Characteristics

• Characteristics of living organisms

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

  Obtaining of food to provide energy and substances needed for growth, development and repair
• Nutrition in green plants

  1. Photosynthesis - energy from sunlight is absorbed and used to turn carbon dioxide and water into simple sugars

  2. Plants then convert these simple sugars into complex compounds, such as cellulose and proteins

  3. They need mineral ions from the soil to make proteins
• Nutrition in animals


  • Cannot make their own food like plants, so they have to eat plants or other animals to gain energy and nutrients
  • Process of taking in food is called ingestion
  • Food is digested, absorbed into the blood and then assimilated by cells for growth and repair
  • Food which is not digested and absorbed is egested in faeces
• Respiration


  • Chemical reactions that occur in cells to break down nutrients, such as glucose, to release energy
  • Oxygen is usually needed for respiration to happen
• Movement


  • Organisms move themselves or move parts of themselves into new areas or to change position
  • Plants move slowly when they grow - roots move down into the soil and leaves/stems move up towards the light
  • Most animals are able to move their whole bodies to obtain food or avoid predators
• Growth


  • Permanent increase in size of an organism, either an increase in cell number, cell size or both
  • Plants carry on growing throughout their lifetime, animals stop growing when they reach a certain size
• Excretion


  • Removal of waste substances in excess of requirements from the body
  • Plants excrete waste substances in their leaves, which fall off
  • Animals breathe out waste substances, which leave the body in the urine
• Sensitivity


  Ability of living organisms to detect changes in their internal and external environments and respond to them
• Reproduction


  • Organisms reproduce to make new individuals of the same species
  • Sexual reproduction involves two parents producing gametes which fuse to form a new individual
• Main groups of vertebrates

  • Amphibians
  • Fish
  • Birds
  • Reptiles
  • Mammals
• Amphibians


  • They have moist skin and can live both in water and on land
  • They undergo metamorphosis from larval to adult form
  • They breathe through gills as larvae and lungs as adults
• Fish


  • They live in water and have gills to breathe
  • They have scales and fins for swimming
  • They have a lateral line to detect prey
• Reptiles


  • They have dry, scaly skin
  • They are exothermic, meaning they rely on external sources to regulate their body temperature
  • They lay soft-shelled eggs on land
• Birds


  • They have feathers and wings to fly
  • They have a beak instead of teeth
  • They lay hard-shelled eggs
• Mammals


  • They have hair or fur
  • They are endothermic, meaning they can regulate their own body temperature
  • They give birth to live young and produce milk to feed them
• Sharks belong to the group of fish
• Amphibians have moist skin and most are able to live both in water and on land
• Reptiles have dry, scaly skin and lay soft-shelled eggs on land
• Birds have feathers and wings to fly, and lay hard-shelled eggs
• Mammals have hair or fur, are endothermic, and give birth to live young and produce milk to feed them
• Main groups of invertebrates(Athropods)

  • Insects
  • Crustaceans
  • Myriapods
  • Arachnids
• Arthropods


  • They have a hard exoskeleton
  • They have jointed legs
  • They have a segmented body
• Crustaceans


  • They have a hard exoskeleton
  • They have jointed legs
  • They live primarily in water
• Myriapods


  • They have many legs
  • They live primarily on land
• Arachnids


  • They have eight legs
  • They have two main body parts
  • They include spiders, scorpions, and ticks
• Ferns are a group of plants that have become well adapted for life on land
• Ferns have roots, stems, and leaves, and reproduce by making spores
• Flowering plants have true roots, stems, and leaves, and reproduce by making seeds
• Chloroplasts in the leaves of plants contain chlorophyll, which gives them their green colour
• Both ferns and flowering plants have vascular systems of xylem vessels and phloem tubes
• Dicotyledons and monocotyledons are two main groups of flowering plants, which can be distinguished by the number of cotyledons in their seeds