Date post: | 25-Dec-2015 |
Category: |
Documents |
Upload: | pierce-cecil-floyd |
View: | 222 times |
Download: | 1 times |
Objectives:
• Understand the elements that make up ecosystems and significance
• Make thorough observations of the elements of an ecosystem
• Make contributions to the construction of a food web
• Demonstrate comprehension of the interaction abiotic and biotic factors in ecosystems
Environmental InteractionsEcology- scientific study of the interactions between organisms and
their environment
Environment- surroundings
The environment consists of 2 parts:1. biotic factors- all living things that inhabit the environment
ex. Plants, bacteria, animals2. abiotic factors- nonliving parts of the environment
ex. Temperature, light, soil, air
Must have abiotic factors in order for biotic factors to exist
Limiting factors- factors that restrict the size of a population.ex. The amount of food, space
Organization of Life(simplest to largest)
1. organism- 1 living thing2. Population- group of organisms of the
same species living in the same area
-they compete for resources like food
3. community- all organisms living in the same
area (all populations in an area)-each population affects othersex. Fox affects rabbits
4. ecosystem- all living organisms plus their surroundings in an area2 general types of ecosystemsterrestrial- land ex. Forestaquatic-water
5. biosphere- highest level-all living and nonliving
parts of the earth-all living thingsare found here
How do organisms live in the same community without running out of resources?-they feed on different types of food-illustrated by food chain and food web
All organisms feed in 1 of 3 ways:1. producers- makes own food (ex. Plants)2. