Chapter 3: Functioning Ecosystem

Question 1

What is the main source of energy that provides energy to all plants?

Answer 1

The Sun

Question 2

What is cellular respiration?

Answer 2

The process of releasing chemical energy from the bonds of glucose

Question 3

What are autotrophs?

Answer 3

An organism that can produce its own organic compounds from sunlight, water, and carbon dioxide

Question 4

What is a trophic level?

Answer 4

A level in the food chain of an ecosystem-based on feeding relationships

Question 5

What is biomass?

Answer 5

The total mass of living matter in an ecosystem

Question 6

What is photosynthetic efficiency?

Answer 6

How well a producer converts light energy into the chemical energy of carbohydrates

Question 7

What impacts a plant’s photosynthetic efficiency?

Answer 7

Availability of raw materials, sunlight temperature, light intensity, and the nature of the organism

Question 8

What is the gross primary productivity (GPP)?

Answer 8

The total organic matter produced annually in an area by photosynthesis

Question 9

What is net primary productivity?

Answer 9

The amount of organic matter made available to herbivores annually; equals gross primary productivity minus the energy required by the producers themselves

Question 10

What are heterotrophs?

Answer 10

An organism that cannot convert sunlight to useful energy, and must consume other organisms for food

Question 11

What is a biomass pyramid?

Answer 11

A pyramid diagram that shows the relative proportions of each trophic level in an ecosystem

Question 12

What is a food chain?

Answer 12

A chain of organisms where one organism occupying a trophic level is consumed by the next organism in a higher trophic level

Question 13

How much energy is passed on to the next trophic level?

Answer 13

10%, 90% is transformed by metabolism into heat energy and lost to the surrounding or remains as chemical energy

Question 14

What are endothermic animals?

Answer 14

When the internal body temperature of an organism is regulated and maintained higher than the temperature of the surroundings

Question 15

What are ectothermic animals?

Answer 15

When the internal body temperature of an organism reflects and fluctuates along with the surroundings

Question 16

What is the equation for percentage efficiency between trophic levels?

Answer 16

Percentage efficiency = net productivity of the organism / net productivity of the previous trophic level

Question 17

What are detritivores?

Answer 17

An organism, such as a worm, that consumes detritus, the dead tissues of once-living organisms

Question 18

What are decomposers?

Answer 18

An organism, such as a fungus, that grows on and absorbs nutrients from dead tissues

Question 19

What are the four main nutrient cycles?

Answer 19

Carbon cycle, Nitrogen cycle, Water cycle, and Phosphorus cycle

Question 20

What is a fundamental niche?

Answer 20

The widest potential niche that a species could ideally occupy without competitors

Question 21

What is a realized niche?

Answer 21

The actual niche that a species occupies, given the restrictions placed on it by interactions with other species

Question 22

What is resourced partitioning?

Answer 22

The creative use of space and time that reduces competition between species and allows many unique ecological niches to exist in the same area

Question 23

What is the competitive exclusion principle?

Answer 23

A key ecological principle that states that no two species can occupy exactly the same niche in an ecosystem

Question 24

What is carrying capacity?

Answer 24

The greatest density of organisms that an area or resource can potentially support

Question 25

What are the five general types of keystone species?

Answer 25

Predators, prey, plants, links, and modifiers

Question 26

What is keystone species?

Answer 26

A plant or animal that plays a unique and crucial role in the way an ecosystem functions