B3: infection and response Flashcards
Pathogens
- Microorganisms that enter the body and communicable cause disease that spread to easily
- Animals and plants can be infected
- release toxins and attack cells
Bacteria
- Very small Cells
- Reproduce rapidly inside your body
- Produce toxins - making you ill
- Damage your cells and tissues
Viruses
- Are NOT cells
- Reproduce rapidly
- Live inside your cells and replicate themselves
- Take I’ve hosting cells
Protists
- Eukaryotes cell
- Some are parasites
- Often transferred to the organism by a vector which doesn’t get the disease it’s self e.g. mosquito
Fungi
- Grows and penetrates the human skin and surface of plants causing disease
- Spread by spores
How are pathogens spread?
- Water - picked up by drinking or bathing in dirty water e.g. cholera
- Air - carried in the air and can be breathed in , some are carried in air droplets produce when you cough or sneeze
- Direct contact - picked up by touching contaminated surfaces , including the skin
Measles
- Viral disease
- Spread by droplets from and infected persons sneeze or cough
- Develop red skin rash and signs of fever
- Can be fatal if there are complications - pneumonia or encephalitis
- Most people are vaccinated
HIV
- Is a virus
- Spread by sexual contact or exchanging body fluids such as blood
- Cause flu-like symptoms for a few weeks then the person doesn’t experience any symptoms for many years - during this time HIV can be controlled with antiretroviral drugs stopping the virus from replicating
- Attached immune cells
- Immune System is badly damaged and can’t fight off infections or cancers - late stage HIV or AIDS
TMV(tobacco mosaic virus)
- virus
- affects plants
- causes mosaic pattern on leaves of the plants - parts of of the leaves become discoloured
- discolouration means the plant can’t carry out photosynthesis ad well
- virus affects growth
Rose black spot
- Fungal diseases
- Causes purple or black spots to develop of the leaves of rose plants
- leaves can turn yellow and drop off
- less photosynthesis can happen - plants done grow very well
- spreads through the environment in water or by wind
- treated by using fungicides and by striping the plant of it’s affected leaves
Malaria
- Disease caused by a protist
- part of the protist life cycle takes place in the mosquitos- the vectors
- every time the mosquito feeds on another animals it infects a it by inspecting the protist into the animals blood vessels
- causes repeating episodes of fever
- spread can be reduced by stopping mosquitos from breeding - protected by using insecticides and mosquito nets
Salmonella
- Bacterial disease
- Causes food poisoning
- Infected people can suffer from fever , stomach cramps , vomiting and diarrhoea
- Symptoms are caused by toxins that the bacteria produce
- You can get it but eating contaminated food
Gonorrhoea
- Bacterial disease
- Sexually transmitted disease
- Passed in by sexual contact
- Symptoms are Pain when they urinate and yellow or green discharge from vagina or the penis
- Originally treated with an antibiotic but had become resistant to it
- To prevent spread people can be treated with antibiotics and should use Barrier methods of contraption
Reduce or prevention on disease
Being hygienic - simple hygiene measures, washing hands before preparing food etc
Destroying vectors - by getting rid of organisms that spread the diseases you can prevent the disease from spreading
Isolating infected individuals
Vaccination - the person can not develop the infection and then pass it on to someone else
Body’s Defense system- Skin
- Acts as a Barrier to pathogens
- Secretes antimicrobial substances which kill pathogens
- Skin looses layers and removed the bacteria with them
Body’s Defense system- Nose
•Hairs and mucus in your nose trap particles that could contain pathogens
Body’s Defense system- Teaches and bronchi
•Secrete mucus to trap pathogens
Body’s Defense system- Trachea
•Lined with cilia which waft the mucus up to the back of the throat where it can be swallowed