Week 2

Question 1

Morphology

Answer 1

Cell size and shape.

Question 2

Why is shape useful?

Answer 2

useful for distinguishing different microbial
cells

Question 3

Micrometer

Answer 3

(μm or micron) is one-millionth of a meter in length.

Question 4

What sizes are prokaryotic ranging between

Answer 4

Ranging between 0.5 and 10 in μm length, but prokaryotic cells can vary widely in size.

Question 5

Smallest and largest prokaryotic

Answer 5

The smallest prokaryotic cells are about 0.2 μm in diameter and the largest can be more than 600 μm long.

Question 6

Size range of eukaryotic cells

Answer 6

Between 5 and 100 μm in length

Question 7

Smallest and largest eukaryotic size

Answer 7

The smallest eukaryotic microorganism known is about 0.8 μmin diameter
* The largest eukaryotic cells can be many centimeters in length.

Question 8

What is cell size influenced by

Answer 8

cell structure

Question 9

how do eukaryotic cells transport things

Answer 9

actively transport mlcls and macromlcls within the cytoplasm

Question 10

how do prokaryotic cells transport things

Answer 10

Rely on diffusion for transport through the cytoplasm and this
limits their size.

Question 11

when does the rate of diffusion increase

Answer 11

as the square of the distance
traveled

Question 12

Epulopiscium fishelsoni

Answer 12

found in the gut of the surgeonfish, can be more than 75μm wide and 600μm long.

Question 13

How many genomes does Epulopiscium fishelsoni have

Answer 13

has more than 10,000 copies of its genome distributed throughout its cytoplasm, thereby preventing diffusional limitation between the genome and any region of the cytoplasm.

Question 14

Thiomargarita

Answer 14

The sulfur-oxidizing chemolithotroph
* about 750 μm in diameter

Question 15

What does the S/V ratio control

Answer 15

• How fast it grows (its growth rate)
• Shape

Question 16

what does cellular growth rate depend on

Answer 16

on the rate at which cells
exchange nutrients and waste products with their environment.

Question 17

Coccus

Answer 17

A cell that is spherical or ovoid in morphology (plural, cocci).

Question 18

Rod or a bacillus

Answer 18

A cylindrically shaped cell (plural, bacilli)

Question 19

Spirillum

Answer 19

A spiral-shaped cell (plural, spirilla)

Question 20

Vibrio

Answer 20

A cell that is slightly curved and comma-shaped.

Question 21

Spirochete

Answer 21

A special kind of organism that has a spiral shape but which differs from spirilla because the cells of spirochetes are flexible, whereas cells of spirilla are rigid.

Question 22

Appendages

Answer 22

such as stalks and hyphae, are used by some cells for attachment or to increase surface area.

Question 23

Diplococci

Answer 23

cocci occur in pairs

Question 24

Streptococci

Answer 24

form long chains

Question 25

Tetrads or sarcinae

Answer 25

occur in three-dimensional cubes,

Question 26

Staphylococci

Answer 26

occur in grapelike clusters

Question 27

Filamentous bacteria

Answer 27

long, thin, rod-shaped bacteria that divide terminally and then form long filaments composed of many cells attached end to end.

Question 28

All known cellular organisms belong to these 3 domains

Answer 28

Bacteria Archaea Eukarya

Question 29

What kind of structure does bacteria have

Answer 29

prokaryotic cell structure Undifferentiated single cells with a length that ranges from 0.5 to 10μm. * Diverse in appearance, size, and function. * Most bacteria are unicellular * Some bacteria can differentiate to form multiple cell types and others are even multicellular (for example, Magnetoglobus).

Question 30

More than 90% of cultivated bacteria belong to one of only four phyla:

Answer 30

* Actinobacteria * Firmicutes * Proteobacteria * Bacteroidetes.

Question 31

The domain Archaea consists of five described phyla:

Answer 31

Euryarchaeota * Crenarchaeota * Thaumarchaeota * Nanoarchaeota * Korarchaeota

Question 32

Viruses

Answer 32

the most abundant microbes on Earth: the population of viruses estimated to outnumber bacterial and archaeal cells by a factor of 10.

Question 33

Virology

Answer 33

the study of viruses

Question 34

why are viruses not found on the tree of life?

Answer 34

can multiply only inside a living cell, called the host cell.

Question 35

Viruses are obligate intracellular parasites:

Answer 35

1. host cell for energy 2. metabolic intermediates 3. protein synthesis

Question 36

Virion

Answer 36

structurally intricate extracellular form

Question 37

Infection

Answer 37

Viruses cannot reproduce unless the virion itself, or in some cases its genome only, has gained entry into a suitable growing host cell

Question 38

Virions purpose

Answer 38

1. protects the viral genome when the virus is outside the host cell 2. proteins on the virion surface are important in attaching it to its host cell.

Question 39

Lytic pathway

Answer 39

The virus may replicate and destroy the host in a virulent infection via a lytic pathway

Question 40

Lysogenic Pathway

Answer 40

the host cell is not destroyed and the viral genome becomes part of the host genome.