get energy from sun or chemical sources and use inorganic compounds
feed on primary producers that use sun for energy
feed on herbivores and other heterotrophic organisms
way of ID what kind of food an organism uses
in food chains, the total TL depend on location and number of different species.
in gen. highest TL occupied by adult animal with no predators of their own: Killer Whale in Antarctic food chain
primary source of energy!
-Autotrophs/primary trophic levels w/ the greatest biomass
-Plants absorb sunlight and convert it to chem. energy (glucose) via photosynthesis
- second trophic level w/ less biomass than producers
- eats plants and derive energy from glucose
- these consumers have large energy losses from metabolism so only a small amt. of energy is transferred to the next level.
-third trophic level w/ small biomass
-similar to primary consumers only a small amt. of energy is transferred (energy loss)
scavengers (vultures)/ decomposers (fungi and bacteria). This group lives on dead organic matter and consume organic matter derived from many trophic levels.
eats both plants and animals
Primary consumer: insects
Secondary consumer : spiders
Tertiary consumer: birds
Final consumer: hawk
In a food chain, energy moves in a _______ fashion from __________ through _________.
How is energy captured by? and what is it transfer to?
How much energy is passed on?
Energy is captured by primary producers and transferred to higher trophic levels.
At each transfer, only a fraction of the energy is passed on and much is lost.These losses appear in the form of heat and in inefficiencies in processing and assimilating energy.
The total available energy _____ as one moves up trophic levels in a food chain.
What does this do to the number of trophic levels?
This places a limit on the number of trophic levels that can exist. At some point, there's too little energy available to sustain further transfers.
The food chain can be expanded into the food web which is more accurately depicts what happens in real life.
1) Plants --> 2) Rats/mice, insects, ducks
3) Small birds
Is Nitrogen one of the most abundant elements on Earth?
What percentage of Earth's atmosphere is N in gas form?
Can living cell exist without N?
No, no living cell can exist without nitrogen.
Can organisms use N in gas form?
Organisms cannot use N in gas form
How do multicellular life (plants, animals, and fungi) obtain nitrogen?
Multicellular life depend almost entirely on bacteria to obtain (or "fix") N from the air and transform it into a chemical form that plants can use.
Where are some places you can find the bacteria that fixes atmospheric N?
-some live symbiotically w/ legumes (like beans) which take N out of the air in soils.
-some live freely in solid, processing manures and urine, and also help decompose dead plants and animals.
- in ocean, cyanobacteria fix N for marine life
How do plants get N?
Plants assimilate N from soil and with it create a.a. and proteins
How do animals get N from?
Animals get N from eating plants or from eating other animals.
What are the the two major beginnings and two major paths in the N Cycle?
Nitrogen from air -> soil -> N-fixing bact. -> Nitrifying bact.-> plants -> animals -> decomposers
N from dead organism -> decomposers -> nitrifying bact. ->plants
Little N is fixed by lightning and volcanoes release some N which both are carried to soils by rain!
Is life on Earth carbon-based (C-based)?
True or False. Carbon is not a lively element that does not readily combine with other elements to make organic compounds.
False. Carbon is a lively element that not readily combine with other elements to make organic compounds.
Is a relatively large % of our body made up of carbon?
How do animals obtain C?
Through photosynthesis, plants make carbohydrates (chemical compounds made of C, O, and H) that animals then eat for food.
How do humans accumulate C?
from plants directly or indirectly by eating plants or the animals that consumed plants
Area all components of the Carbon Cycle very fast?
Some components of the C cycle are very fast; however, the rock-forming part and the coal-petroleum-natural gas part take millions of years
What are the largest reservoirs of carbon in the ocean? Is this source of C accessible to life?
Sediments; however, this source of carbon is not accessible to life.
What are the largest reservoirs of carbon and what % does it comprise of of the aboveground/on land carbon? Where is most of it?
forests; 80% of the aboveground carbon; most of it is in the tissues of trees.
____ and the _________ together hold about ____% of the world's forest carbon.
Are living organisms are crucial to the carbon cycle?
Russian and the Amazon basin; 45%
an indiv. form of life, (plant, animal, bacterium, protist, or fungus) a body made up of organs, organelles, or other parts that work together to carry on the various processes of life.
all the organisms that constitute a specific group, found in a specified habitat and that can interbreed.
A group of plants and animals living and interacting w/ one another in a specific region under relatively similar environmental conditions. The region occupied by a group of interacting organisms. It is a biotic community meaning living organisms only.
Involves the interaction of living (biotic) communities and the non-living (abiotic) factors in their environment (biomes).
the biosphere is the part of the earth and its atmosphere in which living organisms have the potential to exist. The biosphere is comprised of the living org. and their surrounding environment---the biosphere may be though of as a conglomeration of all the portions of the planet that support life: the atmosphere, lithosphere, and hydrosphere.
The envelope of gases surrounding the earth or another planet
The crust and upper mantle of the earth
All the waters on the earth's surface, such as lakes and seas, and sometimes including water over the earth's surface, such as clouds.
a rounded spherical form.
