Unit 7 Natural Selection

Question 1

When was Earth formed?

Answer 1

around 4.6 billion years ago

Question 2

When did Earth become suitable for life?

Answer 2

around 3.9 billion years ago

Question 3

When was the earliest fossil evidence?

Answer 3

around 3.5 billion years ago

Question 4

What fossils were the earliest evidence found?

Answer 4

Microfossils and Stromatolites

Question 5

Stromatolites

Answer 5

Produced by microbes (mainly photosynthesizing cyanobacteria; first fossil evidence

Question 6

Microbes

Answer 6

Form microbial films which trap mud; over time layers of mud/microbe mats can build up into a layered rock structure

Question 7

Early Earth contained…

Answer 7

Inorganic molecules

Question 8

Oparin and Haldane’s hypothesis

Answer 8

Early Earth was primarily composed of hydrogen, methane, ammonia, and water

Question 9

Who tested Oparin and Haldane’s hypothesis?

Answer 9

Miller and Urey

Question 10

What did Miller and Urey find when they tested Oparin and Haldane’s hypothesis?

Answer 10

Organic compounds and Amino Acids; organic molecules served as building blocks for macromolecules

Question 11

RNA Hypothesis

Answer 11

Proposes that RNA could’ve been the earliest genetic molecule; This helps explain precellular stage of life

Question 12

Evolution

Answer 12

the change in the genetic makeup of a population overtime

Question 13

Natural Selection

Answer 13

a process which individual that have certain traits tend to survive and reproduce at higher rates than other individual because of those traits

Question 14

Adaptations

Answer 14

inherited characteristics of organisms that enhance their survival and reproduction

Question 15

Artificial Selection

Answer 15

the selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits