How old is the Earth
4.6 billion years ago
Key physical features
-Earth mass
-Distances from sun
-Orbital behaviour
-Earth’s magnetic field
What are the key physiological functions of water
-physiological solvent
-medium for transportation
What are the key environmental conditions water controls
-temperature control
- anomalous expansion of water (aquatic life) (4 degrees)
How does water control temperature
- evaporation of water absorbs heat letting plants + animals cool (transpiration + evaporation)
- Water has a high specific heat capacity
- clouds and ice have high reflectivity (albedo effect)
- water vapour is an important greenhouse gas
What are the importance of water to people
-water makes up 65-95% of all living organisms
- crucial to growth, reproduction + other metabolic functions
Importance of water to flora
- essential to photosynthesis
(essential in conversion of sunlight into energy resources in food chains)
( products used in respiration) - maintain rigidity
-medium to transport e.g dissolved gases, sugars, amino acids etc - transpiration/temperature control
What are the Economic importance of water
- energy production
-Agricultural importance
-manufacturing processes
what stats shows the uneven distribution of water around the globe
- less than 10 countries possess 60% of the worlds available freshwater supply
When + where do scienceists think life first evolved on earth?
3.5 billion years ago
in mid-oceanic ridges where hydrothermal vents developed
What is all life traced back to
LUCA
What/when did Archea form into a organism that could photosynthesis?
billions of years after life develop, Archea formed into cynobacteria
What did the oxygen react with at first?
reacted with iron in the oceans (which formed magnette)
How long ago did oxygen level start to rise in the atmosphere?
2.45 billion years ago
Oxygen in the atmopshere then created the o-zone layer which protects from harmful UBV rays… what are UBV rays + what issues do they cause
UBV rays - harmful mutagens which breaks up biological molecules
-Causing skin cancer, cataracts, leaf tissue damage
How does the ozone layer form?
What does sequestration mean?
long-term removal
What are the CO2 levels today
0.04%
Where is the carbon stored in the plant short term and long term (after they die)?
short term - plants biomass long term - geological sediments
Where is carbon stored where aquatic life from ( apart from plankton) die?
long term stores in carbonate rocks
