Health and pathogens Flashcards
What is a “healthy diet”
A healthy diet is one which contains the right balance of different foods and the right amount of energy
What are carbohydrates, fats and proteins used for by the body?
What are mineral ions and vitamins needed for in the body?
Releasing energy and building cells
Mineral ions and vitamins are needed to keep the body healthy.
What happens if a person’s diet is not balanced?
They can become malnourished, which may lead to being over- or underweight, and could also lead to deficiency diseases or conditions such as Type 2 diabetes
What happens when the energy content of food taken in is less than the amount of energy expended by the body?
How is this level of energy expended increased?
The person loses mass
Increased Exercise
Define metabolic rate.
What factors affect an individual’s metabolic rate?
The rate at which all chemical reactions in the cells of the body are carried out.
The amount of activity one does, one’s proportion of muscle to fat, and inherited factors
Give two examples of when inherited factors affect our health.
Metabolic rate
Cholesterol level
What condition can long-term obesity lead to and how can these problems be reduced?
If someone is unhealthy because they have too little food what may they suffer from and why?
Long-term obesity can lead to Type 2 diabetes (high blood sugar), these problems can be reduced by eating less carbohydrate and increasing the amount of exercise.
They may find it difficult to walk about and may suffer from deficiency diseases due to a lack of vitamins and mineral.
Define a pathogen
A microorganism that causes infectious disease
Give three ways in which white blood cells help to defend against pathogens
Ingesting pathogens
Producing antibodies, which destroy specific bacteria or viruses
Producing antitoxins, which counteract the toxins released by the pathogens
How does immunity to a pathogen come about in the body?
The immune system produces specific antibodies to kill a specific pathogen, then stores them, so that it can react quickly and destroy that pathogen in the future. Sometimes, dead or inactive pathogens can trigger white blood cells to produce antibodies (such as in vaccination).
Summarise Semmelweis’ findings
He insisted that doctors washed their hands before contacting and examining patients, which greatly reduced the number of deaths from infectious diseases in his hospital. He thus discovered that washing hands prevents the spread of these diseases
What are antibiotics used for, and name the first one to be discovered (Alexander Fleming)?
Why are viruses difficult to kill?
Antibiotics are medicines that help cure bacterial disease by killing certain bacteria within the body. They can NOT kill viral pathogens.
Penicillin
Viruses are difficult to kill because they reproduce inside body cells, so any treatment could also damage the body cell.
How do we avoid antibiotic resistant strains of bacteria arising?
Specific bacteria should be treated with specific antibiotics to avoid bacteria becoming resistant to antibiotics
Use minimal quantities, only with a serious bacterial infection (not for things like a mild throat infection)
Develop new antibiotics continually
How do pathogens (say, MRSA) produce strains that are resistant to an antibiotic (say, methicillin)?
Why is this dangerous?
Mutations produce new strains, some of which happen to be resistant to the antibiotic
Antibiotics kill the original, non-resistant pathogens - resistant ones survive and reproduce, passing on their genetic immunity
Soon a whole population of a resistent strain devlops, these are often dangerous because there is no effective treatment
What are painkillers used for?
Why are they no good by themselves?
They relieve symptoms, making the person feel well.
They do not kill the pathogens that are causing the problems.
