organisms

• what is gas exchange

  The process of taking in oxygen and giving out carbon dioxide
• where does gas exchange occur

  in the respiratory system
• Why do the proportions of gases we inhale and exhale change?

  Using oxygen in respiration and producing carbon dioxide
• what happens when u inhale?

  muscles between the ribs contract

  ribs are pulled up and out

  diaphragm contracts and flattens

  volume of the chest increases

  pressure inside the chest decreases

  air rushes into the lungs
• what happens when u exhale?

  muscles between the ribs relax

  ribs are pulled in and down

  diaphragm relaxes and moves up

  volume in the chest decrease

  pressure inside the chest increases

  air is forced out of the lungs
• what are drugs


  drugs are chemicals that affect the way our body works
• what are medicinal drugs

  these type of drugs are used in medicine and benefit health but can harm if not taken in the correct way
• what are examples or medicinal drugs

  antibiotics paracetamol painkillers
• What are recreational drugs?


  Drugs taken for enjoyment
• why are recreational drugs bad

  they normally have no health benefits and can harm ur health
• what are examples of recreational drugs

  alcohol tobacco
• what is drug addiction


  when ur body gets so used to a drug it cannot cope without it
• what are withdrawl symptoms

  when someone who has an addiction stops taking drugs they will experience these and they can be very unpleasant and painful
• what does the salivary gland do

  produces digestive juice which is added into the mouth
• what does the liver do?

  produces bile which helps digestion
• what does the stomach do?

  Adds acids and is where digestion occurs
• What does the small intestine do?

  Digestion is completed here and absorption of soluble food occurs
• what does the pancreas do?

  this produces a digestive juice which is added into the small intestine
• what does the large intestine do?

  water is absorbed from the undigested food which then produces faeces
• what does a balanced diet involve?

  eating the right amount of nutrients for ur body to function
• what leads to a deficiency

  not eating enough of a nutrient means u have an unbalanced diet leading to a deficiency
• what is the role of carbohydrate?

  Main source of energy
• what is the role of lipids

  fats and oils provide energy
• what is the role of proteins

  growth and repair of cells and tissues
• what is the role of vitamins and minerals 


  essential in small amounts to keep u healthy
• What is the role of water

  Needed in all cells and body fluids
• what is the role of fibre

  provides bulk to food to keep it moving through the gut
• What is the order of the respiratory system

  air enters ur body

  air moves down the trachea

  air moves down a bronchus

  air moves through a bronchiole

  air moves into an alveolus-an air sac

  oxygen then diffuses into the blood
• what is represented in the bell jar model

  the jar represents ur chest the balloons represent ur lungs and the rubber sheet represents the diaphragm
• What factors can reduce/increase lung volume

  Smoking and asthma reduces lung volume while regular exercise increases lung volume
• what is a depressant 


  a chemical which slows down ur body’s reactions
• who is an alcoholic


  people addicted to alcohol
• why shouldn’t pregnant women drink alcohol

  the alcohol can diffuse into the baby’s bloodstream and damage the organs and nervous system. FAS affects the way a baby’s brain develops and can cause learning difficulties facial problems and weak immune systems
• what is cirrhosis of the liver

  when the liver works less efficiently and takes longer to break chemicals and alcohol down which can lead to death
• What are the harmful chemicals in tobacco

  Tar- a sticky black material which contains chemicals that cause cancer which also collects in the lungs and blocks airways

  Nicotine- a drug which id addictive and makes the heart best faster

  Carbon Monoxide- a poisonous gas which reduces the amount of oxygen the blood can carry
• what are enzymes


  enzymes are biological catalysts which speed up the digestion of nutrients
• Carbohydrases break carbohydrates down into simple sugars
• proteases break proteins down into amino acids
• lipase breaks lipids down into fatty acids and glycerol
• how do u test for starch

  u add iodine to the solution and if it turns dark blue-black it contains starch