What are the two patterns of population growth?
Logistic population growth and exponential growth
What is Logistic population grow?
-S-shaped curved or sigmoidal
-occurs more often in nature;
- K is the carrying capacity; the environment can only support a certain number of living things b/c of limited resources (water, food)
What is Exponential populations growth?
There are no limiting factors (unlimited resources)
Characteristic of bacteria in a lab provided with all nutrients and ample (plenty of) space to grow
typically not the growth pattern followed by nature.
an association btwn organisms of two diff species in which each member benefits.
tick bird and rhino
legumes and nitrogen fixing bacteria
E.coli and humans
-A symbiotic (living together but not necessarily beneficial) btwn. two organisms of diff. species in which on derives some benefit while the other is unaffected.
- example: Barnacle lives on a whale but the whale is unaffected
The relationship between two organisms in which one org. benefits from the other at the other's expense. The damage incurred by the other organism, however, is usually not fatal.
tapeworm and human
-All animals must eat to survive. With predators always on the look out for a meal, prey must constantly avoid being eaten.
-Any adaptation the prey uses adds to its chances of survival for the species. Some adaptations are defense mechanisms which can give the prey and advantage against enemies.
What is succession?
The gradual and orderly process of ecosystem development brought about by changes in community composition and the production of a climax characteristic of a particular geographic region is known as a succession.
What is primary succession?
occurs where no previous organisms existed. An example would be a new island that formed as a result of a volcanic activity.
What is a secondary succession?
Occurs where the existing community is removed (fire)
Changes occur because each community that established itself changes the environment, making it more unfavorable for itself and more favorable for the community that is to succeed it.
Example of Succession:
Barren rock surface (never before colonized)--> Lichens and mosses (pioneer community) able to survive in hard conditions -> Annual grasses -> perennial grasses -> shrubs
How many categories can biomes be classified into and what are they?
Lichens, mosses, sedges, perennial forbs, dwarfed shrubs (often heaths, but also birches and willows)
What are the growth forms found in tundras?
Growforms: typical are ground-hugging and other warmth-preserving forms including: rosettes and dwarf shrubs
What is the climate in tundras?
- extremely short growing season (6-10 wks)
- long, cold, dark winter (6-10 months w/ mean monthly temp. below 32 degree F or 0 degree C)
- low precipitation (less than five inches/year) coupled with strong, drying winds. Snowfall is actually advantageous to plant and animal life as it provides an insulating layer on the ground surface.
What are the three adaptations found in wildlife tundras?
among small number of bird (ptarmigan) and mammal (muskox, arctic hare, arctic fox, musk ox) species that reside year-round on the tundra on commonly finds:
Morphological adaptations, physiological adaptations, population adaptation
What are morphological adaptations are advantageous in tundras?
-large, compact bodies;
-a thick insulating cover of feathers or fur;
-pelage and plumage that turns white in winter and brown in the summer.
what are physiological adaptations are advantageous in tundras?
-abiligy to accumulate thick deposits of fat during the short growing season
- fat acts as insulation and as a store of energy for use during the winter, when animal species remain active.
what are population adaptations are advantageous in tundras?
cyclical fluctuations in population size; best seen perhaps in the lemming, a small rodent which is the major herbivore in the tundra's simple food chain.
-predator population and plant pop. respond in kind to the peaks and crashes of the herbivore population.
Migratory species such as the waterfowl, shorebirds, and caribou adapt to the tundra by avoiding the most severe conditions of winter. How?
Each year at the end of the short growing season, they move southward into the boreal forest or beyond, but return to the tundra to breed.
Give an example of aperiodic emigration in the tundra.
Snowy owl; during those years that the lemming pop have crashed, winters see snowy owl irruptions (sudden appearance) as far south as Virginia
- most owls found w/ empty stomach & don't survive to return to the Arctic
What is the distribution in the tundra biome like?
Restricted to the high latitudes of the N. hemisphere in a belt around the Arctic Ocean. Many of its species, both plant and animal, have circumpolar distribution areas (meaning surrounding the earth's poles and about the equator)
What is a Taiga?
also known as boreal forest- exists as a nearly continuous belt of coniferous (cones and evergreen leaves) trees across N. Amer. and Eurasia.
-mosaic (combo of) successional and subclimax plant communities sensitive to varying environmental conditions.
-Russian name for this forest which covers so much of that country and also used in N. Amer.
What is the climate in taiga?
-corresponds w/ regions of subartic and cold continental climate
-long, severe winters (up to six months w/ mean temp below freezing) and short summers (50 - 100 frost free days)
- wide range of temp btwn winter and summer- Russia: -90 dF and +90 dF
-Mean precip. 15-20 inch, but low evap rates make this a humid climate
What is the vegetation like in taiga?
-needleleaf, conferous trees are the dominant plants
-four main genera: evergreen spruce, fir, and pine, and deciduous larch or tamarack.
