Unit 1: Chapter 1 - Keeping Healthy Flashcards
What is the consequence of a lack of vitamins and minerals?
Why might there be deficiency in some parts of the world?
You will be malnourished.
Certain foods can be genetically modified to contain vitamins so there is small chance of being malnourished in Britain.
On the other hand, this may be that there is a lack of food, civil wars, droughts and pests which destroy crops.
How much energy do you need?
What factors affect how much energy you need?
Depends on certain factors such as age, gender, and even how much exercise you do.
Generally women need less energy than men, however when pregnant they need more energy.
What is the metabolic rate?
How does the metabolic rate vary between people?
The rate of chemical reactions with cells.
This depends on genetic factors, but also depends on how much activity you do.
A higher muscle to fat ratio will increase the metabolic rate.
What is obesity?
A form of malnourishment.
Consuming more food than you need will cause your body to store fat and overtime you will become overweight or obese.
How to lose weight?
To lose weight effectively you need to eat less calories than you use but also increase the amount of time you do exercise.
What are inherited factors?
Inherited factors are controlled by your genes. They affect your appearance but also your health.
Some examples are metabolic rate, cholesterol levels Etc.
What are pathogens and disease?
What are bacteria and viruses?
Who was Ignaz Semmelweis and what was he known for?
Pathogens are harmful micro-organisms. These create infectious diseases.
Some examples are bacteria and viruses.
Bacteria are smaller than plant cells and are not always harmful.
Ignaz Semmelweis introduced antiseptic to doctors when child bed fever death rates were very high in the mid-1850s.
Viruses are always harmful and dependant on a host. These are smaller than bacteria.
How do pathogens infect?
Droplet infection - sneezing + coughing + talk which can be contracted through the breathing system. E.g. Flu.
Direct contact - contact of skin. E.g. Genital herpes + impetigo.
Contaminated food/drink- eating raw/ undercooked food or drinking water containing sewage. For e.g. Salmonella.
Through break in skin- needle punctures + scratches. For e.g. HIV.
What are the main defence mechanisms?
Excluding immune system
Skin - Barrier.
Platelet cells - clots blood to form scab over cuts.
Goblet cells - produces mucus and traps. Epithelial cells sweep mucus from trachea to mouth to swallow to stomach.
Stomach acid - high pH acid destroys pathogens.
Tears - enzymes in tears to break down pathogen.
How does the immune system defend the body?
Ingestion micro-organisms - ingest and destroys pathogens
Producing antibodies
- White blood cells produce antibodies.
- Unique antibody for unique antigen on pathogen
- Immune system memorises this antigen and can rapidly produce this particular antibody.
Producing anti-toxins - White blood cells produce anti-toxins to counteract toxins.
Which drugs do you need to treat viruses and bacteria?
Antibiotics can only kill bacteria.
Virus live within our cells so you would have to destroy the cell to destroy the virus.
Painkillers reduce symptoms but doesn’t kill the disease.
Alexander Fleming (discovery in 1929) found ‘penicillin’.
How do you culture bacteria?
What conditions do you require?
What is the maximum temperature to culture at school?
How do you innoculate and culture a suspension? (Method)
Culture (grow) means you need to provide correct conditions of the micro-organisms. These include:
- Carbs as an energy source
- Various minerals
- Warmth
- Oxygen
Schools can only culture at a maximum temp of 25C.
How do you do it?
- Sterilise inoculating loop (Bunsen burner)
- Cool but do not blow
- Dip in suspension and scrap against agar jelly in the petrol dish
- Replace life as quickly as possible to avoid contamination
- Do not seal completely. No oxygen will force bacteria to anaerobically respire which may be harmful.
What happens if bacteria mutate?
How can we prevent creating anti-biotic resistant bacteria?
How can we prevent the spread of disease?
A change in genetic material will produce a new strain of bacteria.
To prevent creating bacteria resistant to antibiotics, we must:
- Use only on serious diseases
- Complete course of antibiotics
- Correct antibiotic must be used
To prevent spread of resistant bacteria:
- Hygiene must be at its optimum
- Hospitals kept clean
What are pandemics and epidemics?
Pandemics are diseases spread across the world.
Epidemics are disease spread across the country.
What is immunity?
How does immunisation work?
To be immune, you must have a vaccination or immunisation.
Immunisation works by injecting DEAD or MODIFIED pathogens in the body.
The person will not gain any symptoms as the pathogen is not active. The antigens on the surface of the pathogen stimulate the immune system.
There is a slow production at first of antibodies to destroy these pathogens.
The body is immune to that infection in the future as it remembers the antigens and can produce antibodies RAPIDLY.
An example of a vaccination is the MMR for Mumps, measles and Rubella.
