Unit 1 Study Guide Questions and Answers Population Ecology, Community Interactions, and Ecosystems Chapters 3, 4, and class notes.

Unit 1 Study Guide

Questions and AnswersPopulation Ecology, Community Interactions, and EcosystemsChapters 3, 4, and class notes

What and How to Study

Study the PowerPoint lectures and their review questions.

Read the chapters assigned in the text.

Know the key vocabulary terms (lists at the end of each chapter and/or the glossaries).

Prepare frequently prior to the test. Review the film study questions where applicable.

These statements apply to all of the unit tests and exam.

Please Note

• The study guide question project is a work in progress, and accordingly, it is incomplete. Therefore none of the study question sets should be considered a “substitute” for a complete and exhaustive test preparation. This applies to all four of the study guide question sets.

Question 1

1. How did the community respond to the Angel Island deer problem?

Answer 1

1. How did the community respond to the Angel Island deer problem?

The community demanded that the deer be moved to the mainland, rather than be killed by hunters.

Question 2

• 2. Ultimately what happen to most of the deer?

Answer 2

• 2. Ultimately what happen to most of the deer?

They died from car impacts, dogs, coyotes, and hunters.

Question 3

• 3. What is there to be learned from the Angel Island experience?

Answer 3

• 3. What is there to be learned from the Angel Island experience?

Answers will vary….. But many will include an element of “unexpected consequences”….

Question 4

4. Define the term, population.

Answer 4

4. Define the term, population.

A group of individuals of the same species occupying a given area during a particular period of time.

Question 5

5. What is a population age structure diagram?

Answer 5

5. What is a population age structure diagram?

A demographic analytic method that divides a population into age categories (often by gender) and displays it as a graph.

Question 6

6. A population’s ______ _____ includes members of the reproductive and pre-reproductive age categories.

Answer 6

6. A population’s reproductive base includes members of the reproductive and pre-reproductive age categories.

Question 7

7. Define crude population density.

Answer 7

7. Define crude population density.

The number of individuals in some specified area of habitat.

It does not take into consideration the distribution of organisms.

Question 8

8. What are two distribution patterns (there are three)?

Answer 8

8. What are two distribution patterns (there are three)?

Clumped

Random

Uniform

(Any two will do….)

Question 9

9. State two methods of determining population size (there are three).

Answer 9

9. State two methods of determining population size (there are three).

• Direct counts

• Can sample an area, then extrapolate

• Capture-recapture method

Question 10

10. What are two rates that increase population size?

Answer 10

10. What are two rates that increase population size?

Birth rate

Immigration rate

Question 11

11. When is a zero population rate attained?

Answer 11

11. When is a zero population rate attained?

When: births + immigration = deaths + emigrationWhen: births + immigration = deaths + emigration

Question 12

12. State the Exponential Growth Equation.

Answer 12

12. State the Exponential Growth Equation.

G = rN

Question 13

13. Given G = rN, what do the symbols represent?

Answer 13

13. Given G = rN, what do the symbols represent?

• G is population growth per unit time• r is net reproduction per individual per

unit time• N is population size

Question 14

14. What type of organisms are “r strategists”?

Answer 14

14. What type of organisms are “r strategists”?

Weedy species and pioneer species

Question 15

15. State three characteristics of “r strategists”.

Answer 1515. State three characteristics of “r strategists”.• Short life• Rapid growth• Early maturity• Many small offspring.• Little parental care.• Little investment in individual offspring.

• Adapted to unstable environment.• Pioneers, colonizers• Niche generalists• Prey• Regulated mainly by extrinsic factors.• Low trophic level.

Question 16

16. Define biotic potential.

Answer 16

16. Define biotic potential.

• Maximum rate of increase per

individual under ideal conditions

Question 17

17. What is “K”?

Answer 17

17. What is “K”?

• Maximum number of individuals that

can be sustained in a particular habitat

(carrying capacity)

Question 18

18. State the logistic equation.

Answer 18

18. State the logistic equation.

G = rmax N ((K-N)/K)

Question 19

19. Given the logistic equation,

G = rmax N (K-N/K)

What do the symbols stand for?

Answer 1919. Given the logistic equation,

G = rmax N (K-N/K)

What do the symbols stand for?

• G = population growth per unit time

• rmax = maximum population growth rate per unit time

• N = number of individuals

• K = carrying capacity

Question 20

20.Refering to the former equation, what happens to G as N approaches K?

Answer 20

20.Refering to the former equation, what happens to G as N approaches K?

G (growth rate) approaches zero. The population stops growing.

Question 1

• 1.A(n) ______ is the type of place where individuals of a species typically live.

Answer 1

• 1.A habitat is the type of place where individuals of a species typically live.

Question 2

• 2. All the populations that live together in a habitat is known as the _________.

Answer 2

• 2. All the populations that live together in a habitat is known as the community.