-in N. Amer. 1 or 2 species of fir and 1 or 2 of spruce are dominant
- Scandanavia + W. Russia, the Scots pin common
-Broadleaf deciduous trees and shrubs are members of early successional stages of both primary and secondary such. (alder, birch, aspen)
What are the growthforms in Taiga?
The conical or spire-shaped needleleaf trees commons to the taiga are adapted to the cold and the physiological drought of winter and to the short-growing season:
conical shape, needleleaf, evergreen habit, dark color
What is the benefits of conical shapes in a taiga?
promotes shedding of snow and prevents loss of branches.
What are the benefits of needleleaf in a Taiga?
narrowness reduces surface area through which water may be lost (transpired), especially during winter when the frozen ground prevents plants from replenishing their water supply.
what are the benefits of evergreen habit in a taiga?
Retention foliage allows plants to photosynthesize as soon as temperatures permit in spring, rather than having to waste time in the short growing season merely growing leaves.
what are the benefits of dark color in a taiga?
The dark green of spruce and fir needles helps the foliage absorb maximum heat from the sun and begin photosynthesis as early as possible.
What is the Tropical Rain Forest?
-earth's most complex biome in terms of structure and species diversity
-occurs under optimal growing conditions: abundant precipitation and year round warmth.
-no annual rhythm to the forest; each species evolved own flower and fruiting seasons.
-sunlight is a major limiting factor
- a variety of strategies have been successful in the struggle to reach light or to adapt to the low intensity of light beneath the canopy.
what is the climate of trop. rain forest?
-mean monthly temp 64 dF, precip over 100 inches/yr
-usually brief season reduced precip.
-in monsoonal areas, there is a real dry season, but that is more than compensated for w/ abundant precipitation the rest of the year.
What is the wildlife like in the trop. rain forest?
great variety of plants and animals;
Tropical species of trees frequently possess one or more of the following attributes not seen in trees of higher latitudes. What are they?
Buttresses: many species have broad, woody flanges at the base of the trunk. Originally it was believed that their role was to support the tree; now it is believed that the buttresses channel the stem flow and its dissolved nutrients to the roots.
Large leaves: the L leaves surface helps intercept light in the sun-dappled lower strata of the forest
Drip tips: facilitate drainage of precipitation off the leaf to promote transpiration
What are desert?
-rarely devoid (entirely lacking) of life. Instead they abound w/ wonderfully adapted plants and animals that have evolved various mechanisms for tolerating or avoiding the extremes of aridity(fruitlessness) and temp that might be encountered in biome.
What is the climate of a desert?
-arid climates that average less precip. 10 inch/yr
- potent evap exceeds precip., rainfall is highly localized and relatively unpredictable in terms of when it will occur, although usually there are seasons of highest probability for rain.
-precip and temp changes, may exceed 100 dF on summer, but dip 20-30 or more at night
-winters cool to cold,"hot deserts" rarely frost
"cold" deserts have prolonged periods of below freezing temp and snowfall
What is the vegetation like for deserts?
-shrubs are the dom. growth form of deserts
- may be evergreen or deciduous- typ. sm. leaves and frequently have spines or throne or/and aromatic oils. shallow but extensive root systems procure rainwater from well beyond the canopy of the shrub whoever it does rain.
water is not entirely lacking in the desert envier. and sev. other growth forms rep. strategies to reach water or to store water.
What is the wildlife in deserts?
-reptiles w/ waterproof skin, production of uric acid instead of urine, hard-shelled eggs, and ability to gain body heat directly from the sun and to retreat to shade or underground to avoid heat are exceptionally well adapted to drylands.
-most animals are nocturnal (active at night) when the temperature is lower.
what are deciduous/ temperate forests?
Found esp. in N. Amer. and is known for turning of the colors of its leaves to brilliant reds, oranges, and golds in autumn.
-The shortening days of fall stimulate the plants to withdraw chlorophyll from their leaves, allowing a brief but beautiful display of other pigments before the leaves are shed completely and plants ever an extended period of dormancy
what is the climate like in deciduous/temperate forests?
assc. w/ warmer continental and humid subtropical climates. Aprox. 6 mon growing season. 20-60 inches of rain even distrib. through yr. non-growing = cold, temp-induced drought winters
what is the vegetation in decid/temp forests?
same genera, oak, maple, beech, chestnut, hickory, elm, tilia/basswood, walnut, sweet gum. diff species of these genera occur on each continent.
what is the wildlife in the deciduous/temperate forests?
either mast-eaters (nut and acorn feeders) or omnivores (eats both plants and animals)
-mammals show adaption to an arboreal life; a few hibernate during the winter months.
- N. Amer. herbivores : white-tall deer, gray squirrel, chipmunk
-omnivores: raccoon, opossum, skunk, and black bear
-carnivores have been largely eliminated through the deliberate effort of humans but should include timber wolves, mountain lions, and bobcats. The coyote, native to the western grassland and deserts have recently dispersed east and taken over the niche of its departed cousin, the timber wolf.
-resident bird tend to be seed eaters or omnivores.