Science Revision Organisms Flashcards
what is gas exchange?
is the process of taking in oxygen and giving out carbon dioxide.
where does gas exchange occur?
in the respiratory system.
what happens when you breathe in?
your muscles between the rubs contract
your ribs are pulled in and out
volume of your chest increases
air rushes to your lungs.
what happens when you breathe out?
your muscles between your ribs relax
your diaphragm relaxes and move up.
what are drugs?
they are chemicals that affect the way that out body works.
what are recreational drugs?
they are taken by people for enjoyment. they can be harmful to health. eg. alcohol and tobacco.
what is drug addiction?
is when your body gets so used to a drug it feels as though it can not live without it.
what does the salivary gland do in the digestive system?
produces a digestive juice which is added into the mouth.
what does the large intestine do in the digestive system?
water is absorbed from the indigestive food which then produces faeces.
what are enzymes?
they are biological catalysts, they speed up the digestion of nutrients.
what do proteases break?
protein.
what do lipase break?
lipids.
what is the role of lipids?
fats and oils providing energy.
what is water needed in?
needed in all cells and body fluids.
what is the role of fibre?
provides bulk food to keep it moving through the gut.
