1.5 The origin of cells Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is abiogenesis?

A

The theory that living cells arose from non living matter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is one of the four key stages of abiogenesis to do with simple organic molecules?

A

There was non living synthesis of simple organic molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What was the non living synthesis of simple organic molecules from?

A

Primordial inorganic molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

During one of the four key stages of abiogenesis what did the simple organic molecules assemble into?

A

More complex polymers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

During one of the four key stages of abiogenesis what did certain polymers form the capacity to do?

A

Self replicate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

During one of the four key stages of abiogenesis what does the self replicating polymers enable?

A

Inheritance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

During one of the four key stages of abiogenesis what were the molecules packaged into and with?

A

Membranes with an internal chemistry different from their surroundings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What demonstrated the non living synthesis of simple organic molecules?

A

The miller-Urey experiment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What did the miller urey experiment recreate?

A

The postulated conditions of pre-biotic earth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What did miller urey use to create pre biotic earth?

A

A closed system of flasks and tubes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

In the miller urey experiment what did they do to water and why?

A

Water was boiled to vapour to show the high temperatures of earths original conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In the miller urey experiment what was the vapour mixed with and why?

A

Gases such as H2, CH4, NH3 to create an atmosphere without oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

In the miller urey experiment, what happened to the vapour exposed to gases and why?

A

An electrical charge to recreate lightning as an energy source

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

In the miller urey experiment, what happened to the mixture with an electrical discharge?

A

It was left to cool for a week

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

In the miller urey experiment, what happened after it was left for a week?

A

The condensed mixture was analysed and found to have traces of simple organic molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Name three types of conditions needed for the chemical processes that contributed to the initial formation of biological life?

A

Reducing atmosphere
High temperatures
Electrical Discharge

17
Q

Why cant cells arise independently by abiogenesis?

A

As the specific conditions needed do not commonly exist on modern earth

18
Q

What is the only way cells can be formed?

A

By the division of pre existing cells

19
Q

What is biogenesis?

A

The principle that living things only arise from other living things by reproduction

20
Q

Who is credited with the law of biogenesis?

A

Louis Pasteur

21
Q

What did Louis pasteur demonstrate?

A

Emergent bacteria growth in nutrient broths were due to contamination by pre existing cells

22
Q

In Louis Pasteurs experiment, were where broths stored?

A

In vessels with swan neck ducts

23
Q

In Louis Pasteurs experiment, why were swan neck vessels used?

A

To prevent external dust particles to pass

24
Q

In Louis Pasteurs experiment, what happened to the broths and why?

A

Boiled to kill any micro organisms present

25
Q

In Louis Pasteurs experiment, where did the growth occur?

A

If the flasks were broken open as they were exposed to the outside contaminents

26
Q

What did the louis pasteur experiment conclude?

A

That emergent bacterial growth came from external contaminants and did not spontaneously occur

27
Q

What is an endosymbiont?

A

A cell which lives inside another cell with mutual benefit

28
Q

Where is believed that eukaryotic cells evolved from?

A

Early prokaryotes that were engulfed by phagocytosis

29
Q

What happened to the engulfed prokaryotic cell?

A

Remained undigested as it contributed a new function to the engulfing cell

30
Q

Over generations, what happened to the engulfed cell?

A

Lost some of its independent utility and became an organelle

31
Q

What are two organelles suggested to have arisen via endosymbiosis?

A

Mitochondria and chloroplasts

32
Q

What is evidence that supports the extracellular origins of mitochondria and chloroplasts?

A

Membranes
Antibiotics
Division
DNA
Ribosomes

33
Q

How are membranes evidence of endosymbiosis?

A

Some organelles have double membranes

outer membrane may be vesicular in origin

34
Q

How are antibiotics evidence for endosymbiosis?

A

They are susceptible to antibiotics which indicates organelles may have bacterial origins

35
Q

How is division evidence for endosymbiosis?

A

Reproduction occurs via a fission-like process

36
Q

How is DNA evidence for endosymbiosis?

A

Has own DNA which is naked and circular like prokaryotic DNA structure

37
Q

How is ribosomes evidence for endosymbiosis?

A

Have ribosomes which are 70s in size like prokaryotes