The human body is well defended against infection. Sometimes pathogens like bacteria and viruses do get through, making you ill. There are physical barriers like your skin and the cilia (tiny moving hairs) and mucus that line your respiratory system. Natural defences is a branch of biology and we will look at it today.
Lymphocytes
Leucocytes
Phagocytes
Virocytes
They engulf and ingest pathogens
They expel the pathogens from the bloodstream via the liver
They produce antibodies which neutralise pathogens
They produce antitoxins to neutralise the effects of the toxins from pathogens
Antigens
Antipaths
Antibodies
Antibacts
Which of the following statements is correct?
Antibiotics work because the prevent the toxins from being poisonous to the host
White blood cells produce antigens to protect the body
Viruses cause cholera and typhoid in poor areas of the world
Mucus and cilia in the respiratory system
Hydrochloric acid in the stomach
Lysozyme (an enzyme) in tears
All three of the above
They destroy invading pathogens by eating them
They produce antibodies to destroy pathogens
They produce antitoxins that neutralise toxins from pathogens
They destroy pathogens by ingesting them
They penetrate inside the pathogen and destroy its nucleus
They penetrate inside the pathogen and change the chemical composition of the cytoplasm
They attach to the pathogens and cause them to clump together making it easy for phagocytes to find and ingest them
They attach to the pathogens and take them to the liver where they are destroyed
Edward Jenner is credited with the discovery of vaccination
Vaccines contain the antibodies needed to protect your body from infection
Each vaccine protects you from a specific disease
Some vaccines contain the pathogen that causes the disease
Phagocytes and lymphocytes
Stem cells and platelets
Macrophages and bacteriophages
Erythrocytes and monocytes
Colds and 'flu are viral infections
Cold and 'flu mutate too quickly so the antibiotics only work for a very short time
Colds and 'flu are 'superbugs' and totally resistant to antibiotics
Antibiotics cannot work fast enough to treat colds and 'flu
Wait!
Here's an interesting quiz for you.