Keeping Healthy

Balanced Diet
1. Consists of carbohydrates (energy, sugar and starch), proteins (amino acids, growth and repair, make up enzymes which denature at 40C), Fibre (aids digestion), water (all chemical reactions take part in it.
  1. Fats (fatty acids and glycerol, storage of energy, insulators, steroid production), vitamins (keeps us healthy, Vit C - immune system, Vit D - bones), minerals (e.g. irons - carries oxygen to red blood cells, calcium + magnesium, salt - muscle contractions)
2. Weight Problems
  1. If you take in more energy than you use, you will store excess fat.
    1. Obesity can cause arthritis, type 2 diabetes, high blood pressure and heart disease.
  2. Lose weight by reducing energy intake and doing more exercise.
  3. People who do not eat enough can suffer from deficiency diseases (not enough vitamins or minerals)
3. Metabolic Rate
  1. The rate at which someone digests food, the rate of chemical reactions differ between different people.
    1. Affected by proportion of muscle to fat and how much exercise one does. THe metabolic rate can also be inherited.
4. Cholesterol
  1. For making vital hormones and for the cell membranes. Risk of heart disease if good and bad cholesterol levels are unbalanced.
    1. Made by liver, eating high fatty foods affects levels, can be inherited, doing regular exercise lowers it.
Pathogens & Disease
1. Infectious diseases: when microorganisms enter and attack the body.
  1. Symptoms: high temp, headaches, rashes.
  2. Can become infected by: droplet infection - influenza, direct contact - conjunctivitis, contaminated food and drink - cholera, through a break in the skin - hepatitis.
2. Bacteria & Viruses
  1. Viruses(e.g. rabies, hepatitis) are smaller and regularly shaped, some bacterium are good for the body. Viruses enter the cell though bacteria (e.g. leprosy, cholera) attack from the outside Viruses do not produce toxins, but they take over the body. Bacterium split in two to reproduce (binary fission).
3. Pathogens make you feel ill as they can produce toxins and reproduce rapidly. They damage your tissues.
4. 1st Line Defence Mechanisms: Skin - sebum (water proof oil), forms scabs, dead skin on outer layer
  1. Ears - wax: antiseptic
  2. Eyes - tears: clear dirt, antiseptic: alkali
  3. Lungs - mucus: traps pathogens
  4. Mouth - saliva: alkali, stomach acids
  5. Nostrils - cilia hairs, mucus
5. 2nd Line Defence: the white blood cell
  1. Ingesting - eats pathogen
  2. Produces antibodies that connect to and defeat the pathogen, a different one needs to be made each time, though they can be created easily the next time similar pathogen enters the body.
    1. Antitoxin - creates antitoxins that counteract the toxin from the pathogen.
Antibiotics
1. Painkillers do not treat illness, they cure symptoms. e.g. paracetamol, aspirin.
  1. Antibiotics kills the bacteria
2. Only treat Bacteria as viruses reproduce inside the cell. Cannot develop medicine that is not dangerous when killing viruses
3. Penicillin - Discovered by Alexander Fleming
  1. In 1928: growing bacteria on agar plates
    1. The lids were off, clear rings of something had grown around and killed the bacteria.
      1. He gave up on penicillin as he couldn't make it survive by 1934
        Ernst Chain and Howard Florey used it on people ten years later. They kept working on it and brought it to an industrial scale.
        It was used to supply the demands of WW1
        Successful with Blood infections and Septic Wounds
Growing Bacteria
1. One needs a culture medium (usually agar jelly) to provide carbohydrates, minerals and rich nutrients as an energy source.
  1. Need warmth and oxygen to grow
2. We culture (grow) micro-organisms to help us learn about them, medical and scientific research.
3. Petri-dish, inoculating loop (thing you use to transfer bacteria) and agar must be sterilised.
  1. Avoid contamination = accurate results and no dangers.
    1. A mutation of the bacteria, in hot temperatures they reproduce very quickly. Carbon dioxide builds up as a waste product.
  2. Dip loop into suspension of thing you want to grow.
    1. Seal dish to prevent growth of unwanted micro-organsims or escape of culture. Oxygen still needs to get to the culture. The petri dish it turned upside down so condensation that forms will fall onto the culture.
      1. Incubate at 25C (in schools) to allow culture to grow. In labs it is a much higher temperature as it speeds growth.
Changing Pathogens
1. Bacteria can mutate and become resistant to anit-biotics which can lead to a new strain of disease.
  1. 95% bacteria is killed by Antibiotic 1. 5% left reproduce, 95% are killed by antibiotic 2. Process continues: the third colony of bacteria is resistant to Antibiotic 1&2
2. Caused by over use of antibiotics when they are not needed. Doctors prescribe when it is viral, people do not finish course of meds.
  1. MRSA: Antibiotic resistant bacteria spread from patient to patient around the hospitals
    1. Mutations cause new diseases which spread easily as people are not immune to them and there is no effective treatment yet.
Immunity
1. Dead or inactive pathogen injected
  1. This causes white blood cell to create antigen or antibody to defeat pathogen
    1. The pathogen cannot harm you
      1. The next time the pathogen (virus or bacteria) enters body the white blood cells will be prepared as they have created antibodies before of the same type to match the pathogen.
2. MMR vaccine: measles, mumps and rubella. Small pox has been wiped out
3. Then Vaccine Debate - Small risk of side effects, can have a biased view by doctor (vaccination targets set by government) though vaccinations protect you from infectious diseases.

Nächster

Keeping Healthy

Beschreibung

Zusammenfassung der Ressource

ähnlicher Inhalt

	Erstellt von Grace Pulling vor mehr als 11 Jahre