* Chapter 45

Question 1

What is biodiversity?

Answer 1

The number of species that lives in that community

Question 2

What is a habitat?

Answer 2

Aplace where an organism lives; it is characterized by distinctive physical features, vegetation, and the array of species living in it (biodiversity)

Question 3

What is a community ?

Answer 3

it is an association of interacting populations of different species living in a particular habitat

Question 4

What are the 5 factors that shape the structure of the community ?

Answer 4

1. interactions between climate and topography dictate sunlight availability, rainfall, temperature, soil composition and so on
2. availability of resources affects inhabitants
3. adaptive traits enable individuals to exploit specific resources
4. interactions of various kinds occur among the inhabitants; these include competition, predation, and mutualism
5. physical disturbances (natural or man made), immigration, and episodes of extinction affect the habitat

Question 5

What are tropics and artic enviornments? which one has a higher biodiversity and why?

Answer 5

tropics: humid,rich soil, mild temperature, sunlight available all year
artic: artic, poor soil, extreme temperatures, sunlight limited

there is more biodiversity in the tropics because tropics have an environment that favors growth for plants.
the more plants (producers) the more species that will live

Question 6

The niche of each species is defined by…?

Answer 6

the sum of activities and relationships in which it engages to secure and use the resources necessary for its survive and reproduction.
in other words, the function of species members in a community so they can survive and reproduce

Question 7

Interactions can occur between any __ species in a community and between entire communities

Answer 7

2

Question 8

Describe and provide an example for a neutral relationship

hint: 0,0

Answer 8

• neither species directly affects the other (example: eagles and grass) both are members of the community however neither is disadvantaged or advantaged

Question 9

Describe and provide an example for commensalism

hint: +,0

Answer 9

-One species benefits and the other is not affected (neutral). (Ex. Bird’s nest in a tree; the bird benefits but the tree neutral)

Question 10

describe and provide an example for mutualism

hint: +,+

Answer 10

-There is a symbiotic relationship where both species benefit (Ex. the mitochondria, chloroplast and bacteria –> the theory of endosymbosis)

Question 11

Describe and provide an example for interspecific compettion

hint: -,-

Answer 11

-When both species are harmed by the interaction (Ex. Whem embers of two different species fight and compete for resources)

Question 12

Describe and provide an example for predation and parasitism

hint: +,-

Answer 12

-When one species (predator or parasite) benefits while the other (prey or host) is harmed

Question 13

Define symbiosis

Answer 13

symbosis implies an intimate and rather permanent interdependence of the 2 species on one another for survival and reproduction

Question 14

Which specie interactions are symbiotic

Answer 14

• commensalism
• parasitism
• mutualism

Question 15

Define and provide examples for obligatory mutualism

Answer 15

• obligatory mutualism is when two species are dependent on one another. If one goes extinct the other surely will die out
  1st example: the yucca moth feeds only on the yucca plant, which is completely dependent on the moth for pollination.
  2nd: mycorrhizae: interaction of developing plant roots.
  benefit for plant is that the fungus extends the root system and growth. While the fungi gets all the food it ever needs
  Rhizbium, a nitrogen fixing bacteria forms a mutualistic relationship with the roots of some plants such as legumes. The plant gets fertilized, the bacteria gets all the glucose it needs
  3rd: theory of endosymbosis

Question 16

What is the main difference between predators and parasites

Answer 16

• predators never lives next to prey, predator kills prey immediately for resources
• parasites do no want to kill their host immediately since the host is the parasite’s source of residence and food. parasites usually kill slowly

Question 17

_______ tends to favor parasite and host adaptions that promote some level of mutual tolerance and less-than-lethal effects

Answer 17

natural selection

Question 18

Seldom rapid death results when a parasite attacks a host. It may happen if …?

Answer 18

the number of parasites overwhelm the host’s defenses

Question 19

Parasites that live on the surface of the host are called..?

Answer 19

Ectoparasites. An example of this would be Lice

Question 20

Parasites that live within the host’s body are called..?

