Ch. 2 A Brief Journey To The Microbial World

Front 1

A microscope which uses visible light to illuminate cells

Back 1

What is a compound microscope?

Front 2

Name different types of light microscopy:

Back 2

1. Bright-field
2. Phase-contrast
3. Dark-field
4. Fluorescence

Front 3

In this microscope specimens are visualized because of differences in contrast(density) between specimen and surroundings

Back 3

What is a bright-field scope

Front 4

What is the total magnification of a microscope?

Back 4

objective lens magnification X ocular lens magnification

Front 5

What is the maximum magnification on a light microscope?

Back 5

2000x

Front 6

What is resolution?

Back 6

The ability to distinguish two adjacent objects as separate and distinct

Front 7

What improves contrast in light microscopy?

Back 7

Staining

Front 8

What are dyes composed of for staining?

Back 8

Organic compounds that bind to specific cellular materials

Front 9

What are examples of basic dyes?

Back 9

Crystal violet, methylene blue, malachite green, and safranin

Front 10

How do basic dyes work?

Back 10

Basic cationic (pos) dyes bind to negatively charged components in the cell surface such as nucleic acids and polysaccharides ; specimen is stained while the background remains clear

Front 11

What is a chromophore

Back 11

a positively charged staining group

Front 12

What is a differential stain?

Back 12

Differential stains are those that render different kinds of cells different colors which seperates the bacteria into different groups

Front 13

An example of a differential stain

Back 13

the Gram stain

Front 14

What two major groups can bacteria be divided into?

Back 14

Gram positive and gram negative

Front 15

How do gram positive bacteria appear?

Back 15

purple

Front 16

How do gram negative bacteria appear?

Back 16

reddish pink

Front 17

What determines if the cell is gram positive or negative in the cell?

Back 17

The cell wall

Front 18

What do all cells have in common

Back 18

a cytoplasmic membrane, cytoplasm, and ribosomes

Front 19

What does a eukaryotic cell composed of?

Back 19

DNA is enclosed in a membrane bound nucleus
Contain organelles
Generally larger and more complex

Front 20

What occurs in the nucleus of an eukaryotic cell?

Back 20

Transcription and replication ( Rna synthesis)

Front 21

Where does translation occur in an eukaryotic cell?
(protein synthesis)

Back 21

the cytoplasm!

Front 22

What feautures does a prokaryotic cell have?

Back 22

No membrane enclosed organelles
No nucleus
DNA is in the cytoplasm
generally smaller

Front 23

A bacteria cell has a cell wall and a cytoplasmic membrant but an animal cell doesn't have a cell wall but just a cytoplasmic membrane

Back 23

true

Front 24

Very small microorganism that is not a cell; a static structure which behaves as a particle except when infecting a host

Back 24

a virus

Front 25

Is a virus an open system?

Back 25

No, viruses do not take in nutrients or expel wastes

Front 26

Viruses are unable to change or replace their parts by themselves

Back 26

true

Front 27

A virus aquires attributes of a living system such as replication only when?

Back 27

it infects a cell

Front 28

What is a bacteriophage?

Back 28

a virus of bacteria

Front 29

Do viruses contain ribosomes?

Back 29

No

Front 30

Do viruses have their own genome?

Back 30

Yes

Front 31

Viruses contain a single form of a nucleic acid?

Back 31

a DNA or a RNA

Front 32

what is a gene?

Back 32

a segment of DNA (or RNA in RNA viruses) that encodes a protein or an RNA molecule

Front 33

What is a genome?

Back 33

a cell's full complement of genes

Front 34

Prokaryotic cells generally have a single, circular DNA molecule called a

Back 34

chromosome

Front 35

Prokaryotes also may have small amounts of extra chromosomal DNA called

Back 35

plasmids

Front 36

The process of change over time that results in new varieties and species of organisms

Back 36

Evolution

Front 37

What has the comparison of ribosomal RNA sequences led to?

Back 37

The development of an understanding of how different types of organisms are related to eacher other

Front 38

what is phylogeny?

Back 38

the evolutionary relationships between organisms

Front 39

what is a plasmid

Back 39

an extra chromosomal genetic element nonessential for growth

Front 40

rrna sequencing helps conclude that

Back 40

all living things belong in one of three domains

Front 41

rrna changes very little..only if there were a major evolutionary event would rrna change

Back 41

fact

Front 42

comparative rrna sequencing has defined three domains of

Back 42

1. Bacteria(prokaryotic)
2. Archaea (prokaryotic)
3. Eukarya(eukaryotic)

Front 43

archae and bacteria are not closely related

Back 43

archaea are more closely related to eukarya than bacteria

Front 44

what is endosymbiosis

Back 44

the theory that mitochondria and chloroplasts originated from bacteria

Front 45

obtain their energy from the oxidation of organic molecules

Back 45

chemoorganotrophs

Front 46

use oxygen to obtain energy

Back 46

aerobes

Front 47

obtain energy in the absence of oxygen

Back 47

anaerobes

Front 48

obtain their energy from the oxidation of inorganic molecules (only found in prokaryotes)

Back 48

chemolithotrophs

Front 49

contain pigments that allow them to use light as an energy source

Back 49

phototrophs

Front 50

oxygenic photosynthesis

Back 50

produces oxygen

Front 51

anoxygenic photosynthesis

Back 51

does not produce oxygen

Front 52

all cells require carbon as a major nutrient

Back 52

fact

Front 53

fix carbon from co2 and use it as their carbon source

Back 53

autotroph

Front 54

primary producers which are usually autotrophs

Back 54

use chemical or light energy to produce new organic matter from CO2

Front 55

require one or more organic molecule for their carbon source and feed directly on autotrophs or live off products produced by autotrophs

Back 55

heterotrophs

Front 56

organisms that inhabit extreme environments

Back 56

extremophiles

Front 57

extremophiles habitats consist of

Back 57

boiling hot springs, glaciers, extremely salty bodies of water, and high pH environments

Front 58

all known pathogenic prokaryotes are

Back 58

bacteria

Front 59

Make up the largest phylum of bacteria

Back 59

proteobacteria

Front 60

Examples of proteobacteria

Back 60

E.Coli, Pseudomonas, and Salmonella

Front 61

Archaea tend to be

Back 61

extremophiles

Front 62

archaea grow at

Back 62

above 113 degrees C
in rumen of cows
some grow at low phs while some grow at ph 10 and above
some grow in highly saline habitats

Front 63

Two phylas of arachaea

Back 63

Euryarchaeota and crenarchaeota

Front 64

degrade organic matter anaerobically, produce methane

Back 64

methanogens

Front 65

require salt concentrations for metabolism and reproduction

Back 65

extreme halophiles

Front 66

grow in moderately high temperatures and low ph environments

Back 66

thermoacidophiles

Front 67

eukaryotic microorganisms include

Back 67

algae, fungi, protozoa, and slim molds