Role of Microorganisms in Disease

What is a microorganism/microbe?

An organism too small to see with the naked eye

What is classified as a microorganism? (5)

bacteria, viruses, fungi, protozoa, or animals

What is a parasite?

A microbe that isn't free ^{(lives on or in a host)}

What is a host?

A larger organism that a parasite lives in/on

What is a pathogen?

An infectious agent that causes disease

What are bacteria? (cell type, what can some cause)?

prokaryotic (no nucleus) organisms; some cause disease (like tuberculosis and meningitis)

What is a virus?

A noncellular entity with a DNA/RNA core in a protein coat ^{(not considered a living thing)}

What are protozoans/protists? What is significant about them (3)

Unicellular eukaryotes; largest group of organisms by number, biomass, and diversity

What is fungi? What is their functions (3)?

Eukaryotic organisms that absorb organic material as decomposers, symbionts, or parasites

What are helminths? Are they large enough to see with the naked eye?

Parasitic worms; yes (e.g., tapeworms, roundworms)

What is an infectious/communicable disease?

A disease that spreads from one person to another

What is a non-infectious disease

A disease that can't be transmitted directly from person to person (e.g., cancer, diabetes)

Who invented the first microscope? When did he?

Anton van Leeuwenhoek; 1600s

What is a compound microscope? What are the two lenses?

A microscope with two lens sets; ocular and objective lens

Describe a prokaryotes DNA?

singular and circular DNA (still double stranded)

How to prokaryotes replicate/divide?

binary fission

Do prokaryotes have a nucleus?

no

What is resolution (in microscopy)?

Image clarity; inversely related to the wavelength of illumination used

What is a light microscope?

A microscope that uses visible light to produce an image

What are the six types of light microscopes? (6)

Bright-field, dark-field, phase contrast, fluorescence, confocal scanning laser (CSLM), and differential interference contrast (DIC)

What is an electron microscope?

A magnification instrument that forms an image using a high-speed beam of electrons

What is a TEM (transmission electron microscope)?

An electron microscope that passes electrons through a thin specimen to form an image

What is a SEM (scanning electron microscope)?

An electron microscope that scans a specimen's surface with electrons to form a 3D-like image

How do infectious diseases commonly spread? (4)

Direct contact, body fluids, respiratory droplets, or airborne particles