BIO 260 Chapter 4 RNA
1. General Structure Characteristics of RNA: composed of nucleotides Adenine, Uracil, Cytosine,
and Guanine
- Composed of Ribose sugars
- has a hydroxyl group on the 2'C
- Nucleotides are joined by phosphodiester bonds
- Usually single stranded
- has many types of secondary structure
- easily degraded (not very stable)
2. Entropy: a measure of the disorder of a system
3. Heterotrophic Theory: prebiotic conditions on Earth (rich in carbon, hydrogen,
water, methane, and ammonia, lightning) created monomers that built up in the oceans; creating primordial/prebiotic
'soup'.
- also known as "primordial soup theory"
4. Miller-Urey Experiment: Recreated early earth conditions in a glass vase, sparked the mixture, found
monomers in the 'trap'.
-found that organic molecules can form in a strongly reducing atmosphere.
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, 5. RNA world hypothesis: hypothesis that RNA was the first nucleic acid to evolve and t hat early life was
based on RNA, rather than DNA or protein
6. RNA is unique
-can store info,
- but also act like an enzyme
- perform reactions: Evidence for the RNA world hypothesis
7. Gene Selection Theory: modern theory of evolutionary biology, says Natural Selection acts on molecules
not just living organisms:
- big v. small; inert v. reactive; longevity v. decaying; replicators v. non-replicating molecules.
-Within the replicators, selection for: 1) speed (fecundity) 2) fidelity 3) longevity
-RNA (good replicator; decays) ’DNA (more stable; still replicates;gene)
- Replicators encased in lipid layer gained protection.
2/5
1. General Structure Characteristics of RNA: composed of nucleotides Adenine, Uracil, Cytosine,
and Guanine
- Composed of Ribose sugars
- has a hydroxyl group on the 2'C
- Nucleotides are joined by phosphodiester bonds
- Usually single stranded
- has many types of secondary structure
- easily degraded (not very stable)
2. Entropy: a measure of the disorder of a system
3. Heterotrophic Theory: prebiotic conditions on Earth (rich in carbon, hydrogen,
water, methane, and ammonia, lightning) created monomers that built up in the oceans; creating primordial/prebiotic
'soup'.
- also known as "primordial soup theory"
4. Miller-Urey Experiment: Recreated early earth conditions in a glass vase, sparked the mixture, found
monomers in the 'trap'.
-found that organic molecules can form in a strongly reducing atmosphere.
1/5
, 5. RNA world hypothesis: hypothesis that RNA was the first nucleic acid to evolve and t hat early life was
based on RNA, rather than DNA or protein
6. RNA is unique
-can store info,
- but also act like an enzyme
- perform reactions: Evidence for the RNA world hypothesis
7. Gene Selection Theory: modern theory of evolutionary biology, says Natural Selection acts on molecules
not just living organisms:
- big v. small; inert v. reactive; longevity v. decaying; replicators v. non-replicating molecules.
-Within the replicators, selection for: 1) speed (fecundity) 2) fidelity 3) longevity
-RNA (good replicator; decays) ’DNA (more stable; still replicates;gene)
- Replicators encased in lipid layer gained protection.
2/5
