Long answer question

Question 1

What is one of the major “stepping stones” for life?

Answer 1

Transition from RNA to DNA

Question 2

What is important about the switch from RNA to DNA?

Answer 2

more complicated cell structures and specialisation allowing greater adaption and self-replication.

Question 3

What was a beneficial characteristic of some early forms of RNA?

Answer 3

Ability to catalyse and self replicate

Question 4

What is one accepted hypothesis for the origins of life put forward by Miller and Urey? (1952)

Answer 4

“pre-biotic soup” with life originating around ocean edge getting needed energy from lightning strike

Question 5

What apparatus did Miller and Urey use in their experiment?

Answer 5

Heat source over water
Flows past gas inlet of CH4, NH3
Passes into chamber with electrodes for spark
Cooled

Question 6

What was produced in the Miller and Urey?

Answer 6

proteins structures necessary for forming life

Question 7

When did the great oxidation event occur?

Answer 7

2.1 billion years ago start of the Proterozoic (American society for microbiology)

Question 8

What is the driving factor of the GOE thought to be?

Answer 8

Cyanobacteria

Question 9

When have cyanobacteria been present since?

Answer 9

~2.7 Ga (Leslie Orgel, 1994)

Question 10

What was the cause for a lag between the presence of cyanobacteria and the GOE?

Answer 10

Adsorption of oxygen by Iron

Question 11

What allowed for a build up of oxygen in the oceans and eventually diffuse into the atmosphere?

Answer 11

Abundance of cyanobacteria producing oxygen overcoming the sequestration rate

Question 12

What did increased oxygen in the atmosphere mean for surface conditions?

Answer 12

Made more hospitable for terrestrialisation

Question 13

What was the effect of the GOE on Earths atmopshere?

Answer 13

pre-event= mainly nitrogen and methane
Post-event= Methane replaced by Oxygen (N78 O21)

Question 14

What is one of the key effects of having oxygen in the atmosphere for surface conditions?

Answer 14

Helped with production of ozone (O3) absorbing UV rays and reducing solar intensity on surface eventually producing ozone layer

Question 15

When was the ozone layer formed?

Answer 15

600 Ma (University of Albany)

Question 16

What is terrestrilisation?

Answer 16

The colonisation of land via freshwater habitats by plants and animals

Question 17

What did Roman-Palacios et al, 2022 say about terrestrilisation?

Answer 17

Most terrestrial species have freshwater ancestors

Question 18

When did terrestrialisation occur?

Answer 18

Middle Ordovician with cyanobacteria being the first but thought limited to moist environments (Wellman, 2010)

Question 19

What is the first example of a land plant?

Answer 19

Rhyniophytes (Late Silurian to Devonian)

Question 20

What does rhyniophytes look like?

Answer 20

curved thin stem with saucer on top (3 cm tall)

Question 21

At what point do examples of the modern tree start to appear?

Answer 21

Late Devonian

Question 22

What is the first example of modern tree development?

Answer 22

Progynosperms (middle to late Devonian)

Question 23

What should a sketch of Progynosperms look like?

Answer 23

Tree with trunk and branches with dark leaf canopy 10m tall

Question 24

Due to the development of larger tree species from the lower to upper Devonian what happened to substrate penetration?

Answer 24

transition from shallow penetration to deeper penetration as larger plants need a greater stabilising area and uptake for water and nutrients

Question 25

What sketch can visualise the change in substrate penetration?

Answer 25

Algeo and Scheckler 1998 Sketch- minimal penetration to some vertical elongate to hexagon to deep extensive (with trunk above)

Question 26

What is the effect of more extensive root systems?

Answer 26

greater weathering surface increasing pedogenesis

Question 27

How are roots and carbon sequestration linked?

Answer 27

Roots increase weathering Increased weathering of silica rich rocks which takes C from atmo and puts it as Calcium carbonate into water and soil

Question 28

What was another result of increased pedogenesis?

Answer 28

increased sediment flow in fluvial systems

Question 29

What was the effect of increased sediment and nutrient flow in fluvial systems?

