Sample quiz 3 answers
1- D
2- A
3- C
4- A
5- C
6- B
7- E
8- C
9- A
10- B
11- F
12. About 90% of mass and energy (these are fairly
interchangeable when discussing trophic levels and
biosphere) is lost in going from one trophic level to
the next one
above it. When we eat "low on the food chain" we will end up with
about 10% of the mass/energy, whereas if we raised rabbits on the same grain, they
would end of with about 10% of the mass/energy, and then we would end up with
10% of the rabbits mass/energy when we ate them, i.e., we would end up with
only 1% of the original grain's mass/energy!!
13. see classnotes link for Feb. 16 and 18 lectures (ie, latent heat, specific heat, cohesion, adhesion, ability
to dissolve different substances, etc).
14. TH circulation is the
"global oceanic conveyor belt". It transports heat and salt in an
attempt to even out their abundance around the world ocean. Currently, TH circulation is largely driven
by deep-water formation in the N. Atlantic near Greenland, where high density
cold, saline water sinks and begins a journey around the world ocean flowing as
a bottom current and then returning as a near-surface warm current. Any event that stops or slows deep- water
formation will slow TH-circulation and thereby slow the return flow of surface
warm water to the N. Atlantic. This
happened during the Younger Dryas as the ice sheets
melted.
15. Biotic components are mainly the
plants and animals (living organisms), whereas the abiotic
components are water, climate, nutrients (largely from soils, but also from
atmosphere), and energy (from sun)
16. ITCZ is the inter-tropical
convergence zone, sometimes known as the "heat equator". It is where
sunlight is incident most directly, so its position varies throughout the year
because the position of the noon sun is directly overhead at the geographical
Equator twice per year. In our summer,
the noon sun is directly overhead at latitudes north of the Equator, so the
ITCZ shifts northward. In our winter,
the reverse is true and ITCZ shifts south of the Equator. As the location of
most direct sunlight, the ITCZ experiences the greatest heating and it is where
air is rising as heat from the ground is transferred to the atmosphere by
conduction, thermals and latent heat. Therefore,
precipitation is also associated with the position of the ITCZ (it would cause
the "rainy" season in tropical areas that have a wet and a dry
season).
17. We did not get to this in Wed.
lecture, so this will not be on quiz 3. The terrestrial biosphere has
MUCH more biomass than the marine biosphere.
In terrestrial environments, competition for energy (sunlight) results
in large investment of photosynthetic resources into structural carbohydrates
(wood) that allow plants to try to grow upward above their neighbors and stay
there without breaking under the force of gravity on their mass. In oceans, the proportion of carbohydrates is
much lower because the producers commonly float and adjust buoyancy to move
up and down in the near surface environment.
The marine organisms therefore have a higher proportion of proteins
in their composition. Despite this large difference in biomass, the ocean
productivity is about 1/2 that of terrestrial systems. The producers
in the oceans have much shorter
average lives and recycle faster than producers on land. (This would mean
production of oxygen in the ocean would be about 1/2 that of land plants.
However, most of it does not immediately go to the atmosphere, but it dissolves in seawater
and often goes to decomposition processes before it could escape to the atmosphere)
18. American Northwest,