Prof White

Question 1

What problem was caused by Cyanobacteria beginning to photosynthesise?

Answer 1

An oxygen crisis where there was large amounts of O2, creating a problem for anaerobic life.

Question 2

Name the 7 requirements for life.

Answer 2

Liquid water, energy source, building blocks, biosynthetic pathways, separation from environment, genetic code & natural selection.

Question 3

Name 4 key steps towards life.

Answer 3

Formation of monomers, synthesis of polymers, self replicators & evolution + selection.

Question 4

What is the suggestion of the abiotic synthesis of complex organic molecules by lightning-atmosphere reactions in hydrothermal systems?

Answer 4

The Miller-Urey hypothesis

Question 5

What is the “Hot Sulfur” theory?

Answer 5

The theory that life first evolved deep in the ocean at high temperatures, potentially as thermophiles in black smokers.

Question 6

How does RNA solve the DNA and protein paradox?

Answer 6

RNA can both store information and act as a catalyst.

Question 7

What were the advantages of proteins taking over catalysis from ribozymes?

Answer 7

Proteins have more functional groups, are more stable and act as better catalysts.

Question 8

Which enzyme was required to catalyse the evolution of RNA into U-DNA?

Answer 8

Ribonuclease reductase (RNR)

Question 9

Which enzyme was required to catalyse the evolution of U-DNA into T-DNA?

Answer 9

Thydimylate synthase

Question 10

What is LUCA?

Answer 10

Last Universal Cellular Ancestor

Question 11

2 massive transfer events from bacteria to eukaryotes lead to the evolution of which organelles?

Answer 11

Chlorplast and Mitochondrian.

Question 12

What 2 behaviours cause increased spread of bacteria?

Answer 12

Antibiotic overuse & global travel.

Question 13

Which genes are essential?

Answer 13

Genes for glycolysis, ATP synthesis, DNA replication, transcription, translation and other unknown functions.

Question 14

Halophiles and methanogens are examples of what type of archea?

Answer 14

Euryarchea

Question 15

Acidophiles are examples of what type of archea?

Answer 15

Crenarchea

Question 16

Name an enzyme which existed in LUCA and exists similarly in all domains of life.

Answer 16

RNA polymerase

Question 17

What endosymbiosis event is proposed to have kick started the eukarya?

Answer 17

The capture of a proteobacterium which became the mitochondrion.

Question 18

Which group of archea can live without oxygen?

Answer 18

Methanogens

Question 19

What conditions do halophiles live in?

Answer 19

Saturated salt.

Question 20

Which group of archea are essential in carbon and nitrogen cycles?

Answer 20

Thaumarchea

Question 21

What conditions do hyperthemophiles live in?

Answer 21

High temperatures.

Question 22

What are the results when the ‘Miller experiment’ is tested?

Answer 22

Many key building blocks are produced, included 17/20 amino acids.

Question 23

Which theory suggests life came from outer space, most likely Mars?

Answer 23

Panspermia

Question 24

Which theory suggests life came from early earth with only building blocks and energy sources?

Answer 24

Darwin’s ‘Warm little pond’

Question 25

Which forms of life use RNA and U-DNA?

Answer 25

Some viruses

Question 26

Why are eukarya thought to have arisen from the TACK superphylum?

Answer 26

Many eukaryal proteins (ribosomal, actin, etc) are found in TACK family members.

Question 27

What makes archael membranes unique?

Answer 27

The use of isoprene chains, L-glycerol and ether linkage.

Question 28

Why is methanogenesis so important?

Answer 28

It allows animals to generate energy from very low energy food.

Question 29

What gives halophiles their red colour?

Answer 29

The bacteriorhodopsin in their membranes.

Question 30

What is the internal pH of acidophiles?

Answer 30

6