Biological Terms

science

Biological words that are often confused

Excretion     removal of waste products produced by the body cells

e.g. urine, expired air.

Egestion

(defaecation)     removal of solid wastes from the gut i.e. faeces;

undigested food that has never entered the blood or body cells.

Ingestion (eating)     taking in food through the mouth.

Digestion     breakdown of food using enzymes, into simpler soluble products e.g. starch, sugars (though may be helped by acid conditions in the stomach, or bile from the liver)

Indigestion (acid)     food not properly digested in stomach causing stomach ache. May be due to too much acid being produced (neutralised by weak alkali)

Breathing     taking in (inhaling) and getting rid (exhaling) of air using the lungs.

Respiration     breakdown of food in the cells to produce energy

Aerobic respiration     breakdown of food using oxygen

Sugar + Oxygen ––> Water + Carbon dioxide + lots of ENERGY

Anaerobic respiration     breakdown of food without oxygen e.g. fermentation

      Sugar no oxygen ––>Alcohol + Carbon dioxide + little ENERGY

Photosynthesis     process by which food is made by plants from simple chemical substances

      Water + Carbon dioxide

    light energy

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chlorophyll     Sugar + Oxygen

Artery     blood vessel that carries blood away from heart (most carry oxygenated blood, except one going to lungs)

Vein     blood vessel that carries blood towards heart (most carry deoxygenated blood, except one coming from lungs)

Capillary     very narrow blood vessels that connect arteries to veins (allow food and oxygen out to the cells in exchange for wastes e.g. carbon dioxide and urea)

Red blood cells     carry oxygen by combining with the red pigment haemoglobin

White blood cells     fight disease by either surrounding germs and digesting them or by producing antibodies

Bacteria     very small, microscopic organism or microbes some of which cause disease e.g. Cholera, Typhoid, Tuberculosis(T.B.), Pneumonia,

Bubonic plague, Salmonella (food poisoning), others are useful

e.g. Bacteria of decay, Yoghurt bacteria, Cheese bacteria

Viruses     even smaller microbes, all of which cause disease e.g. Cold, Influenza('flu), H.I.V.( A.I.D.S.), Polio

Further Biology Reading

Click title to download
(all Word Documents)

  • Plant Reproduction
  • Carbon Cycle
  • Revision Sheet – Classification of major groups of organisms
  • Living Things in the Environment
  • Plant Nutrition
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