Immune System Lines of Defense

The immune system:

• helps the body to defend against infectious organisms and other invaders

• enables us to cope with and process our emotions

• helps us to digest food

• helps people to sense their surroundings

An infectious disease is caused by

• a pathogen entering our internal environment and either growing too much or producing substances that are harmful to our internal environment

• toxic chemicals entering our internal environment and causing cell death

• poor diet/ nutrition

• Lack of exercise

The bodies immune system has

• 3 lines of defense

• 2 lines of defense

• 1 line of defense

Which of the following help to make up the 1st line of defence?

• white blood cells, histamine

• t cells, b cells antibodies

• skin, hair, chemical secretions such as mucus, saliva and tears

• Skin, histamine

The first line of defence helps to

• prevent pathogens from entering body

• fight pathogens once they have entered the body

• remember pathogens that have previously invaded

The second line of defence helps to

• prevent pathogens from entering body

• fight all types pathogens once they have entered the body

• fight off specific pathogens, remember pathogens that have previously invaded,

The third line of defence helps to

• prevent pathogens from entering body

• fight all types pathogens once they have entered the body

• fight off specific pathogens, and remember pathogens that have previously invaded

Which is not part of the second line of defense

• Histamine

• neutrophils

• white blood cells

• lymphocytes

Inflammation is involved in the second line of defence. Which signs indicate inflammation has occurred at a sight of infection?

• swelling of the area

• increased blood flow to the area

• pain in the area

• tears are produced

Neutrophils are a type of white blood cell involved in the second line of defense. Neutrophils:

• envelope pathogens that have entered the body

• promote blood flow

• secrete antibodies

• secrete antigens