JMU BIO 245 micro exam 1

microorganisms

organisms that are too small to be seen with the unaided eye

microbe types

bacteria, archaea, algae, fungi, viruses, protozoa

Who was the father of western medicine

Hippocrates

Who was the father of scientific history

Thucydides

Inventor of first microscope

Leeuwenhoek

Pasteur's contributions

-Fermentation

-Pasteurization

-Vaccines

-Swan neck experiment

Koch's contributions

one bacteria= one disease (germ theory of disease)

Taxonomy

classification, description, identification, and naming of organisms

Linnaeus

Swedish botanist who proposed the modern system of biological nomenclature

Linnaeus's 2 kingdoms

animal and plant

who added kingdom fungi

Robert Whittaker

who added kingdoms protista and monera

Haeckel

who is credited with the 5 kingdom tree

Whittaker

Phylogeny

Evolutionary history of a species

genetics-based tree of life

Woese and Fox

Woese-Fox System of Taxonomy

Based on conserved small subunit ribosomal RNA sequences (ssu rRNA)

Analysis of these sequences revealed a separate group for the archaeabacteria called Archaea

An entirely new system was proposed based on domains

3 domains

Bacteria, Archaea, Eukarya

Binomial nomenclature

A system for giving each organism a two-word scientific name that consists of the genus name followed by the species name (Linnaeus)

types of microorganisms

Bacteria, Archaea, Fungi, Protozoa, Algae, Viruses

prokaryotes

Bacteria and Archaea

archaea

-found in extreme environments

-not typically associated with human disease

bacteria

-wide range of metabolic capabilities

-described in terms of shape

-cell walls= peptidoglycan

algae

plantlike protists whose derivatives can be used for human products

protozoa

animal-like unicellular protists

example of protozoa

malaria

fungi

A kingdom made up of nongreen, eukaryotic organisms that have no means of movement, reproduce by using spores, and get food by breaking down substances in their surroundings and absorbing the nutrients

types of fungi

yeast, mold, mushrooms

are yeasts unicellular or multicellular?

unicellular

multicellular animal parasites

Eukaryotes

Multicellular animals

Parasitic flatworms and roundworms are called helminths

Microscopic stages in life cycles

viruses

acellular microorganisms that can only live and replicate in a host cell

-need electron microscope to view bc so small

-infect all types of cells

virus genetic material

DNA or RNA, never both

bacteriology

study of bacteria

mycology

study of fungi

protozoology

study of protozoa

parasitology

study of helminths and other parasites

virology

study of viruses

immunology

study of immunity

wavelength

the distance between one peak and the next on a wave

frequency

the number of complete wavelengths within a specified time period

amplitude

height of a wave

absorbance

the amount of light absorbed by a sample

transmittance

the ability of light to pass through a medium

diffraction

light is bended or scattered from points or lines

refraction

The bending of a wave as it passes at an angle from one medium to another

refractive index

a measure of the extent to which a material slows transmission speed relative to empty space

focal length

the distance from the center of a lens to the focal point

convex lenses are used to

magnify; produces larger image bc can focus at a closer range

concave lens

used in microscopes to redirect light path

the objective lenses are what types of lenses

convex

what kind of lens is the condenser lens

concave

photons

particles of light

electromagnetic radiation (EMR)

a form of energy that exhibits wavelike behavior as it travels through space

fluorescent dyes

staining technique using special microscopes that detect chemical fluorescence due to special stains

fluorescent dyes can

absorb light of one frequency and emit light of a different frequency

magnification

the ability of a lens to enlarge the image of an object when compared to the real object

resolution

ability to tell that two separate points or objects are separate

what two things affect resolution

wavelength and numerical aperture

______ wavelengths are able to resolve smaller objects

shorter

numerical aperture

the ability of a lens to gather light

the ______ the numerical aperture, the better the resolution

higher

contrast

visible differences between the parts of a specimen

Father of Microbiology

Anton van Leeuwenhoek

Types of light microscopy

bright field, phase contrast, dark field, fluorescence

most commonly used type of microscope?

bright field; compound light

dark field microscopy

shows the bright specimen against a dark background and provides good resolution

does bright field or dark field use staining

bright field

true or false: dark field microscopy can observe live specimens

true; no staining required

fluorescence microscopy

uses a fluorescent dye that emits fluorescence when illuminated with ultraviolet radiation

fluorescent microscopes absorb energy from a _____ wavelength (UV, blue light) and emits it as _____ wavelengths (visible light)

short, longer

immunofluorescence microscopy

uses fluorescent antibodies to identify disease-causing microbes by seeing if antibodies bind to them

electron microscopy

uses electrons instead of light, the shorter wavelength of electrons gives greater resolution

what kind of lenses do electron microscopes use?

electromagnetic

electron microscopes require that the beam and specimen be in a ______

vacuum

two types of electron microscopes

transmission and scanning

transmission electron microscope

used to study the internal structure of thin sections of cells by electrons passing thru the specimen

scanning electron microscope

a microscope that produces an enlarged, three-dimensional image of an object by using a beam of electrons to scan entire surface of specimen

Scanning Probe Microscope

-uses sharp probes that pass over surface of specimen; interacting directly with it

-allows viewing at atomic level

-used for research

Two types of scanning probe microscopy

scanning tunneling microscope

atomic force microscope

what type of dye for a cation

basic/positive

what type of dye for anion

acidic/negative

simple staining

the use of a single basic stain to color a bacterial cell

differential staining

using specific stains to distinguish different types of cell.

types of stains in differential staining

gram, acid-fast, endospore

special staining

flagella, capsule, endospore etc.

gram positive cells turn what color

purple

gram negative cells turn what color

pink

microorganisms are measured in

micrometers and nanometers

spontaneous generation

hypothesis that life could arise from nonliving matter

who was the first to propose spontaneous generation

Aristotle

Redi

first to refute spontaneous generation; maggot experiment

Needham

supported spontaneous generation by showing that microorganisms grew in boiled broth

Spallanzani

disagreed with Needham; person who heated nutrients after being sealed, no microbes grew (support for biogenesis)

Pasteur's swan neck flask experiment

disproved spontaneous generation

cell theory

idea that all living things are composed of cells, cells are the basic units of structure and function in living things, and new cells are produced from existing cells

Schleiden

concluded that all plants are made of cells

Schwann

all animals are made of cells

Endosymbiotic theory

theory that eukaryotic cells formed from a symbiosis among several different prokaryotic organisms

Margulis

mitochondria and chloroplasts were descended from ancient symbiotic prokaryotes; called the Endosymbiotic Theory

Germ Theory of Disease

idea that infectious diseases are caused by microorganisms

Pasteur's contributions to germ theory

microbes responsible for fermentation and food spoilage thus could be responsible for causing infection