Answer 20

Endoparasites. An example of this would be tape worms

Question 21

What do microparasites include?

Answer 21

-bacteria, viruses, and protistans

Question 22

What do macroparasites include?

Answer 22

-flatworms, nematodes, and small arthropods

Question 23

What type plant parasites are Hemiparasites? give an example

Answer 23

they are photosynthetic plant parasites.
Mistletoe is an example. They take residence in the tip of tall trees for light energy which allow them to grow and reproduce at a high rate

Question 24

What type plant parasites are Holoparasites? give an example

Answer 24

they are non-photosynthetic plant parasites.

Broomrape is an example. They need a host that produces glucose (food source) (light independent stage produces glucose)

Question 25

What are social parasites and give an example.

Answer 25

Social parasites depend on the social behavior of another to complete the life cycle.
For example: cowbirds lay their eggs in the nest of other birds, which unknowingly incubate and hatch cowbirds’ eggs. Cowbirds use somebody else’s resources to complete the life cycle

Question 26

Competition within a population of the same species is also called …?

Answer 26

intraspecific; the type of competition is usually fierce and may result in depletion of a resource because species feed at the same time and eat the same food.

Question 27

Interspecific competition is between …?

Answer 27

two different species. This type of competition is less intense because requirements are less similar between the competitors

Question 28

(regardless of being inter- or intraspecific competition)

what is exploitation competition ?

Answer 28

when all individuals have equal access to a resource but differ in their ability (speed or efficiency) to exploit that resource.
Ex. bees send message to other bees to get nectar.

Question 29

(regardless of being inter- or intraspecific competition)

What is interference competition?

Answer 29

is when some individuals limit others’ access to the resource. (one species will claim the resource). Ex. finch claims bread, doesn’t let other species of birds get to it

Question 30

allelopathy is the type of interference competition between ____

Answer 30

competition between plants. in allelopathy, a plant produces/ releases poison into the air. poison molecules stop germination and growth so no individuals can use those resources (even if from same species).

Question 31

what does competitive exclusion suggest?

Answer 31

it suggests that species that use resources efficiently will drive the other species out. This happens when competitors use the same resources. Hence, complete competitors cannot coexist indefinitely

Question 32

when competitors’ niches do not overlap as much, the _____ is more probable

Answer 32

coexistence

Question 33

differences in ______ will give certain species the competitive edge

Answer 33

adaptive traits

Question 34

What is resource partitioning?

Answer 34

when similar species share the same resource in different ways
For example, 9 species of large and small pigeons live in the rain forests of new guinea, each with its own role (niche) in the forest

Question 35

1. what is ecological succession?
2. Who are the pioneer species ?
3. What is a climax community?

Answer 35

1-the predictable developmental sequence of species in a community (species so not show up at the same time)

2-they are the first to colonize an area, followed by more competitive species. They begin the community development

3-the most persistent array of species that results after some lapse of time.

Question 36

What happens in primary succession?

-what do the pioneer species do?

Answer 36

• happens in an area that was devoid of life (Ex. volcanic island - has no organic substances; so moss and lichen have enzymes to extract nutrients and make the soil richer–> plants grow–>more species)
• the pioneer species help improve soil fertility; they are usually small, low-growing plants with a short life cycle and an abundance of seeds

Question 37

Gradually other, usually _____, species join or replace the pioneer species

Answer 37

larger

Question 38

In secondary succession a community _____ itself to a climax state after a ____

Answer 38

reestablishes; disturbance

Question 39

What causes island patterns?

Answer 39

1. islands distant from source areas receive fewer colonizing species (distance effect)
2. larger islands tend to support more species (area effect)
3. species numbers increase on new islands and reach a stable # that is a balance between migration rate for species new to the island and the extinction rate for established species

Question 40

What causes mainland patterns ?

Answer 40

1. the number of species increases from the arctic regions to the tropics
2. diversity is favored in the tropics for 3 reasons
   - more rainfall and sunlight provides more food reserves
   - species diversity is self-reinforcing from herbivores to predators and parasites