Biology: Topic 8

Question 1

Definition of fossil

Answer 1

preserved remnant or impression of an organism that lived in the past

Question 2

What are the four necessary steps of the origin of inheritance?

Answer 2

• The abiotic formation of micromolecules (monomers: amino acids, nitrogeneous bases..)
• The polymerization of small molecules into polymers
  (proteins, nucleic acids..)
• The packaging of these molecules into protocells
  (precursor to cells)
• Transmission of self-replicating molecules.

Question 3

Ribozymes are..

Answer 3

RNA molecules that function as enzymes - can copy other RNA molecules.

Question 4

Radiometric dating…

Answer 4

uses changes in isotope composition

Question 5

Isotopes are:

Answer 5

same # of protons different # neutrons

Question 6

Cambrian explosion

Answer 6

“Explosion of diversity” of aquatic species
happened 535 Mya

Question 7

Permian extinction..

Answer 7

Happened 252 Mya, 96% of species went extinct. Greatest extinction of all time.

Question 8

Extinction vs Adaptice Radiation

Answer 8

After each extinction, there is a radiation that causes an explosion of diversity and forms more ecological niches. family dies —-> new family comes

Question 9

Prokaryotes

Answer 9

• 3500 Mya
• First photosynthetic prokaryotes
• Cause an increase in atmospheric oxygen

Question 10

Atmospheric oxygen

Answer 10

• 2700 Mya

Question 11

Single cellular eukaryotes

Answer 11

• 1800 Mya

Question 12

Multilcellular eukaryotes

Answer 12

• 1200 Mya

Question 13

Animals

Answer 13

• 635 Mya

Question 14

colonization of land

Answer 14

• 485 Mya

Question 15

Humans

Answer 15

• 6.5 Mya

Question 16

Bilateral symmetry

Answer 16

Complex nervous system

Question 17

Vascularization

Answer 17

Colonization of land

Question 18

Exoskeleton

Answer 18

New ecological relationship

Question 19

Mitochondria

Answer 19

Aerobic respiration in eukaryotes

Question 20

Multicellularity

Answer 20

Increase in size