Classification and Morphology of Microorganisms

Question 1

Name the five kingdoms of life.

Answer 1

Plantae

Fungi

Animalia

Protista

Monera

Question 2

What are the two domains of life?

Answer 2

Eukaryotes

Prokaryotes

Question 3

Which of the five kingdoms are part of the eukaryote domain?

Answer 3

Plantae

Fungi

Animalia

Protista

Question 4

Which of the five kingdoms are part of the prokaryote domain?

Answer 4

Monera

Question 5

What is the principle different between eukaryotes and prokaryotes?

Answer 5

The presence of a nucleus in a eukaryotic cell and its absence in a prokaryotic cell

Question 6

Besides the presence/absence of a nucleus, what main difference is there between eukaryotes and prokaryotes.

Answer 6

Eukaryotic cells have a series of complex membrane-enclosed organelles which are absent in prokaryotic cells

Question 7

What is the name of the third recently discovered domain?

Answer 7

Archaea

Question 8

What are archaea?

4

Answer 8

Organism that looks and functions like bacteria - some bacterial genes

Shares some genes with eukaryotes

Some completely unique genes

They were the first form of life on earth

Question 9

What is the order of names/titles used to systematically categorise something?
(8)

Answer 9

Domain

Kingdom

Phylum

Class

Order

Family

Genus

Species

Question 10

What is the fundamental rank in bacterial classification?

Answer 10

Species

Question 11

What is a species?

Answer 11

A group of closely related organisms

Question 12

In microbiology, what considers two organisms to be of the same species?

Answer 12

If their hereditary material is greater than 70% identical

Question 13

What does a scientific name of an organism consist of?

Answer 13

Both its genus and species names

Question 14

Give the name of the main bacteria in the colon.

Answer 14

Escherichia coli

Question 15

What is the genus of Escherichia coli?

Answer 15

Escherichia

Question 16

What is the species of Escherichia coli?

Answer 16

Coli

Question 17

How must the scientific name of an organism be typed?

Answer 17

In italics, using a capital for the first letter of the genus

Question 18

How can a scientific name be abbreviated?

Answer 18

By referring to the genus with a capital letter

e.g. E.coli

Question 19

Where do most organisms get their names from in microbiology?
(4)

Answer 19

The scientist that first reported it

The location of the organism

The associated disease

The morphology

Question 20

List the six main parts of a bacterial cell.

Answer 20

Cytoplasm

Chromosome

Ribosomes

Plasmid

Cytoplasmic membrane

Cell wall

Question 21

What organelles does a eukaryotic cell have that a bacterial cell doesn’t?
(7)

Answer 21

Endoplasmic reticulum

Nucleus

Nucleolus

Nuclear membrane

Golgi apparatus

Mitochondrion

Chloroplast

(also has cytoplasmic membrane, cytoplasm, ribosomes)

Question 22

How big are bacterial cells?

Answer 22

About 1-5 microns (um)

And about 1 um wide

Question 23

How small are viruses?

Answer 23

0.25-0.025 um

Question 24

How big are eukaryotic cells?

Answer 24

10 um but some can several hundred um long

Question 25

List the six main advantages to a bacteria for being small.

Answer 25

Rapid growth rate Accelerated cellular metabolism Nutrients and waste products pass more readily into and out of a small cell Develop large cell populations - high rate of mutations Adapt readily to changing environmental conditions Evolve rapidly

Question 26

What are the 3 forms of bacteria?

Answer 26

Bacilli Cocci Spirochetes (rigid) or spirilla (flexible)

Question 27

Name four different arrangements of cocci

Answer 27

Diplococci - two in groups Tetrads = four or eight in groups Streptococci - chains Staphylococci - cocci in clusters

Question 28

Give an example of a diplococci bacteria.

Answer 28

Neisseria gonorrhoeae

Question 29

What disease does neisseria gonorrhoeae cause?

Answer 29

Gonorrhoeae

Question 30

Give an example of a streptococci bacteria.

Answer 30

Streptococcus pyogenes

Question 31

What disease does streptococci pyogenes cause?

Answer 31

Boils

Question 32

Give an example of a staphylococci bacteria.

Answer 32

Staphylococcus aureus

Question 33

What disease does staphylococcus aureus cause?

Answer 33

Boils

Question 34

Give an example of a tetrad bacteria.

Answer 34

Micrococcus luteus

Question 35

What disease does micrococcus luteus cause?

Answer 35

It is rarely pathogenic

Question 36

Name four dyes commonly used to stain bacteria.

Answer 36

Methylene blue Crystal violet Safranin Carbol fuchsin

Question 37

How do dyes stain bacteria?

Answer 37

Dyes have a positive charge and are attracted to the overall negative charge of bacterial cells

Question 38

What are differential stains?

Answer 38

Allow us to differentiate between bacterial cells based on dye colours

Question 39

Name one differential staining technique.

Answer 39

The gram stain

Question 40

What two groups does the gram stain divide bacteria into?

Answer 40

Gram negative (pink) Gram positive (purple)

Question 41

List the five main steps in gram staining.

Answer 41

Fixation Crystal violet Iodine Alcohol Counter stain with carbol fuchsin