B3a-infection and response: communicable diseases Flashcards
What is a communicable disease?
A disease that can be passed from one organism to another by direct contact, water or air
What is a non- communicable disease?
A disease that cannot be spread between organisms
What is an antigen?
Surface proteins found on pathogens that are recognized by white blood cells
What is a pathogen?
Micro organisms such as viruses and bacteria that cause infectious diseases in animals and plants
What are phagocytes?
A type of white blood cell that engulfs pathogens and digests them by phagocytosis
What are lymphocytes?
They recognize antigens on the surface of pathogens and produce antibodies or anti toxins.
What do viruses do?
Viruses reproduce rapidly in the body. They live and reproduce inside cells causing cell damage
What does bacteria do?
Reproduces rapidly inside the body. Bacteria may produce toxins that damage tissues and make us feel ill.
Measles (4)
Type of virus
Symptoms: Fever, red skin rash, can be fatal.
Spread by droplet inhalation from coughs and sneezes
Vaccination as a child prevents this.
HIV (4)
Type of virus
Flu like symptoms, serious damage to immune system causes when HIV develops to AIDS
Spread by sexual contact and exchange of bodily fluids
Anti- retroviral drugs and use of condoms prevent this
Tobacco mosaic virus (3)
Discoloration of leaves in a plant, affects growth due to lack of photosynthesis
Spread via gardening tools or workers hands
remove infected leaves and destroy, clean gardening equipment, wash hands
Skin defense system (2)
Hard to penetrate waterproof barrier
Glands secrete oil which kill microbes
Nose defense system (1)
Nasal hairs, sticky mucus and cillia prevent pathogens entering through the nostrils
Stomach defense system (1)
Stomach acid (ph2) kills most ingested pathogens
Trachea and Bronchi defense system (1)
Lined with mucus to trap dust and pathogens. Cillia move the mucus upwards to be swallowed.
