Viruses -are nonliving pathogen -pathogen is anything that causes a disease. -Why is it classified...
18
Viruses -are nonliving pathogen -pathogen is anything that causes a disease. -Why is it classified as being nonliving? 1. not made up of cells 2. has no organelles 3. has no metabolism
Transcript of Viruses -are nonliving pathogen -pathogen is anything that causes a disease. -Why is it classified...
Viruses-are nonliving pathogen
-pathogen is anything that causes a disease.-Why is it classified as being nonliving?
1. not made up of cells2. has no organelles3. has no metabolism
Viruses use living cells as host:-uses the host cell to make
more viruses-can not function outside the host cell
Viruses do have:-their own copy of DNA or
RNA but LACKS its own cytoplasm or ribosomes so it can not do anything with its own the DNA.
Domain?-none because it is not
living
Kingdom?-once again none because
it is not living.
General structure of a virus:
1. DNA or RNA
2. Protein Coat/capsule surrounding the
genetic material. Capsules have specific shaped “receptor sites” which attach only on to a specific type of cell.
a. Tobacco plants b. Digestive system (#1 cause of diarrhea)
c. Respiratory system
d. Bacteria
Rabies…..nerve cells
Measles….skin cells
HIV……white blood cells
19–2 Viruses
Copyright Pearson Prentice Hall
Viruses cause:
-Common colds-Chicken pox-Measles-AIDS-Warts-Cold sores-Flu
Two types of Viral Infections:
1. Virulent Viruses:-causes illnesses
immediately-Ex/ flu and common cold
2. Temperate Virus
-does not cause disease immediately but exist inside host for weeks, months or even years.
-EX/ AIDS, Warts, Cold sores
Control of viruses within our bodies: Our own defense system
Our bodies 1st line of defense:- Skin
-pathogen must enter through an opening.
Our bodies 2nd line of defense:
-White blood cells (WBC’s)-WBC’s leave blood
stream and travel to the site of infection. -WBC’s engulf the
pathogen.
Recipe for pus?????
Our bodies 3rd line of defense:
-Antibodies
-Proteins made by WBC’s-Very specific/memory cells-For each foreign body that
enters your body, your WBC’s makes a specific antibody to destroy it.
-Remain in your body and can be used at anytime.
Chicken poxMeasles
Example: Get the measles or chicken pox once, you build up antibodies which will protect you for life from getting them again.
Vaccine:-injection of a
weakened form of a virus
-stimulates body to make
antibodies-stays in body
and destroys virus if it enters
Booster shot:-
revaccination to “boost”
your immunity.
