Chapter 1 Keeping Healthy Flashcards
What is metabolic rate
The rate at which chemical reactions in the cells of the body are carried out
Why do you need cholesterol in your body
To make the membranes of your body cells and maintain normal hormone production e.g. your sex hormones
How could you change your cholesterol levels
By exercising and reducing the amount of fat in your diet
How do pathogens make you feel ill
Pathogens reproduce rapidly inside your body
they damage your cells
they produce toxins that make you feel ill
How are viruses different to bacteria
Viruses are smaller than bacteria
What are the three main ways your body prevent pathogens from getting in
Skin acts as a barrier; breathing organs produce mucus to trap pathogens or acid in the stomach kills pathogens; blood uses platelets to produce clots to seal all wounds
What are the 7 components of staying healthy ?
Carbohydrates Fats Protein Vitamins Minerals Fibre Water
How do white cells protect you from diseases
They ingest micro organisms; they produce antibodies; and they produce antitoxins which counteract the toxins released by pathogens
How do antibiotics work
They damage bacterial cells without damaging human cells
Can antibiotics kill viruses
No because viruses reproduce inside the cells is difficult to produce drugs that can destroy viruses without damaging body cells
Why don’t we culture bacteria at 37°C in the school lab
This is the human body temperature so any bacteria which grow at this temperature would be likely to be able to infect people and cause harm
How do you grow bacteria
Sterilise the inoculating loop by passing it over a Bunsen burner until it is red hot
Dip the sterelised loop in a suspension of bacteria and and use it to make zigzag streaks across the surface of the agar jelly
Seal the lead on the petri dish dish with adhesive tape up to prevent microorganismsfrom the air contaminating the culture
Why is it important not to use antibiotics too frequently
To prevent more antibiotic resistant strains appearing
What is an antigen
A unique protein on the surface of the cell that identifies it
What is an antibody
A chemical made by the white blood cells that target specific antigens
