Chapter 4 - Health, Disease And Defence Flashcards
State the WHO definition of health.
Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.
Define Disease.
A disorder of structure or function in a human, animal, or plant, especially one that produces specific symptoms or that can effect a specific location.
What are the four components of bllod?
- Red Blood Cell
- White Blood Cell
- Platelets
- Plasma
What is the function of a Red Blood Cell?
Carry Oxgen
What is the function of a White Blood Cell?
Protect the body against disease.
What are the two main types of White Blood Cells?
Phagocyte and Lymphocyte
What do Lymphocytes do?
Produce antibodies that kill the microbe.
What do Phagocytes do?
The White Blood Cell first receives a chemical signal when a pathogen has entered the body. When the pathogen is in sight, they flow around the pathogen, enclosing it in a sac. Digestive enzymes are poured into the sac and the pathogen is destroyed.
What is the function of a platelet?
Prevent bleeding by forming scabs.
What is the function of plasma?
Carries nutrients, hormones, and proteins.
Name 3 ways microbes can get into your body.
- the mouth
- cuts in the skin
- the nose
How does a microbe enter through the mouth?
When you eat food there is a chance there will be harmful microbes on it. The food will be swallowed and enter the stomach. Inside the stomach is hydrochloric acid, which is highly concentrated and will kill them.
How do microbes enter the body through the skin?
When you cut your skin, this leaves your blood system exposed to air. Microbes can then enter into the blood. To stop more from entering the body forms scabs to block the cut. A scan is a platelet stuck in fibrin mesh.
How do microbes enter the body through the nose?
Inside the nose, mucus is found. When a microbe enters the nose it gets stuck in mucus as its a sticky liquid. Then the microbe is either swallowed or coughed up.
Define immunity to disease.
When an antigen enters the body, it stimulates the immune system to produce antibodies. The antibodies attach, or bind themselves to the antigen and inactivate it.
Define Pathogen.
A bacterium, virus, or other micro-organism that can cause disease.
Distinguish between Active and Passive immunity.
Active - the individual makes his or her own antibodies
Passive - individual is given ready made antibodies
What is Active Natural immunity?
When the person gets the disease but survives, makes antibiotics and is now immune to further infection by the same pathogen.
What is Active Artificial immunity?
Vaccine does not cause disease but lymphocytes do produce antibodies. Person is now immune to that pathogen.
What is passive natural immunity?
When the mother’s antibodies cross placenta and are in breast milk, newborn child temporarily immune to pathogens for which mother produced antibodies.
What is Passive Artificial immunity?
Antibodies are injected into the person and they are then immune to that disease. It is used when the disease is too fast acting to deal with.
What is the cause of TB
Mycobaterium Tuberculosis is the germ that carries it.
What are the symptoms of TB
Coughing and sneezing
Likely outcome for person with TB
Death
