DoL

Question 1

How big are viruses, and cocci, and bacilli?

Answer 1

0.1um viruses
~1um cocci
~5um bacilli

Question 2

What is the optimum for a psychrophile?

Answer 2

4*

Question 3

What is the optimum for a mesophile? Give 3 examples.

Answer 3

39*
E.coli
N.meningitis
Strep.aureus

Question 4

What is the optimum for a thermophile? Give 1 example.

Answer 4

60*

Taq polymerase

Question 5

What is the optimum for a hyperthermophile?

Answer 5

88*

Question 6

When was PCR invented? By who?

Answer 6

Kary Mullis (1983)

Question 7

What are the three stages of PCR and at what temperatures do they operate?

Answer 7

Denaturing 95*
Annealing 55*
Extension 72*

Question 8

When and who first isolated insulin from the pancreas?
When and who discovered its crystal structure?
When was it first commercially available?

Answer 8

Macleod et al. (1923) isolated
Sanger (1958) crystal structure
1982 available

Question 9

Give an example for Sanger sequencing used to find sources of infections.

Answer 9

Campylobacter which causes salmonella in chickens- can check which strain this is most similar to.

Question 10

What is the cut off for DDH similarity to define a new bacterial species? What ANI does this correspond to?

Answer 10

<70% DNA-DNA Hybridisation

95% Average Nucleotide Identity

Question 11

What is Muller’s Ratchet?

Answer 11

A hazard of asexuality leading to reductive evolution. The irreversible accumulation of harmful mutations due to no recombination.

Question 12

How many introns per gene are there in euks?

Answer 12

8 introns : 1 gene

Question 13

What study showed that competence for transformation could be induced in bacteria?

Answer 13

Griffith (1928) study on Streptococcus pneumoniae in mice.

Question 14

What is an example of an important diagnostic fossil? For which time period?

Answer 14

The silica mineral skeleton formed by zooplankton, formed from the Cambrian onwards.

Question 15

How many times has multicellularity evolved in euks?

Answer 15

16-22 times.

Question 16

Which organisms have a form of locomotion in which actin filaments extend to project parts of the cell membrane? What are these projections called?

Answer 16

Rhizaria (a Euk supergroup) have pseudopods.

Question 17

What is the clade containing animals and their closest single-celled relatives?

Answer 17

Holozoa

Question 18

Name 4 types of asexual reproduction

Answer 18

Endodyogeny
Endopolygeny
Schizogony
Leukocyte transformation

Question 19

How many infections surveyed in 2013 were caused by unicellular euks?

Answer 19

> 99%

Question 20

What 3 factors does the Baltimore classification of viruses take into account?

Answer 20

Type of genetic material (ds/ss/DNA/RNA); whether this is integrated on the + (template) or - (complementary to template) sense strand; and replication mechanism

Question 21

When and who discovered the most common virus causing herpes in humans?

Answer 21

Epstein-Barr (1966) discovered the EBV

Question 22

Between what dates was the largest influenza epidemic?

Answer 22

1918-19 The ‘Spanish flu’
This killed more people than WWI
Called a pandemic since it crossed international borders

Question 23

Give an example of a virus that uses only the lytic cycle

Answer 23

The T4 phage which infects E.coli

Question 24

Name 4 prion diseases

Answer 24

BSE (mad cow disease)
Scrapies (affects sheep)
CJD- Creudzfeldt-Jakob Disease, degenerative neurological
Kuru- first neurodegenerative disease caused by an infectious agent- prion.

Question 25

Give an example of a study supporting the theory that infectious microorganisms can cause disease.

Answer 25

Louis Pasteur (1880) Germ Theory experiment.

Question 26

Name 3 examples of transmissible microbes that cause cancers.

Answer 26

HIV virus that causes cervical cancer
DFTD in Tasmanian devils (lethal)
CTVT in dogs and wolves (rarely fatal)

Question 27

Name 3 examples of chronic infections

Answer 27

TB (can be reactivated by HIV!)
Chickenpox/ shingles caused by the VZV virus
Cold sore virus- herpes simplex

Question 28

Name 2 unicellular and 2 multicellular pathogens/ infections

Answer 28

Unicellular: Thrush, athlete’s foot
Multicellular: Schistosomiasis, tapeworm

Question 29

Give an example of a species-specific bacterial endosymbiont that doesn’t show the expected genome reduction

Answer 29

Species-specific bacteria in earthworms, e.g. Verminephrobacter.
Subject to different envs of cocoon and nephridia.

Question 30

Give an example of an obligate/ primary symbiotic relationship in insects

Answer 30

Wolbachia genus bacteria are in >40% of insects
In filarial nematodes they are a strict mutualist
But in mosquitos they can even manipulate gender!

Question 31

Give 4 examples of symbionts in the guts of animals

Answer 31

Humans have 10x more microbial cells than human cells!
Ruminants use microbes to degrade cellulose
Aliivibrio bacs generate light, which is used by Hawaiian bobtail squid to eliminate their shadow at night and catch prey- during the day the squid clears out their bacterial colony.
Termites use microbes to degrade lignocellulose

Question 32

Give 3 stages in the history of detailed observation

Answer 32

Hooke (1660) Micrografia
Zeiss immersion lenses
Ruska (1931) first TEM enabled visualisation

Question 33

Give 5 stages in the history of biological classification

Answer 33

Linnaeus (1700s) binomial nomenclature, plants/animals
Haeckel (1866) protista
Chatton (1925) proks/euks
Whittaker (1959) 5 kingdoms, enucleata/monera..
Woese (1990) 3 domains, 6 kingdoms

Question 34

What are the 4 phyla of Archaea?

Answer 34

Euryarchaea (halophiles & methanogens)
Crenarchaea (marine, sulfur-dep)
Korarchaea (Yellowstone Obsidian Pool)
Nanoarchaea (1 species)

Question 35

Name 4 patterns of flagellation in bacteria

Answer 35

Monotrichous (one)
Amphitrichous (like ambidextrous)
Lophotrichous (like lobo, with tail)
Petritrichous (like petrified, hair standing up all over)

Question 36

When and who invented Gram staining?

Answer 36

Hans Christian Gram (1882)