Question 3

3. Cite three (3) factors which shape community structure. There are several.

Answer 3

3. Cite three (3) factors which shape community structure. There are several.

• Climate and topography

• Available foods and resources

• Adaptations of species in community

• Species interactions

• Arrival and disappearance of species

• Physical disturbances

Question 4

4. Define niche.

Answer 4

• 4. Define niche.

Sum of activities and relationships in which a

species engages to secure and use

resources necessary for survival and

reproduction (Its role in the environment).

Question 5

• 5. What is mutualism? Give an example.

Answer 5

• 5. What is mutualism? Give an example.

• A close relationship where both species benefit.

• Yucca moth and Yucca

Question 6

• 6. What is commensalism? Give an example.

Answer 6

• 6. What is commensalism? Give an example.

• Commensalism helps one species and has no effect on the other

• Snail and shrimp

Question 7

• 7. There are two major types of competition. What are they?

Answer 7

• 7. There are two major types of competition. What are they?

• Intraspecific: within the species

• Interspecific: between species

Question 8

• 8. How do river otters reduce intraspecific competition?

Answer 8

• 8. How do river otters reduce intraspecific competition?

• They avoid each other (partition the river).

Question 9

• 9. Define competitive exclusion principle.

Answer 9

• 9. Define competitive exclusion principle.

• When two species compete for identical resources, one will be more successful and will eventually eliminate the other.

Question 10

• 10. What is the adaptive advantage of resource partitioning?

Answer 10

• 10. What is the adaptive advantage of resource partitioning?

• Minimizes competition and allows coexistence

Question 11

• 11. How are predators different from parasites?

Answer 11

• 11. How are predators different from parasites?

• Predators are free-living; they do not take up residence on their prey.

Question 13

• 13. Name three types of parasites.

Answer 13

• 13. Name three types of parasites.

• Microparasites

• Macroparasites

• Social parasites

• Parasitoids

Question 14

• 14. Compare and contrast parasitoids and social parasites.

Answer 14

• 14. Compare and contrast parasitoids and social parasites.

• Parasitoids lay their eggs in the body of the host where they develop, mature and eventually kill their hosts.

• Social parasites lay their eggs in their host’s nest, where the host cares for the young.

Question 1

• 1. Define: ecosystem.

Answer 1

• 1. Define: ecosystem.

• An association of organisms and their physical environment, interconnected by ongoing flow of energy and a cycling of materials.

Question 2

• 2. Compare and contrast: herbivore and carnivore,

Answer 2

• 2. Compare and contrast: herbivore and carnivore.

• Herbivores eat plants and carnivores eat animals.

Question 3

• 3. Compare and contrast: omnivore and detritivore.

Answer 3

• 3. Compare and contrast: omnivore and detritivore.

• Omnivores eat both animals and plants.

• Detritivores eat the dead animal and plant material (in the soil or water).

Question 4

4. Define: biomagnification.

Answer 4

4. Define: biomagnification.

A nondegradable or slowly degradable substance becomes more and more concentrated in the tissues of organisms at higher trophic levels of a food web

Question 5

5. Which organisms are most at risk from biomagnification?

Answer 5

5. Which organisms are most at risk from biomagnification?

Predators at the high trophic levels

Question 6

6. Compare and contrast: food chain and food web.

Answer 6

6. Compare and contrast: food chain and food web.

A straight line sequence of who eats whom – food chain.

An interconnected set of food chains – food web.

Question 7

7. Compare an contrast: autotroph and heterotroph.

Answer 7

7. Compare an contrast: autotroph and heterotroph.

Autotrophs make their own food (photo or chemsynthesis)

Heterotrophs can’t make their own food. They must graze or catch their food.

Question 8

8. What is the ultimate fate of the solar energy that enters a food web?

Answer 8

8. What is the ultimate fate of the solar energy that enters a food web?

It is lost as heat.

Question 9

9. Define: bioaccumulation.

Answer 9

9. Define:Bioaccumulation. The retention of nonpolar molecules from our food or water. These molecules do not degrade very fast. Example: DDT. Others mercury and lead

Question 10

10. Which organisms are most at risk from biomagnification?

Answer 10

10. Which organisms are most at risk from biomagnification?

Top predators (carnivores)

Question 11

11. Can a predator and its parasite be on the same trophic level? Explain.

Answer 11

11. Can a predator and its parasite be on the same trophic level? Explain.

No. A parasite “dines” on its host. Therefore it is one more step from the sun (one higher trophic level).

Question 12

9. Define: biogeochemical cycle.

Answer 12

9. Define: biogeochemical cycle.

• The flow of a nutrient from the

environment to living organisms and

back to the environment.

Question 13

10. What are two cellular biochemicals that must include phosphate in their molecular structures?

Answer 13

13. What are two cellular biochemicals that must include phosphate in their molecular structures?

Phospholipids and nucleotides

Question 14

14. How can this massive eutrophication be halted and the system repaired?