Chapter 3- The Biosphere

Question 1

What is ecology?

Answer 1

the study of interactions among organisms and between organisms and their environmetn, or surroundings

Question 2

What is the biosphere?

Answer 2

contains the combined portions of the planet in which all of life exists (land, water, atmosphere)

Question 3

What is a species?

Answer 3

a group of organisms so similar to one another that they can breed and produce fertile offspring

Question 4

What are populations?

Answer 4

groups of individuals that belong to the same species and live in the same area

Question 5

What are communities?

Answer 5

assemblages of different populations that live together in a defined area

Question 6

What is an ecosystem?

Answer 6

a collection of all the organisms that live in a particular place, together with their nonliving, or physical, environment

Question 7

What is a biome?

Answer 7

a group of ecosystems that have the same climate and similar dominant communities

Question 8

What is the main energy source for life on Earth?

Answer 8

sunlight

Question 9

Energy flows through an ecosystem in what direction?

Answer 9

one; from sun or inorganic compounds, to autotrophs (producers), and then to various heterotrophs (consumer)

Question 10

About how much of the energy available in one trophic level is transferred to organisms at the next trophic level?

Answer 10

10%

Question 11

What are autotrophs?

Answer 11

organisms that capture energy from sunlight or chemicals and use that energy to produce food(producers)

Question 12

What is photosynthesis?

Answer 12

The process of converting sunlight, water, and carbon dioxide into carbohydrates and oxygen

Question 13

What is chemosynthesis?

Answer 13

the process of using chemical energy to produce carbohydrates

Question 14

What are heterotrophs?

Answer 14

organisms that rely on other organisms for their energy and food supply (consumer)

Question 15

What are detritivores?

Answer 15

organisms that feed on plant and animal remains and other dead matter

Question 16

What are decomposers?

Answer 16

organisms that break down organic matter

Question 17

What is a food chain?

Answer 17

a series of steps in which organisms transfer energy by eating and being eaten (linear or one way)

Question 18

What is a food web?

Answer 18

feeding relationships among the various organisms in an ecosystem that form a network of complex interactions

Question 19

What is a trophic level?

Answer 19

each step in a food chain or food web

Question 20

What is an ecological pyramid?

Answer 20

a diagram that shows the relative amounts of energy or matter contained within each trophic level in a food chain or food web. There are three types: energy pyramids, pyramid of numbers, and biomass pyramid

Question 21

What is biomass?

Answer 21

the total amount of living tissue within a given trophic level

Question 22

What does an energy pyramid show?

Answer 22

the relative amount of energy available at each trophic level.

Question 23

What does a biomass pyramid show?

Answer 23

the amount of living organic matter at each trophic level; greatest biomass is at the base of pyramid

Question 24

What does the pyramid of number show?

Answer 24

the relative number of individual organisms at each trophic level

Question 25

How is matter used in an ecosystem?

Answer 25

It is recycled within and between ecosystems

Question 26

What are biogeochemical cycles?

Answer 26

where elements, chemical compounds, and other forms of matter are passed from one organism to another and from one part of the biosphere to another; connect biological, geological, and chemical aspects of the biosphere

Question 27

What is evaporation?

Answer 27

the process by which water changes from liquid form to an atmospheric gas

Question 28

What is transpiration?

Answer 28

the process where water enters the atmosphere by evaporating from the leaves of plants

Question 29

What are nutrients?

Answer 29

The chemical substances that an organism needs to sustain life

Question 30

Why do every living organism need nutrients?

Answer 30

to build tissues and carry out essential life functions

Question 31

How are nutrients passed through the biosphere?

Answer 31

Between organisms and the environment through biogeochemical cycles

Question 32

What is nitrogen fixation?

Answer 32

bacteria on roots of legumes converts nitrogen gas into ammonia

Question 33

What is denitrification?

Answer 33

Process where soil bacteria converts the nitrates into nitrogen gas

Question 34

What is primary productivity?

Answer 34

the rate at which organic matter is created by producers

Question 35

What is a limiting nutrient?

Answer 35

when a nutrient in an ecosystem is limited due to it being scarce or cycles very slowly

Question 36

What causes algal blooms?

Answer 36

when an aquatic ecosystem receives a large input of a limiting nutrient ( runoff from heavily fertilized fields)