chapter 37 part 2 Flashcards
energy…
flows
energy flows
energy from the sun can be stored in chemical bonds (photosynthesis) - used to do work and the rest is lost as heat
energy has to be continually added to the system
chemicals…
cycle
chemicals cycle
are recycled and used over and over again
biomass
the organic material in the ecosystem; living or was living (plant matter, animal bodies etc)
percentage of energy that moves up the food chain
10%
energy flow in ecosystems
only about 10% of the energy taken in by an organism is stored in its biomass (body) and can be used by the next level up for energy
“10 percent rule”
what percentage of the food we take in are used for life sustaining activity?
75%
when we eat plants…
we get our energy more efficiently than when we eat meat
land
used for growing grain and pasture land (much of the grain grown in the US is for animal food espcially corn and soy beans - 40% worldwide) (70% in the US)
predator
the consumer
have evolved mechanisms to help them catch an subdue prey (claws, teeth, fangs, stingers, poisons, etc; sharpened senses such as eyesight, smell and hearing)
prey
the food, including plants
most of animals energy and time are put toward
eating and avoiding being eaten
plants
have evolved many mechanisms to keep them from becoming food for insects and other herbivores (physical mechanisms, chemical defenses)
physical mechanisms for plants
spines and thorns; sap (sap will clog insects mouths as they try to eat tree, ex:rubber tree, chicle tree)
chemical defenses of plants
“defense compounds”
-poisons - to stop herbivores (ex: cyanide, struchnine)
-alkaloids (bitter taste) (morphine-opoium poppy, cocaine-cocoa, cannabis-marijuana, nicotine-tobacco, caffeine-coffee/tea)
some tropical plants have up to 90 different defense compouds
-heart stimulants (digitalin, milkweed)
-drugs to fight diseases (about 25% of prescription drugs come from plants vinblastine-leukemia, taxol-ovarian cancer)
-spices (bitter tasting) (cinnamon, cloves, pepermint
defense mechanisms for animals
- fleeing
- freezing
- potent scents (skunk)
- camouflage
- alarm calls
- mobbing
- quills (porcupine)
- chemical defenses
- mimicry
fleeing
(one of the most common defenses)
freezing
(movement help predators to “see” prey; predators will often overlook prey when they freeze)
potent scents
skunk
camouflage
(blend into the surroundings)
alarm calls
(to warn other members of the species)
mobbing
(to drive away predators; ex small birds may mob an hawk to get rid of hawk)
quills
porcupine
chemical defenses
(toxins; some species develop toxins; ex: monarch butterfly and poison frogs)
mimicry
(one species has evolved to look like another for protection; ex - monarch and viceroy butterflies
symbiotic
“living together”; interspecies interactions
- mutualism
- parasitism
mutualism
both partners benefit
ex: algae provides food for fungi- fungi provides habitat and water for algae
clownfish hides within the tentacles of anomones for protection- clowfish aerates anemones that get rid of parasites and lures other fish in for food
parasitism
one (the parasite) benefits at the expense of the other (the host)
ex: blood flukes on humans; ticks,tapeworms, leeches, any bacterial infection
disturbance
a force that alters the biological community and usually removes organisms from it
ex: fires, floods, volcanoes, glaciers, human intervention
- small disturbances create new habitats (tree falling over); large disturbances may take years for the community to recover (forest fire)
ecological succession
the process that an area goes through as it recovers from a disturbance; a series of predictable steps for recovery
primary succession
a community that arises from a virtually lifeless area, with no soil
ex: the rubble left by a glacier or the fresh lava flows of a volcano
-stage one: lichen begin to establish soil
stage two: mosses
stage three: weeds and herbs overgrow the mosses over time because they have the ability to grow vertically
stage four: grasses overgrow the weeds and herbs (in a grassland, this will be the final stage)
stage five: bushes and shrubs overgrow the grasses
stage six: small trees
stage seven: larger trees - called a climax community now
lichen
secrete enzymes that breaks up rocks; organic matter slowly forms as these plants die over many years
mosses
when a small amount of soil is produced, mosses can grow and slowly take over the lichen
secondary succes
when a community has been destroyed, but the soil is left intact; starts at stage three (herbs and weeds) and continues through stage 4 and 7; skips the soil recreation stages
ex: after a fire, drought, hurricane, agriculture
pioneer species
the first o become established; ex are weeds, herbs, etc; warrior species
warrior species
very protective of a recovering area (ex: poison invy, green brier, nature’s way of saying Keep out
fires
important role in ecosystems; return nutrients back to the soil, under natural conditions (grass lands burn ever 2-4 years; pine forests every 5-7 years
chemical cycling
- water cycle
- carbon
- nitrogen
water cycle
solar energy evaporates large amounts of water in seas (some falls back over seas and some fall back over land)
includes transpiration, surface water, and groundwater
transpiration
evaporation of water from plants (stomata open)
surface water
lakes streams and river
groundwater
water that seeps into the ground (acquifer)
carbon cycle
major ingredient of all organic molecules (carbohydrates, lipicds);
Nitrogen cycle
needed for proteins and nucleic acids, N in the atmosphere is not in a form that most plants can use; plants absorb nitrogran in their roots in several forms
