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Flashcards in Earth as a system Deck (15):

Which of the following is false

a) Natural systems are thermodynamically open systems.
b) Natural systems do not exchange mass and energy with their surroundings.
c) Internally, natural systems commonly experience steady-state disequilibrium.
d) Natural systems consist of “moving parts” (smaller systems) that are constantly feeding
back off each other.

b) Natural systems do not exchange mass and energy with their surroundings.


2. Three of the following are negative feedbacks. Which ones?

a) Glacier growth  greater albedo  lower temperature  more glacier growth
b) Body temperature rises  more sweat  body temperature drops
c) Bank account balance increases  more interest  bank account balance increases
d) Audio feedback (see figure below)
e) More solar radiation reaches Earth surface  temperature increase generates
more evaporation and clouds  less solar radiation reaches Earth surface
f) Glucose level increases  more insulin produced  glucose level drops

b, e, f


what energy drives the internal dynamics of the Earth system

Two things: (a) the Sun (solar radiation), and (b) heat generated within the Earth from
radioactive decay.


What is meant by the grey period of earth

No free oxygen in the atmosphere


What is meant by the red period of earth history

Lifeforms evolved and started
to photosynthesize. This produced oxygen, a waste product of photosynthesis. Oxygen
reacted with fresh mineral surfaces (especially iron), generating “mass rusting” (red colour).
Once the majority of fresh mineral surfaces on Earth surface became oxidized, free oxygen
started to build up in ocean and atmosphere.


What is meant by the white periods of earth history

global glaciations


what supposed proof exists for darwinian evolution

fossil record (despite crucial lack of transitional forms)
DNA records (operates on assumption that animals with large amounts of the same DNA are closely related)


Define reductionism

attempts to boil things down to their essence by developing laws and equations for them


what are some of the triumphs of the reductionist approach

Kepler's laws of planetary motion
aspirin (shows why it works)


What is the systems approach

Seeks to understand the world by observing how systems interact with each other.


what are 5 common traits of natural systems

1. Thermodynamically open
2. constant state of disequilibrium
3. feedbacks create steady state systems
4. are nested within larger scale systems made up of smaller-scale systems
5. Change over time, and have a beginning and end


Define forward problems

input variables are known, results are not


Define weight of evidence

Ideas and conclusions must be supported by multiple different sets of data in order to be considered valid


What is BIF

Banded Iron formation


what is considered to be one of the oldest plants that helped with oxygenating the earth