Intro to Ecology Name: ________________________ NOTES#

Date: __________________ Period: _______

1. Ecology: the study of the interactions of living things with ______________________________a. Ecological Organization:

i. _____________________________: all the members of a species inhabiting a given location

ii. _______________________________: all the interacting populations in a given area

iii. _______________________________: the living community and the physical environment functioning together as an independent and relatively stable system

iv. __________________________: that portion of the earth where life exists, broken down into:

1. Lithosphere-

2. Hydrosphere-

3. Atmosphere-

b. Flashback: Can you remember the levels of organization smaller than population?

c. The biosphere is composed of numerous complex ecosystems.

i. An ecosystem involves interactions between ________________________ (physical) and

________________________ (living) factors.

1. The members of the community in the ecosystem and environment must interact to maintain a balance.

ii. An ecosystem is self-sustaining if the following requirements are met:

1. A constant _____________________________ and a living system capable of incorporating

this energy into organic molecules.

2. A _________________ of materials between organisms and their environment.

iii. In all environments, organisms with similar needs may ___________________ with each other for resources, including food, space, water, air, and shelter.

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2. Abiotic factors: those physical and chemical factors which affect the ability of organisms to

___________________________________________________________________________a. Some Abiotic Factors:

i. Intensity of ________________________________________

ii. Range of __________________________________________

iii. Amount of _________________________________________

iv. Type of _____________________________ (soil or rock type)

v. Availability of inorganic substances such as _______________________________________

vi. Supply of ______________________________ such as oxygen, carbon dioxide, and nitrogenvii. pH

** Each of the prior listed abiotic factors varies in the environment and, as such, may act as a

______________________________________, determining the types of organisms that

exist in that environment.

b. Some examples:

i. A _________________________________________ common to the northern latitudes determines in part the species of plants which can exist in that area.

ii. The __________________________________________________________ will help determine what species of fish live there.

iii. The dry environment of _______________________ limits the organisms that can live there.

c. Carrying Capacity - the ____________________________________________ the resources

of an area can support

i. The carrying capacity of the environment is limited by the available

______________________ and ___________________________ resources, as well as the

ability of ecosystems to _______________________________ the residue of dead organisms

through the activities of bacteria and fungi.

ii. Steady State- this occurs when the population remains relatively constant over a number of

years. This will occur when _____________________________________________________.

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3. Biotic factors: all the _______________________ things that directly or indirectly affect the environment.a. Thus, the organisms, their ____________________, ________________,

___________________, and _________________________ are all biotic factors.

4. Nutritional Relationships:

a. ________________________________: can synthesize their own food from inorganic

compounds and a usable energy source

b. ________________________________: can NOT synthesize their own food and are

dependent on other organisms for their food

i. Types of Heterotrophs: 1. Detritivore:

2. Herbivore:

3. Carnivore:

4. Omnivore:

ii. Types of Carnivores: 1. Predator:

2. Scavenger:

5. Symbiotic Relationships:

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a. Symbiosis: living together with ________________________________________ in close

association

b. Types of (symbiosis): mutualism, commensalism, parasitism

i. _____________________________: one organism is benefited and the other is unharmed 1. ex. barnacles on whales, orchids on tropical trees

ii. _____________________________: both organisms benefit from the association 1. Ex. nitrogen-fixing bacteria on legume nodules, certain protozoa

within termites (also ruminants)

iii. _____________________________: the parasite benefits at the expense of the host 1. Ex. athlete's foot fungus on humans, tapeworm and heartworm in dogs

6. Food Chains and Webs:a. If an ecosystem is to be self-sustaining it must contain a ____________________________

b. All life activities of living organisms require a constant source of ______________________

c. The pathways of energy through the living components of an ecosystem are represented by food chains and food webs.

d. Producers convert the ________________________ into the chemical energy of food.

i. _______________________: involves the transfer of energy from green plants through a series of organisms with repeated stages of eating and being eaten

ii. ___________________: In a natural community, the flow of energy and materials is much more complicated than illustrated by any one food chain.

iii. Since practically all organisms may be consumed by more than one species, many interactions occur along the food chains of any community.

e. Food Web interactions:

i. ______________________________: (plants) -- the energy of the community is derived from the organic compounds in plants (grass in the web above)

ii. ___________________________________: (always a herbivore) -- feeds on plants (mice, grasshoppers, and rabbits in the web above)

