1- Chapter 1

Question 1

What is your microbiome?

Answer 1

The total complement of microbial cells in your body

Question 2

What is a microbial culture?

Medium?

Answer 2

Culture- collection of cells that have grown in a nutrient medium
Medium- liquid or solid nutrient mixture that contains all nutrients required for microorganism growth

Question 3

What is the cytoplasm made of?

Answer 3

Aqueous mixture of macromolecules, organic molecules, inorganic ions, and ribosomes

Question 4

Where are prokaryotic and eukaryotic cells found in the three domains: Eukarya, bacteria, and Archaea?

Answer 4

Prokaryotic cells are found in Bacteria and Archaea

Eukaryotic cells are found in Eukarya

Question 5

What is the difference between a nucleus and a nucleoid?

Answer 5

A nucleus is found in eukaryotic cells

Nucleoid is found in prokaryotic cells

Question 6

What are the three properties of all cells?

Answer 6

Metabolism
Growth
Evolution

Question 7

What are extremophiles?

Answer 7

Microbes that can live in environments much too harsh for other forms of life
Define the physiochemical limits of life

Question 8

How old is earth and how long ago did cells appear on earth?

Answer 8

Earth is 4.6 billion years old

Microbial cells appeared between 3.8 and 4.3 billion years ago

Question 9

What are nodules in legumes?

Answer 9

Nodules are structures that have bacteria that convert nitrogen in the atmosphere to ammonia through nitrogen fixation

Question 10

What are rumens and ruminants?

Answer 10

Rumens are microbial ecosystems where microbial communities digest and Ferment polysaccharide cellulose
Ruminants are animals like deer goats etc that eat the rumen stuff

Question 11

What is wastewater treatment?

Answer 11

Relies on microbes to treat water contaminated with human waste so that it can be reused or returned safely to the environment
Waterborne diseases can result from lack of wastewater treatment

Question 12

What is bioremediation?

Answer 12

Microorganisms are used to transform spilled oil and other toxic pollutants

Question 13

What is resolution in microscopes?

What is resolutions limit?

Answer 13

Ability to distinguish two adjacent objects as distinct and separate

0.2 um is limit

Question 14

What are oil immersion lenses?

Answer 14

Lenses where oil increases the light gathering ability of a lens

Question 15

Are dyes negatively or positively charged?

Answer 15

Positively charged to see the negatively charged parts of cells

Question 16

What are gram stains?
What colour are gram positive?
What colour are gram negative?

Answer 16

Render different kinds of cells different colours
Gram positive is purple violet
Gram negative is pink

Question 17

How can cells be made to fluoresce for fluorescence microscopy?

Answer 17

Cells fluoresce either because they contain naturally fluorescent substances or they’re stained with fluorescent dye

Question 18

What is differential interference contrast microscopy (DIC)?

Answer 18

Light microscopy that uses a polarizer that passed through a prism to create two beams and results in a 3D picture

Question 19

What is confocal scanning laser microscopy?

Answer 19

Computer microscope that couples a laser to a fluorescence microscope
High contrast 3D image
Scans up and down the layers of a specimen giving an image for each layer

Question 20

What is transmission electron microscopy and scanning electron microscopy?

Answer 20

TEM is used to examine cells and cell structure at high magnification and resolution
Electrons can’t penetrate cell structure well so must cut into cell to see clearly
SEM is where specimen is coated with a thin film of metal and electron beam scans back and forth presenting the structure of the cell

Question 21

Why do electron microscopes have better resolution than light microscopes?

Answer 21

Electrons have much shorter wavelengths than that of visible light and wavelength affects resolution

Question 22

What is spontaneous generation?

Answer 22

Belief that life arose spontaneously from non living materials

Question 23

What does sterile mean?

Answer 23

Free of bacteria or other living microorganisms

Question 24

What is Louis Pasteur known for?

Answer 24

Ending the controversy over spontaneous generation

Created pasteurization that preserves milk and other foods by heat treatment

Question 25

What was Robert Koch’s experiment with rats and disease transfer?

Answer 25

He found that if you took blood from a rat with anthrax and gave it to a healthy rat, it got anthrax too

Led to Koch’s postulates

Question 26

What is a pure culture?

Answer 26

A population of identical cells

Question 27

What is the enrichment culture technique?

Answer 27

Use of a growth media to favour the growth of a particular microorganism

Question 28

What is chemolithotrophy?

Answer 28

The oxidation of inorganic compounds to yield energy

Question 29

Why is RNA an excellent candidate for phylogenic analysis?

4 points

Answer 29

Universally distributed
Functionally constant
Highly conserved
Adequate length to show evolutionary relationships

Question 30

What is the phylogenic tree?

Answer 30

A diagram that depicts the evolutionary history (the phylogeny) of all cells and reveals the three domains

Question 31

What are the four groups of bacteria that make up 90% of bacteria?

Answer 31

Actinobacteria
Firmicutes
Proteobacteria
Bacteroidetes

Question 32

What phylum of archaea is found in soils and oceans? What about wetlands and the guts of animals

Answer 32

Thaumarchaeota found in oceans and soil

Methanogens found in wetlands and guts of animals

Question 33

Why are viruses not on the tree of life?

Answer 33

They are parasites that can only replicate within the cytoplasm of the host cell
They have no cytoplasmic membrane, cytoplasm and ribosomes
Cannot serve energy and do not carry out metabolic processes

Question 34

Is the power of light microscopy limited by our ability to magnify?

Answer 34

No it’s resolution not magnification

Question 35

What are the four types of light microscopy?

Answer 35

Bright field
Phase contrast
Dark field
Fluorescence

Question 36

How does phase contrast microscopy work?

Answer 36

Phase ring amplifies differences in the refractive index of cell and surroundings
Improves contrast without using stain