Answer 29

Eutrophication

Question 30

What is Eutrophication according to Nixon 2012?

Answer 30

an increase in organic matter in a system

Question 31

What is the effect of eutrophication on earth systems?

Answer 31

evidnece that eutrophication lead to anoxia with bacteria using up oxygen decomposing matter

Question 32

What past evidence is there for the effect of eutrophication?

Answer 32

OAEs - ocean anoxia events such as Kellwasser in the late Devonian

Question 33

What is he evidence for OAEs?

Answer 33

black shales which indicate bottom water anoxia

Question 34

What is an example of the effect of anoxia on distribution of species?

Answer 34

Belemnites deep to surface then spread

Question 35

What is a benefit of photosynthesising plants on land?

Answer 35

Carbon sequestration into biosphere

Question 36

How does the development of land habitats make areas more hospitable?

Answer 36

Sucession and colonisation cycle making abiotic less extreme

Question 37

What does Berners Geocarb III show (1991)?

Answer 37

dramatic drop in atmo co2 linked to plant land colonisation

Question 38

What is the culmination of tree developemnt?

Answer 38

Aborescene which was a period of mass wood production

Question 39

What is the main thing from Cambrian explosion?

Answer 39

major phyla

Question 40

What evolution dominated early Cambrian?

Answer 40

calcium carbonate shells and biomineralization

Question 41

What is the significance of biomineralisation?

Answer 41

carbon sink (limestone)

Question 42

How was diversity affected by Cambrian explosion?

Answer 42

huge jump - benthic to pelagic

Question 43

What was the substrate revolution? (Bottjer et al, 2001)

Answer 43

from edicaran to soupier substrate allowing for bilaterian burrows

Question 44

How is the burgess shale konservat lagerstatte evidence of cambrian diversification? (Royal Ontario Museum)

Answer 44

anomalocaris which was apex predator originally thought to be 2 seperate species

Question 45

What proxy can be used to look at predation? (sperling 2013)

Answer 45

Link between uranium oxygen and predation More oxygen more predation

Question 46

What is an opposing idea to Sperlings oxygen predation?

Answer 46

Geobiology issue 7 volume 1 Oceanic ventallation stratified cyano to ventilated eukaryotic

Question 47

What is one of the earliest example of biomineralisation?

Answer 47

Cloudina (Ediacaran)

Question 48

What us cloudina like?

Answer 48

tube like funnel external skeleton of metazoan

Question 49

How does biomineralization affect the atmo and hydro reservoirs of carbon?

Answer 49

oceans absorb 25% of atmo carbon (UN climate) so if biomineralisers remove C from water more can be absorbed

Question 50

How did plant colonisation of land affect the landscape?

Answer 50

braided rivers with little vegetation Meandering with dense vegetation due to increased stability

Question 51

What is the introduction for the earth history long answer?

Answer 51

Life has evolved through the history of Earth. As a result of evolutionary change there has also been an environmental change brought about by evolution organisms have affected the conditions of the environment with noticeable impacts on the atmosphere, hydrosphere, and terrestrial realm.

Question 52

What is the conclusion for the earth history long answer?

Answer 52

The evolution of life on Earth has had a very influential effect on the environment and conditions on a global scale. The presence and change of life have affected both the physical landscape and the composition of both the oceans and atmosphere through time. Without the presence of life conditions on Earth would be different from those at present.

Question 53

What order am I talking about ideas in my long answer?

Answer 53

Intro Miller Urey RNA/DNA Photosynthesis (cyano) Oxygen in atmo/ GOE Trees/Roots Habitats due to trees Eutrophication (belemnites, OAEs) Cambrian explosion Substrate revolution Biomineralisation Conclusion

Question 54

How can the substrate revolution put forward by Bottjer et al 2000 be visualised?

Answer 54

By Mangano and Buatois (2014) Show translation from eidacaran predominantly surface with none in substrate or column To Cambrian stage 3 lots of vertical and horizontal burrows and anomalocaris