Evidence Of Life

Question 1

What evidence helps us to predict when life started on earth

Answer 1

Stromatolites
Microfossils
Metamorphic

Question 2

At what time was life believed to have started

Answer 2

About 3.5 billion years ago

Question 3

At what point in time did the bombardment of the earth end

Answer 3

About 3.8 to 4.0 billion years ago

Question 4

Why couldn’t life survive on land

Answer 4

1. Because of the harmful UV rays which could break molecules
2. Because there was no oxygen
3. There was no ozone layer

Question 5

Where was life originally thought to Begin from

Answer 5

Shallow ponds

Question 6

What features of stromatolites helps us to predict when life started

Answer 6

1. It is identical to a mass microbes
   2.it contains both sediments and microbes
2. The upper layer of stromatolites photosynthesis while the lower layer feeds of it’s by products

Question 7

What features of microfossils help us to predict when life started

Answer 7

Some structures contain organic carbon

Question 8

What type of carbon is preferred for carbon dating

Answer 8

Carbon 12 and 13

Question 9

Why is difficult to find microfossils

Answer 9

It hard to distinguish between them and mineral structures

Question 10

At what point in time was life believed to rise and dominate the earth

Answer 10

About 100 - 500 million years ago

Question 11

Why is it not possible that life started in shallow ponds

Answer 11

Because the water wasn’t deep enough
And during evaporation the quantity reduces

Question 12

Where was life later confirmed to begin

Answer 12

Deep sea vents/ hot springs

Question 13

What is spontaneous generation

Answer 13

This is the hypothesis that life regularly arises from non living things

Question 14

What period was the earth believe to be formed

Answer 14

4.6 billion years ago

Question 15

What did Earth’s early atmosphere contain

Answer 15

CO2, CO, Nitrogen, ammonia and methane

Question 16

What’s another name for spontaneous generation

Answer 16

Abiogenesis

Question 17

Who was the first to carry out experiments to disprove spontaneous generation

Answer 17

Francesco redi

Question 18

In what year did Francesco redi carry out his experiment to disprove spontaneous generation

Answer 18

1668

Question 19

What country was Francesco redi from

Answer 19

Italy

Question 20

Why were deep sea vents hospitable for early life

Answer 20

1. The temperature
2. It had greater volume of water and
   was less likely to evaporate
3. There was greater chemical energy

Question 21

Who performed the second experiment to disprove spontaneous generation

Answer 21

Louis pasteur

Question 22

In what year did Louis pasteur perform his experiments to disprove spontaneous generation

Answer 22

1859

Question 23

What time was it believed that the earth cooled down enough to hold liquid water

Answer 23

3.8 billion years ago

Question 24

What were the first true cells

Answer 24

Prokaryotes

Question 25

Prokaryotes lacked………

Answer 25

Nucleus, mitochondria and chloroplast

Question 26

Prokaryotes were found in a rocks that were how old ………..

Answer 26

About 3.5 billion years old

Question 27

Francesco redi was an……….

Answer 27

Italian physician and poet

Question 28

Louis pasteur was a ………….

Answer 28

French scientist

Question 29

Early heterotrophic organisms fed on what??

Answer 29

Organic molecules

Question 30

Early heterotrophic bacteria fed on or organic molecules to release

Answer 30

CO

Question 31

Oxygen began to increase in the atmosphere at about………

Answer 31

2.3 billion years ago

Question 32

Oxygen was poisonous to early anaerobic organisms so they died off of………..

Answer 32

Underground/underwater

Question 33

What is endosymbiosis

Answer 33

It’s one bacteria engulfing another and passing that structure on

Question 34

Eucaryotes likely evolved because of

Answer 34

Endosymbiosis

Question 35

The modern chloroplast is a descendant of an engulfed ……….

Answer 35

Cyanobacteria