Question 1

Which of the following is not a biotic component of an ecosystem?

Accepted Answer

A) plants 
B) herbivores 
C) carnivores 
D) decomposers 
E) mineral nutrients

Question 2

A self-regulating association of living plants and animals and their nonliving physical environment is termed a(n)

Accepted Answer

A) ecosystem. 
B) ecotone. 
C) community. 
D) niche. 
E) biosphere.

Question 3

The first species to colonize previously disturbed or damaged ecosystems are called a(n)

Accepted Answer

A) sere. 
B) pioneer community. 
C) successor. 
D) establishment. 
E) symbiont.

Question 4

Continental drift separating a once continuous population is an example of

Accepted Answer

A) Lamarckian evolution 
B) punctuated equilibrium 
C) mutation 
D) vicariance 
E) orogeny.

Question 5

The environment in which an organism resides or is biologically adapted to live is called a(n)

Accepted Answer

A) ecotone. 
B) habitat. 
C) community. 
D) niche. 
E) trophic level.

Question 6

Broadly defined,the biosphere

Accepted Answer

A) consists of only terrestrial organisms,while the hydrosphere includes aquatic and marine organisms. 
B) only includes the biotic components of an ecosystem,with the abiotic components being considered part of the lithosphere,hydrosphere,or atmosphere,respectively. 
C) is more a theoretical construct than an observable sphere of study. 
D) extends from the ocean floor to an altitude of approximately 8 km (5 mi)into the atmosphere. 
E) encompasses both the lithosphere and the hydrosphere,but not the atmosphere.

Question 7

Only about ___ of the kilocalories in a trophic level is passed to the next trophic level (e.g. ,from autotroph to primary consumer).

Accepted Answer

A) 5% 
B) 10% 
C) 15% 
D) 20% 
E) 25%

Question 8

Consider a simple food chain in which a grasshopper eats grass,the grasshopper is eaten by a frog,the frog is eaten by a snake,and a burying beetle feeds on the snake after it dies.Which of the following is not correctly matched?

Accepted Answer

A) grass - producer 
B) grasshopper - herbivore 
C) frog - secondary consumer 
D) beetle - detritivore 
E) snake - primary consumer

Question 9

In food webs,toxic chemicals tend to accumulate and concentrate most in the

Accepted Answer

A) top carnivores. 
B) herbivores. 
C) omnivores. 
D) autotrophs. 
E) decomposers.

Question 10

Describe the limiting factor of an organism and how it affects this organism's distribution.

Accepted Answer

The answer of Describe the limiting factor of an organism...

Question 11

How is atmospheric nitrogen converted to a usable form in the biosphere?

Accepted Answer

A) Atmospheric nitrogen is directly available to plants and animals through the photosynthetic process and trophic relationships. 
B) It is absorbed into plants via stoma and converted within the plant to a usable form. 
C) Bacteria within root nodules of legumes chemically change the atmospheric nitrogen into nitrates and ammonia. 
D) Atmospheric nitrogen is completely unavailable to plants and animals and,as a result,synthetic fertilizers must be used. 
E) Atmospheric nitrogen combines with atmospheric moisture and a free oxygen molecule to form nitric acids (HNO3),which enters in the biosphere as mildly acidic precipitation.

Question 12

When a community is disturbed to the point that most or all of its species are eliminated,a process called ____occurs in which the area undergoes a series of changes in species composition as newer communities replace older ones.

Accepted Answer

A) rejuvenation 
B) mass extinction 
C) ecological succession 
D) patch dynamics 
E) symbiosis

Question 13

Human caused eutrophication is known as

Accepted Answer

A) oligotrophication. 
B) mesotrophication. 
C) cultural eutrophication. 
D) anthropotrophication. 
E) patch dynamics.

Question 14

The study of the distribution of plants and animals,the diverse spatial patterns they create,and the physical and biological processes that produce Earth's species richness is called

Accepted Answer

A) biology. 
B) ecology. 
C) geoarchaeology. 
D) biogeography. 
E) geoinformatics.

Question 15

Energy flows through an ecosystem along an idealized unidirectional pathway called a

Accepted Answer

A) food web. 
B) niche order. 
C) trophic cascade. 
D) bioamplifier. 
E) food chain.

Question 16

Which of the following would not be a limiting factor for a plant species?

Accepted Answer

A) soil phosphorus content 
B) daily precipitation values 
C) number of predators 
D) days below freezing 
E) water availability

Question 17

Photosynthesis converts

Accepted Answer

A) heat energy,carbon dioxide,and water into carbohydrates and oxygen. 
B) heat energy,oxygen,and carbohydrates into carbon dioxide and water. 
C) light energy,carbon dioxide,and water into carbohydrates and oxygen. 
D) light energy,oxygen,and carbohydrates into carbon dioxide and water. 
E) heat energy,carbon dioxide and oxygen into carbohydrates and water.

Question 18

Together,these three natural elements make up 99% of the Earth's biomass.

Accepted Answer

A) oxygen (O),argon (Ar),and helium (He) 
B) hydrogen (H),helium (He),and oxygen 
C) hydrogen (H),oxygen (O),and carbon (
C)  
D) carbon (
C) ,nitrogen,and helium (He) 
E) hydrogen (H),nitrogen (N),and helium (He)

Question 19

Photosynthesis involves

Accepted Answer

A) the release of stored carbon dioxide in a process using sunlight. 
B) fixation of carbon and production of glucose and oxygen. 
C) a process known as respiration. 
D) important reactions within the stems and roots of plants. 
E) the conversion of carbohydrates to energy by plants for their own uses.

Question 20

If a forest fire destroyed the vegetation in an area,but left some vestiges of the previously functioning community and the soil intact,what type of succession would follow?

Accepted Answer

A) primary 
B) secondary 
C) tertiary 
D) quaternary 
E) quinary

Exam 19: Ecosystem Essentials