Conditions for life on Earth Flashcards
What happens when oxygen reacts with iron in the oceans
Form Banded Iron Formation
Why is liquid water essential for life?
Physiological solvent
Transport across membranes
Thermoregulation
Habitat
UV protection
Lubrication
Anomalous expansion on freezing
What is proxy data?
Data that paleoclimatologists gather from natural recorders of climate variability, e.g. tree rings, ice cores or ocean sediment
what are the harmful effects of UVB?
Alters genetic coding and damages skin cells directly, the genetic mutations may lead to cancer
What are archaea?
Prokaryotic, single-celled microorganisms (commonly extremophiles)
What are photoautotrophs?
Organisms that can make their own energy using light via photosynthesis
What was the first bacteria to photosynthesise?
Cyanobacteria
How does atmospheric pressure affect water?
Pressure was high enough to prevent liquid water from boiling in early development
What’s the required temperature range for life on Earth?
-15C - 115C
What distance is Earth from the sun?
152.03million km
How do the Auroras work?
Energized particles from the sun slam into the Earth’s upper atmosphere, but the magnetosphere protects us releasing photons at the collision
What affects the insolation reaching Earth?
Clouds reflect and absorb
Albedo of surfaces
Ozone layer utilizes UV radiation
What does gravity between the Earth and the moon do?
Create tides dn keeps the Earth orbit nearly upright in relation to its movement around the sun
How was the Earth formed?
About 4.6 billion years ago, gravity pulled rock fragments together, the huge amounts of energy absorbed as the rocks collided created heat and produced a ball of molten rock, the surface gradually cooled for the crust of rock
What’s the axial tilt range of Earth?
22.1 and 24.5
Currently 23.5
Why can ice prevent water from freezing?
Ice floats (9% expansion) stopping the convection current that may have cooled down the whole body of water, insulating the water underneath
What are the types of EM radiation?
Radiowaves, x-rays, gamma rays
Infrared radiation (700nm-1mm)
Visible light (380-700nm)
Ultraviolet radiation (100-400nm)
What’s a more efficient way of energy production?
Aerobic is more efficient than anaerobic because aerobic extracts most of the glucose molecules in the form of ATP
What was the food source for early bacteria?
Undersea volcanoes
What’s the equation for anaerobic respiration?
C6H12O6= C2H5OH + CO2 + ATP
What is precession?
Slow movement to change the orientation of Earth’s axis
What’s the Earth’s mass and why is it relevant to the development of life?
5.98x10^24kg (densest planet due to liquid core), this mass creates a gravity that holds the atmosphere
What was the Proterozoic?
Period of time that oxygen was building up in the atmosphere from 2.45 billion years ago till 540 million years ago
What’s the composition of the atmosphere?
Exosphere, Thermosphere, Mesosphere, Stratosphere and Troposphere
What is pollen analysis?
Identification and determination of frequency of pollen grains in peat bogs and other preservative situations as means of dating fossils and other remains
What is axial tilt?
Angle between Earth’s rotational axis and orbital axis
What factors allow us to study how and why conditions have changed?
Continental drift, ocean current, oceanic chemistry and atmospheric pressure
How did the reduction in CO2 relate to temperature?
Prevented a long-term temp rise though the brightness of the sun increased about 10% every billion years
How is carbon stored in rocks?
In slow geological processes, sediment is cemented together and turns to rock
How does the speed of rotation of Earth create suitable conditions for life?
Reduces temperature extremes
What does the magnetic field do?
Prevent biologically damaging radiation entering Earth
