Week 11 – Biogeography

Question 1

What is a Biome?

Answer 1

A global scale community of plants & animals.

Question 2

What are two factors that affect the distribution of biomes throughout the Earth?

Answer 2

Latitude and climate

Question 3

Name the six biomes that we defined in this course.

Answer 3

Rainforest
Desert
Savanna
Tundra
Temperate deciduous forest
Temperate grassland
Coniferous forest

Question 4

What is a habitat, and give an example of a specific animal’s habitat within an ecosystem.

Answer 4

A habitat is a natural environment within the ecosystem in which an organism lives
Ex: African elephant in African savanna

Question 5

Name the abiotic components of an ecosystem (there are three).

Answer 5

Sunlight
Precipitation/water
Soil minerals

Question 6

What is an organism’s Niche within a habitat?

Answer 6

the function or occupation of a life form
within its habitat: the organism’s adaptation to,
and interaction with its physical environment.

Question 7

What two factors play a large role in defining that niche?

Answer 7

1) Abiotic factors
2) Organism’s place in the food chain.

Question 8

What percentage of global biomass is comprised of plants?

Answer 8

82%

Question 9

What percentage of total biomass is in terrestrial environments?

Answer 9

86%

Question 10

What is the definition of Biodiversity?

Answer 10

The variety and abundance of plant and animal species in an ecosystem

Question 11

What is the definition of Net Primary Productivity?

Answer 11

Measures vegetation abundance and is able to predict all biodiversity.

Question 12

What is the Principle of Limiting Factors – and how does that relate to Net Primary Productivity and Biodiversity

Answer 12

The maximum obtainable rate
of photosynthesis is limited by
whichever basic resource of
plant growth is in the least supply:
energy (sunlight) and
moisture.

Warm climates have higher rainfall, whereas drier climates have lower rainfall/moisture

Question 13

Forests (all kinds) contain what percent of Earth’s biodiversity.

Answer 13

80%

Question 14

Which tropical forest is the Earth’s largest?

Answer 14

Amazon Rainforest

Question 15

What are three types of plant adaptations to capture available light and moisture? Be able to name an example of each.

Answer 15

Leaf form-Conifer needles also
limit water loss and damage from
cold – small size, waxy coating.

Canopy structure- a tropical rainforest has multiple levels, an open forest floor

Root system- Mangrove roots absorb oxygen and limit salt intake from brackish water

Question 16

What are Ecotones?

Answer 16

Transition from one ecosystem to another

Question 17

What are two characteristics of Ecotones?

Answer 17

High diversity of life
Buffer region for adjacent ecosystems, such as coastal mangrove forests, when catastrophic conditions strike.

Question 18

Describe the concept of Plant Succession in a plant community. Where might we see Plant Succession in progress?

Answer 18

Evolution of plant communities from simple & limited to complex & diverse
This can be seen after fires in forests

Question 19

What are the 5-6 Trophic Levels in the Food Chain?

Answer 19

Bottom to top:
Primary producers (vegetation)
Primary consumers (eat the plants)
secondary consumers (eat primary consumers)
apex predators (top of the food chain)
decomposers (consume the waste…. nutrients then used by producers)
thermodynamics- (solar energy converted to Biomass energy & heat)

Question 20

What are the First and Second Laws of Thermodynamics, and how does this affect energy flow up the Food Chain?

Answer 20

1st Law of Thermodynamics:
Energy cannot be created or destroyed – it only changes from one form to another
(Energy is transferred up the food chain. But less energy is transferred - fewer animals!)

2d Law of Thermodynamics:
When energy is transformed, there is a “loss” of energy through the release of heat.
(When animals consume, there is a loss of heat. Also, heat loss through respiration & movement by animals.)

Question 21

Name the seven biomes we have discussed in this course. Where, generally, are these biomes found in the world?

Answer 21

Rainforest (tropical and temperate)- tropical: equator, temperate: coastal areas further N. or S. of the equator

Coniferous forest- between the tundra to the north and the deciduous forest to the south

Temperate deciduous forest- mid-latitude areas

Desert- Sub-tropics; Between 15° and 35° latitude (North and South of the equator);

Tundra- Regions south of the ice caps of the Arctic

Grasslands- Mid-latitudes, with some subtropical

Shrubland- west coastal regions between
30° and 40° N. & S. latitude