Lec 2

Question 1

Features in common to all three domains were inherited from

Answer 1

LUCA

Question 2

Features common for 3 domains from LUCA: (6)

Answer 2

1.) DNA, the universal code
2.) Transcription & RNA
polymerase
3.) RNA of all types
4.) Translation
5.) Most proteins and the metabolic pathways they generate
6.) Membrane and cellular structure

Question 3

The transition of life’s ____ ______ ______ _____ to _____ ______ ___ has occurred through many stages

Answer 3

primitive primordial building blocks to advanced cellular life

Question 4

Oparin Ocean Hypothesis aka

Answer 4

“primordial soup”

Question 5

Oparin Ocean Hypothesis =

Answer 5

the primitive atmosphere was reducing (as opposed to oxygen-rich), and if there was an appropriate supply of energy, such as lightning or ultraviolet light, then a wide range of organic compounds might be synthesized.

Question 6

Wächtershäuser’s hypothesis of surface metabolism aka

Answer 6

“primordial sandwich”

Question 7

Wächtershäuser’s hypothesis of surface metabolism: (4)

Answer 7

1. ) Surfaces can concentrate organics by adsorption
2. ) Polymerization is favored on surfaces – why?
3. ) Surface chemistry is stereospecific
4. ) Activated precursors are not required

Question 8

The early Iron/Sulfur world could have driven…

Answer 8

…biosynthesis

Question 9

early Iron/Sulfur world: (4)

Answer 9

1. ) CO –> biomolecules
2. ) Methylthioacetate
   - Precursor of ATP
3. ) Pyruvate
   - An intermediate in many metabolic pathways
4. ) Alanine

Question 10

BIOLOGICAL SPECIES CONCEPT =

Answer 10

Species exist as part of a reproductive community

• Reproductive isolation: mechanism for protection of genotypes
• Speciation: process of achieving reproductive isolation

Question 11

PHENETIC SPECIES CONCEPT:

Answer 11

1. ) Numerical taxonomy
   - Species are defined on overall similarity or divergence – usually the presence or absence of a trait
2. ) Operational Taxonomic Unit (OTU)
3. ) Molecular and morphological species
   - Lots of characteristics are observed and used

Question 12

BACTERIAL SPECIES CONCEPTS:

Answer 12

1.) Phenetic species:
- High levels of similarity in biochemistry, genetics, morphology, nutrition, and
structure
2.) Genomic species:
- DNA:DNA hybridization (>70% = genomic species)
3.) Ecological Equivalents:
- Found in similar habitats; look, behave the same, but unrelated phylogenetically

Question 13

3 mechanisms Bacteria to take up DNA and incorporate it into their genome:

Answer 13

1. ) Conjugation
2. ) Transduction
3. ) Transformation