Chemistry of Life 2 - MT1 - Part 1

Question 1

Streetlight effect

Answer 1

Is a type of observation bias that occurs when people are searching for something and look only where it is easiest
- drunkards search

Question 2

Why is there optimism about finding extraterrestrial life?

Answer 2

We have already found organisms that live in harsh environments
- eg) high temp or high salinity

Question 3

Extremophiles

Answer 3

Organisms that live in conditions of extreme environment

Question 4

Halophiles

Answer 4

Can grow in high salt waters

Question 5

Racemization

Answer 5

Is the conversion of an enantiomerically pure mixture into a mixture where more than one of the enantiomers are present

Question 6

Enantiomers

Answer 6

Mirror image molecules

Question 7

Biosignature

Answer 7

Is any evidence or indication of life, living or dead

- it can be chemical or morphological

Question 8

What is an important chemical biosignature?

Answer 8

Is the presence of liquid water

Question 9

What planet moons have water under their frozen crust?

Answer 9

Jupiter

Question 10

What are 4 examples of more complex biosignatures?

Answer 10

1. Carbohydrates
2. Lipids
3. Proteins
4. Nucleic acids

Question 11

What does it mean if you found a more complex molecule detected?

Answer 11

The more likely it is to have a biogenetic origin

Question 12

What happens at the same rate in order to obtain equilibrium?

Answer 12

Forward and back reaction

Question 13

What is earths atmosphere in?

Answer 13

Disequilibrium

Question 14

Why is earths atmosphere in disequilibrium?

Answer 14

Due to the presence of life

Question 15

What are the 2 waste gases in the atmosphere from organisms?

Answer 15

1. O2

2. CH4

Question 16

Are O2 and CH4 stable in the atmosphere?

Answer 16

No

Question 17

What would be good to look at on Mars to find life?

Answer 17

Presence of waste gases

Question 18

Mars (4)

Answer 18

1. Stable atmosphere
2. No O2
3. 96% CO2
4. Little bit of methane

Question 19

Formaldehyde

Answer 19

A colourless pungent gas in solution made by oxidizing methanol

Question 20

Methanol

Answer 20

A toxic, colourless, volative flammable liquid alcohol, can be made through distillation or oxidizing methane

Question 21

What do formaldehyde and methanol break down?

Answer 21

Methane

Question 22

What 4 things might you look for in extraterrestrial life?

Answer 22

1. Waste gases
2. Chirality
3. Isotopic ratios
4. Morphological biosignature

Question 23

What are 4 ways to study Mars for evidence of life?

Answer 23

1. Telescope
2. Uncrewed probes
3. Meteorites
4. Human crewed missions

Question 24

What are 5 examples of uncrewed probes?

Answer 24

1. Flybys
2. Orbiters
3. Landers
4. Rovers
5. Sample returen mission

Question 25

What is an example of a flyby?

Answer 25

Mariner 4

• took pictures along its path
• do this if you dont have a lot of fuel

Question 26

What is an example of an orbiter?

Answer 26

Mars express (ESA)

Question 27

What is the advantage of ESA?

Answer 27

Ongoing flow of data

Question 28

What is an example of a lander?

Answer 28

The phoenix lander (2008)

Question 29

What is an advantage and disadvantage to the phoenix lander?

Answer 29

• Advantage = light in weight

- Disadvantage = marsian atmosphere is very thin and the lander normally doesnt land safe

Question 30

What is an example of a rover?

Answer 30

Curiosity rover

Question 31

What is an example of a sample return mission?

Answer 31

Mars sample return mission (projected)

Question 32

What are 3 challenge withs the Mars sample return mission?

Answer 32

1. Blasting off of Mars is harder than the moon
2. Contaminating the instruments
3. Careful on not bringing bugs back to earth