Adapted B6 Flashcards
What are pathogens and how do they spread
Pathogens are microorganisms that cause infectious disease. Pathogens may be viruses, bacteria, protists or fungi. They may infect plants or animals and can be spread by direct contact, by water or by air.
What do pathogens do inside the body
Bacteria and viruses may reproduce rapidly inside the body.
Bacteria may produce poisons (toxins) that damage tissues and make us feel ill.
Viruses live and reproduce inside cells, causing cell damage
Measles: symptoms, type, how is it spread
Measles is a viral disease
Symptoms: fever, red skin rash, can be fatal
Spread by inhalation of droplets from sneezes and coughs
HIV: symptoms, type, how is it spread
HIV is a virus
It attacks the body’s immune cells so it can not defeat other diseases
HIV is spread by sexual contact or exchange of body fluids such as blood when people share needles
TMV: type, symptoms, how does it work
Tobacco mosaic is a virus (TMV)
Gives a distinctive ‘mosaic’ pattern of discolouration on the leaves which affects the growth of the plant due to lack of photosynthesis
How is HIV treared
Antiretroviral drugs
Salmonella: symptoms, type, how is it spread and controlled
Bacteria
Fever, abdominal cramps, vomiting and diarrhoea
Salmonella food poisoning is spread by bacteria ingested in food or on food prepared in unhygienic conditions.
In the UK, poultry are vaccinated against Salmonella to control the spread
Gonorrhoea: symptoms, type, how is it spread, treatment
Bacteria ( STD )
Symptoms of a thick yellow or green discharge from the vagina or penis and pain on urinating Gonorrhoea is spread by sexual contact
The spread can be controlled by treatment with antibiotics or the use of a barrier method of contraception such as a condom
Rose black spot: type, symptoms, how it affects plants, how it is spread, treatment
Fungal disease
Purple or black spots develop on leaves, which often turn yellow and drop early
It affects the growth of the plant as photosynthesis is reduced
It is spread in the environment by water or wind
Rose black spot can be treated by using fungicides and/or removing and destroying the affected leaves
Malaria: type, symptoms, preventative measures
Protist
Causes recurrent episodes of fever and can be fatal
The spread of malaria is controlled by preventing the vectors, mosquitos, from breeding and by using mosquito nets to avoid being bitten
What are some examples of the human general immune system
- skin: barrier
- nose: mucus and hair
- trachea and bronchi: cilia wafts mucus up to be swallowed
- stomach: hydrochloric acid kills microbes
How do white blood cells help defend the body
White blood cells help to defend against pathogens by:
• phagocytosis
• antibody production
• antitoxin production
How do vaccines work
Vaccination involves introducing small quantities of dead or inactive forms of a pathogen into the body to stimulate the white blood cells to produce antibodies.
If the same pathogen re-enters the body the white blood cells respond quickly to produce the correct antibodies, preventing infection
What are monoclonal antibodies
Monoclonal antibodies are produced from a single clone of cells. The antibodies are specific to one binding site on one protein antigen and so are able to target a specific chemical or specific cells in the body
How are monoclonal antibodies produced
They are produced by stimulating mouse lymphocytes to make a particular antibody. The lymphocytes are combined with a particular kind of tumour cell to make a cell called a hybridoma cell. The hybridoma
cell can both divide and make the antibody. Single hybridoma cells
are cloned to produce many identical cells that all produce the same antibody. A large amount of the antibody can be collected and purified
