Keep healthy, defending against infections Flashcards
What two things do you need for the body to be healthy?
Balanced diet
Regular exercise
What can be used to prevent infection?
Vaccination
What is a ‘healthy diet’?
The right balance of food and the right amount of energy
What do, carbohydrates, fats and proteins do?
Release energy
Build cells
What helps build cells and release energy
Carbohydrates
Fats
Proteins
Mineral ions and vitamins are needed in what amounts and what for?
Small amounts for healthy functioning
What are needed for healthy functioning in small amounts?
Mineral ions
Vitamins
If a person doesn’t have a balanced diet they are …
Malnourished
What can being malnourished lead to?
A person being over or underweight
What else can an unbalanced diet lead to?
Deficiency diseases
Type 2 diabetes
Why could person lose mass?
If the amount of energy taken in is less than the amount of energy expanded (given) out
Energy ……. the energy expanded by the body
Increases
What is a metabolic rate?
The rate at which all the chemical reactions take place
The rate at which all reactions take place is called the ………
Metabolic rate
What does the metabolic rate vary with?
The amount of activity done
The proportion of muscle to fat in the body
What also affect health such as cholesterol levels?
Inherited factors
What do inherited factors do?
Affect health such as cholesterol levels
What are pathogens
Microorganisms that cause infectious diseases
What are microorganisms that cause infectious diseases?
Pathogens
Bacteria and viruses may ……. rapidly and produce …… which could make us ….. …
Reproduce
Poisons
Feel ill
What caused us to feel ill by producing poisons and reproducing rapidly?
Bacteria
Viruses
What do viruses do to cells that they reproduce in?
Damage them
What damages cells that they reproduce in?
Viruses
What do white blood cells do? (3 things)
Engulf and digest (ingest) pathogens
Produce antibodies
Products antitoxins
What do antibodies do?
Destroy certain bacteria and viruses
What do antitoxins do?
Counteract toxins released by pathogens
What does the immune system do?
Produce specific antibodies to kill a particular pathogen
How does the body get immunity of a pathogen?
By the immune system producing specific antibodies to kill a particular pathogen
What can stimulate antibody productions?
Dead or inactivated pathogens
What happens if a large potion of the population is immune to a pathogen?
The spread of the pathogen is reduced
Who recognised the importance of washing hands?
Semmelweiss
What happened when doctors started washing hands before examining patients?
The number of deaths by infectious diseases is reduced
What do some medicines (including painkillers) do and not do?
Only reduce symptoms but not kill the pathogen
What do antibiotics do?
Help cure bacterial diseases by killing infectious bacteria inside the body
What can’t antibiotics do and why?
They can’t kill viral pathogens because they live and reproduce inside cells
What happens with overuse and inappropriate use of antibiotics?
They increase the rate of development of antibiotic resistant strains of bacteria
What produces new strains of pathogens?
Mutations
What do new strains of pathogens mean for antibiotics and vaccinations?
They may no longer be effective against new strains
What happens to new strains and why?
They spread rapidly as people are not immune to them and there is no effective treatment
Why have many strains of bacteria developed resistance to antibiotics?
Natural selection
How to prevent further resistance?
Avoid overuse of antibiotics
What can antibiotics kill?
Individual pathogens of the non resistant strain
What happens to individual resistant pathogens?
They survive and reproduce so the populations of the resistant strain increases
Why are antibiotics no longer used to treat mild infections?
So the rate of development of resistant strains is slowed down
What does the development of new resistant strains of bacteria mean?
The development of new antibiotics is necessary
How can people be immunised?
By introducing SMALL quantities of dead or inactive forms of the pathogen (vaccination)
What do vaccines do?
Stimulate white blood cells to produce antibodies
What do the antibodies produced by white blood cells do?
Make the person immune to future infections by microorganisms
The body can respond by rapidly making the correct antibody…
In the same way as if the body had already had the pathogen
What is an MMR vaccine used for?
To protect children against measles, mumps and rubella
What must be done the Petri dishes and culture media before investigations take place?
They must be sterilised to kill any unwanted microorganisms
What must be done to inoculating loops before investigations take place?
Must be sterilised by passing them through a flame
What must happen to the lid of the Petri dish before investigations take place?
It should be secured with tape to prevent microorganisms from the air contaminating the culture
What is the temperature cultures should be kept at in schools and why?
Maximum 25 degrees to reduce the likelihood of growth of pathogens which can be harmful to humans
What happens if the temperature of cultures is kept at higher than 25 degrees?
Cultures can produce more rapid growth
