* Chapter 45 Flashcards
What is biodiversity?
The number of species that lives in that community
What is a habitat?
Aplace where an organism lives; it is characterized by distinctive physical features, vegetation, and the array of species living in it (biodiversity)
What is a community ?
it is an association of interacting populations of different species living in a particular habitat
What are the 5 factors that shape the structure of the community ?
- interactions between climate and topography dictate sunlight availability, rainfall, temperature, soil composition and so on
- availability of resources affects inhabitants
- adaptive traits enable individuals to exploit specific resources
- interactions of various kinds occur among the inhabitants; these include competition, predation, and mutualism
- physical disturbances (natural or man made), immigration, and episodes of extinction affect the habitat
What are tropics and artic enviornments? which one has a higher biodiversity and why?
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
The niche of each species is defined by…?
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
Interactions can occur between any __ species in a community and between entire communities
2
Describe and provide an example for a neutral relationship
hint: 0,0
- neither species directly affects the other (example: eagles and grass) both are members of the community however neither is disadvantaged or advantaged
Describe and provide an example for commensalism
hint: +,0
-One species benefits and the other is not affected (neutral). (Ex. Bird’s nest in a tree; the bird benefits but the tree neutral)
describe and provide an example for mutualism
hint: +,+
-There is a symbiotic relationship where both species benefit (Ex. the mitochondria, chloroplast and bacteria –> the theory of endosymbosis)
Describe and provide an example for interspecific compettion
hint: -,-
-When both species are harmed by the interaction (Ex. Whem embers of two different species fight and compete for resources)
Describe and provide an example for predation and parasitism
hint: +,-
-When one species (predator or parasite) benefits while the other (prey or host) is harmed
Define symbiosis
symbosis implies an intimate and rather permanent interdependence of the 2 species on one another for survival and reproduction
Which specie interactions are symbiotic
- commensalism
- parasitism
- mutualism
Define and provide examples for obligatory mutualism
- 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
What is the main difference between predators and parasites
- 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
_______ tends to favor parasite and host adaptions that promote some level of mutual tolerance and less-than-lethal effects
natural selection
Seldom rapid death results when a parasite attacks a host. It may happen if …?
the number of parasites overwhelm the host’s defenses
Parasites that live on the surface of the host are called..?
Ectoparasites. An example of this would be Lice
Parasites that live within the host’s body are called..?
Endoparasites. An example of this would be tape worms
What do microparasites include?
-bacteria, viruses, and protistans
What do macroparasites include?
-flatworms, nematodes, and small arthropods
What type plant parasites are Hemiparasites? give an example
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
What type plant parasites are Holoparasites? give an example
they are non-photosynthetic plant parasites.
Broomrape is an example. They need a host that produces glucose (food source) (light independent stage produces glucose)
What are social parasites and give an example.
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
Competition within a population of the same species is also called …?
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.
Interspecific competition is between …?
two different species. This type of competition is less intense because requirements are less similar between the competitors
(regardless of being inter- or intraspecific competition)
what is exploitation competition ?
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.
(regardless of being inter- or intraspecific competition)
What is interference competition?
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
allelopathy is the type of interference competition between ____
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).
what does competitive exclusion suggest?
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
when competitors’ niches do not overlap as much, the _____ is more probable
coexistence
differences in ______ will give certain species the competitive edge
adaptive traits
What is resource partitioning?
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
- what is ecological succession?
- Who are the pioneer species ?
- What is a climax community?
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.
What happens in primary succession?
-what do the pioneer species do?
- 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
Gradually other, usually _____, species join or replace the pioneer species
larger
In secondary succession a community _____ itself to a climax state after a ____
reestablishes; disturbance
What causes island patterns?
- islands distant from source areas receive fewer colonizing species (distance effect)
- larger islands tend to support more species (area effect)
- 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
What causes mainland patterns ?
- the number of species increases from the arctic regions to the tropics
- 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
