TOPIC 1

Question 1

What is biological evoluation?

Answer 1

it is a change in the properties of groups of organisms over the course of generations

Question 2

What is abiogenesis?

Answer 2

refers to a theory on the origin of life. so life originated from inorganic or non-living substances

Question 3

What is biogenesis

Answer 3

refers to a theory that life originated from pre-existing living matter.

Question 4

hadeon eon (4-4.6 gya)

Answer 4

there was constant meteor bombardments, water came form ivy comets and asteroids (water as vapor) little evidence of biosignature (no life)

Question 5

archeon eon (2.5-4 gya)

Answer 5

earliest geological evidence of life, less frequent meteor bombardments, stable oceans started to form then it means that water is life. ( lands cooling down)

Question 6

what is biosignature

Answer 6

it is evidence of life in the geological record. so microbial life appeared as early as 3.8 b years soon after the planet was formesd (bacterias played a role into photosynthesis)

Question 7

what are stromatolites?

Answer 7

it is the first biosignature for which we have clear fossil evidence. it looks identical to living mats of microbes where it has layers of microbes and sediments. the top layer uses photosynthesis and lower one uses layer’s byproducts

Question 8

are stromatolites evidence of life?

Answer 8

yes because the modern stormatolites are uselful for understanding structures that were formed a long time ago

Question 9

what are microfossils?

Answer 9

it is the most convincing evidence for early microbial life is the visual appearance of microfossils. dated by age of the rock formation and show 3D pattern of cells that resemble modern cells. oldest dated at 2.0-3.45 gya (fakanebtous prokaryotes and colonial cyanobacteria). 1.2 gya fossil. cells comparable to those of modern eukaryotes such as algae

Question 10

chemical biosignature

Answer 10

organic molecule may last within rock for hundreds of millions of years.

Question 11

kerogen

Answer 11

organic substance produced by decay and transformation of living organism. ex sedimentary rock in greeland

Question 12

membrane lipids

Answer 12

hopanoid or fossil biomarker derivative found in sedimatary rock. ex hamersley basin

Question 13

the great oxidation event

Answer 13

Evolution of the first oxygenic phototrophs
Sometime between 3 – 2.1 billion years ago.
• Proliferation of cyanobacteria, Evolution of photosynthesis, Oxygenic/oxic atmosphere
Banded iron formations
• Oxidation states of minerals (iron), Alternating layers of reduced (Fe2+) and oxidized (Fe3+) iron – alternating
anoxic and oxic conditions

Question 14

evolution of eukaryotic microbes

Answer 14

Evolution of eukaryotic cells
• 2 Gya, Formation of membrane-bound organelles and nucleus
• Endosymbiotic theory
• Evolution of multicellularity- 1.2 Gya

Question 15

what is the panspermia life theory?

Answer 15

meteorites, asteroids, or comets transported the first forms of life to earth

Question 16

what is spontaneous generation model?

Answer 16

the hypothetical process by which living organisms develop from nonliving matter.

Question 17

what is the primordial/ prebiotic soup model?

Answer 17

It came from the swamp- fueled by sunlight
• Proposed by Alexander Oparin in 1924, and J. B. S. Haldane in 1929.
• Early primitive water bodies -full of complex organic material
• Methane-ammonia atmosphere
• Most widely accepted model
• Tested by Miller-Urey experiment 1950’s

Question 18

Significance of MULLER experiment

Answer 18

Amino acid, building blocks of life,