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iii. ____________________________________: (always a carnivore) -- feeds upon other consumers (frogs, sparrows, snakes, and foxes above) (The hawk is a secondary or 3rd level consumer depending on the availability of food.)

iv. Omnivores may be _____________________________________________________

v. Decomposers ____________________________________________________________

*** Through decomposition, chemical substances are returned to the environment where they can be used by other living organisms. ***

f. __________________________________ - Energy flows through ecosystems in one direction, typically from the Sun, through photosynthetic organisms, including green plants and algae, through herbivores, to carnivores, and finally decomposers.

g. There is a _________________________________________ in each level as you move up the food web. This means that there is much more energy in the producer level in a food web than at the consumer levels.

h. Energy Transfer - Each consumer level of the food pyramid utilizes approximately ________

of its ingested nutrients to build new tissue. This new tissue represents _____________ for

the next feeding level.

i. The remaining energy is lost in the form of _______________ and unavailable heat energy. Eventually, the energy in an ecosystem is lost and is radiated from the earth.

ii. An ecosystem cannot survive without the ___________________________ of energy from the sun.

i. __________________________: amount of organic matter

j. The amount of energy at each successive feeding level (trophic level) means that total biomass can be supported at each level.

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i. The total mass of carnivores in a particular ecosystem is __________ than the total mass of

the producers. (A pyramid of biomass illustrates this.)

7. Material Cycles:a. In a self- sustaining ecosystem,

_________________________________________ among the organisms and the abiotic environment. Thus the same materials can be reused. Materials constantly need to be recycled from the living and non-living environment so that materials can be reused by different living organisms.

b. Carbon Cycle - involves the processes of _______________________________ and

________________________.

i. Respiration:

ii. Photosynthesis:

iii. Each process compliments the other and the ecosystem maintains its balanced communities.1. Role of Plants:

2. Role of Animals:

3. Role of Dead Organisms

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To the left is a typical representation of a NY State terrestrial energy pyramid.

c. Nitrogen Cycle

1. Nitrates (used by plants)2. Build plant proteins3. Eaten by animals4. made into animal proteins5. Plants and animals die6. bacteria decay7. Ammonia (NH3)8. Nitrifying Bacteria9. Nitrates (used by plants)

d. Water Cycle: involves the processes of

8. Biodiversity:a. Evolutionary processes have resulted in a diversity of organisms and a diversity of roles in

ecosystems.

b. ______________________________ -- the differences in living things in an ecosystem

c. Increased biodiversity increases the _____________________ of an ecosystem.

d. Increased biodiversity increases the chance that at least some living things will survive in

the face of large changes in the environment.

e. ______________________________ -- planting one species over a huge area

f. Monoculture leaves an area more _________________________ to predation or disease.

i. Biodiversity ensures the availability of a rich variety of _______________ _______________ that may lead to future agricultural or medical discoveries with significant value to humans. (If this is lost we lose the sources of these materials for discovery)

ii. Biodiversity adds ____________________ qualities to the environment.

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9. Where Organisms Live:

a. Niches: ______________________________________

i. The organism's ______________________________________________, particularly its

role in relation to food with other species.

ii. Your niche is your job. For example you are a student

iii. It is the range of ________________________________________________________ in

which a species lives and the way the species obtains what it needs to survive and reproduce.

b. Habitati. ________________________________________, including the biotic and abiotic factors.

1. Examples:

c. Habitat vs. Niche:i. Woodpeckers make holes in this cactus to live. ii. When the woodpeckers are finished with this housing, the elf owl and the screech owl

move in. iii. The elf owl eats insects and the screech owl eats mice.

iv. Both occupy the same_______________________, but have different ________________.

10. Competitive Exclusion Principle:i. If two different species compete for the same food source or reproductive sites, one

species may be ________________. This establishes one species per niche in a community.

ii. If two species have the same niche, competition sets in resulting in:

1. __________________________ 2. __________________________

iii. Some species will divide resources with other species so they can share the same habitat.

b. ____________________________: occurs when two different species or organisms living in the same environment (habitat) utilize the same limited resources, such as food, water, space, light, oxygen, and minerals. i. The more similar the requirements of the organisms involved, the more intense the

competition. c. Keystone Species:

i. A species that is not usually abundant but exerts _____________________________on

the structure of the community.

ii. Usually the ______________________________________________________________

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