
  • Ribosomes
  • Circular DNA
  • Plasmids
• Cell

  Smallest unit of living organisms
• Tissue


  Group of cells with similar structure and function
• Organ


  Structure made up of a group of tissues
• Organ system


  Group of organs working together to perform a specific function
• Organism


  Individual living thing
• Magnification

  Calculated as image size / actual size
• 1 mm = 1000 micrometres
• Diffusion

  Net movement of particles from a region of higher concentration to a region of lower concentration down a concentration gradient, driven by the random movement of molecules and ions
• Substances move into and out of cells by diffusion through the cell membrane
• Factors affecting diffusion


  • Surface area
  • Temperature
  • Concentration gradient
  • Distance
• Osmosis


  The net movement of water molecules from a region of higher water potential to a region of lower water potential through a partially permeable membrane
• Turgid


  Plant cell with high water pressure pushing outwards on the cell wall
• Flaccid


  Plant cell with low water pressure, cell walls are not fully expanded
• Plasmolysis


  Shrinkage of the cell contents away from the cell wall due to loss of water
• Water potential and osmosis are important for the uptake and loss of water by organisms
• Turgid


  A plant that is very hard because there's a lot of water inside
• Flaccid


  A plant that is going or bending downwards
• Plasmolysis


  The movement of water
• You have to know the terms turgid, flaccid and plasmolysis and understand what they mean