BIO U.1

?
View mindmap
  • The Eight Characteristics of Life
    • Sensitivity
      • Ability to sense and respond to the external environment.
      • Special receptors detect stimuli {light, sound, temperature and gravity} allowing the organism to alter its behaviour or growth.
    • Respiration
      • Process of releasing energy from food, and is a series of chemical reactions inside all living cells.
      • The energy produced drives processes such as growth and movement, so is essential.
    • Growth
      • Organisms increase in size.
      • Plants grow  throughout their lifetime.
      • Animals grow from young into adults, increasing in size and developing
    • Movement
      • All organisms move in a controlled way.
      • Animals quickly and plants slowly. Not Venus fly trap.
    • Excretion
      • Removal of waste materials produced within cells (often during respiration) that would build up to toxic levels if not eliminated. (Urea, and carbon dioxide).
      • Simple single-celled organisms eliminate these materials via diffusion, more complex organisms have organ systems e.g. kidneys and bladder
    • Reproduction
      • Allows organisms to continue the species after death, and to colonise new habitats to extend their range.
      • Asexually when the offspring product of 1 parent so is genetically identical.
      • Sexually when the  offspring  product of two parents. Gametes produced by both come together resulting in fertilisation –often by very elaborate means.
    • Environment
      • Control of the internal environment.
      • Maintaining a constant internal temperature, maintaining a suitable oxygen concentration, water levels, even pH, all allow cellular processes to proceed at their optimum rates.
    • Nutrition
      • Organisms need a source of food which can be respired to produce energy.
      • Plants combine carbon dioxide with water to produce simple sugars and oxygen as a by-product Photosynthesis. Autotrophs.
      • Other organisms eat other plants and animals (heterotrophs), some by feeding on dead plants and animals (saprobionts) and some bacteria can oxidise inorganic compounds.

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Variety of life and classification resources »