BACTERIA & VIRUSES

MICROBIOLOGY Is the basic science that explores microscopic

organisms including viruses, bacteria, protozoa, parasites, and some fungi and algae.

The organism lack tissue differentiation and are unicellular, and exhibit diversity of form and size.

CHARACTERISTICS OF ORGANISMS1. All living things are composed of cells2. All living things perform certain chemical

processes such as growth and digestion3. All living things can reproduce4. All living things either make their own

nutrients or ingest nutrients from the environment

5. All living things respond to stimuli such as light and touch

Viruses, bacteria, fungi, and parasites may infect the human body and interfere with normal body functions.

WHAT ARE VIRUSES?A virus is a non-cellular

particle made up of genetic material and protein that can invade living cells and reproduce.

A person can catch a cold many times because there are many varieties of cold virus that cause similar symptoms

VIRUSES Are not considered to be alive

but they affect living things. With the ability to reproduce,

viruses lack nearly every characteristic of life

Need a host cell Not composed of cells Do not respond to stimuli Do not use energy for growth

and development Need electron microscope to

see

TYPES OF VIRUSES AIDS Lyme disease Bacterial meningitis Leprosy

DISEASE Any change that disrupts the normal

function of one or more body systems.

Noninfectious diseases: Diseases caused by exposure to certain chemicals or traits that are inherited.

Infectious diseases: Diseases caused by a pathogen (any microbe that causes disease.)

DISEASES CAUSED BY VIRUSES Cause disease by either

damaging or killing cells First attaches itself to a healthy

cell and then injects its DNA or RNA into cell

Then replicates once inside infected cell

No Cure, just prevention with vaccine.

Vaccines: a substance introduced into the body to stimulate the production of chemicals that destroy specific viruses or bacteria..

HOW INFECTIOUS DISEASE SPREAD

Infectious disease can be spread through:

1. contact with an infected person ex: Influenza (V) 2. contact with a contaminated object ex: Athleteis foot (F) or Influenza (V) 3. contact with an infected animal ex: Lyme Disease (B): Bite from infected tick contact with an environmental source.

BACTERIA Are small organims constiting of one cell that

lack chlorophyll Except for viruses they are the smallest living

things on earth Bacteira are found everywhere, in the air,

soil. Water, and inside of your body and skin. They multipy very rapidly and from colonies

of millions or even billions witin a space as small as a drop of water.

Classified 4 ways (spherical, rodlike, spiral, or corkscrew.

DISEASES CAUSED BY BACTERIA Use antibiotics to cure bacterial

infections Antibiotics or a chemical that can kill

bacteria without harming a person’s cell Bacteria can develop a resistance to

antibiotic and will no longer kill This is what happens when you do not

take medicine completely

VECTORS HELP SPREAD DISEASE Are mechnaims

(other then people) that spread disease without getting itself sick.

Rats, ticks, mosquitios, and soil are examples.

An infectious disease is one that can be passed from one

DISEASES CAUSES BY PROTISTS the protists that

cause each of these diseases are caused by parasites

Parasite is an organism that takes nourishment or habitat from another organism

Most cases do not kill the host

Examples Dysentery Malaria *

EPIDEMIC Is an outbreak of a

disease that affects a disproportionately large number of individuals within a population, community, or region at the same time

PANDEMIC Is an epidemic of an

infectious disease that is spreading through human populations across a large region, continent,, or even worldwide.