Biosphere- intro Flashcards
What is the higher boundary of the biosphere
There is no clear real boundary because bacteria can survive in dormant form as bioaersols even at heights above the stratosphere
What are the main products of respiration
Co2 and H2O
What does the caption exchange capacity of a soil mean
The capacity of negatively charged particles in the soil to attract positively charged ions eg nutrients
Are carbon stocks higher or lower below ground
Higher
What are the main controlling variables of fertility in soils
Soil texture, structure and porosity
Which term best describes the evolution process that resulted in a darker colour of peppered moths following the industrial revolution
Natural selection
Island formation episodes over a hotspot such as the Hawaiian islands will most likely lead to which type of speciation
Peripatric
What does the expression “mountain passes are higher in the tropics” by Janzen (1967) refer to?
Species ranges in the tropics have a narrower tolerance, therefore mountain passes are hard for species to get over ie species dispersal is lower
Quote to show the Gaia hypothesis
Lovelock and Margulis: “Gaia is just symbiosis as seen from space” — to understand the biosphere have to have some sort of perspective
Can the stratosphere still be considered part of the biosphere and why?
Bioaerosols— cryptobiotic forms are dormant but still considered part of the biosphere as still alive
What is the lower limit of the biosphere determined by?
Temperature (120 degrees Celsius methanopyrus sp.)
What percentage of the entire volume of the earths biosphere consists of water with depths greater than 1,000m
79%
What is the main factor determining how deep the ‘live’ ocean is?
Light penetration
What is entropy
A measure of disorder in a system. The higher the entropy the greater the disorder
What is Gibbs free energy?
Possibility of doing work
What type of entropy and free energy do you need for life
Low entropy
High free energy
Photosynthesis equation (basic)
Co2 + H2O —light energy— glucose and O2
Complex and correct photosynthesis equation
6CO2 + 6H2O + light energy = C6H12O6 + 6O2.
What are light reactions
Solar energy to chemical energy
Plants harvest solar energy
What cycle are dark reactions part of
Calvin cycle
What are dark reactions and what enzyme catalyses these reactions
Charged particles are made into longer chains of carbon.
Rubisco enzyme
Chlorophyll absorbs mainly.. parts of the spectrum
Red and blue
Why do atmospheric CO2 concentrations fluctuate across the year
Seasonal changes
Heterotrophic respiration is the opposite to
Photosynthesis
Heterotrophic respiration includes the Krebs cycle and ETC
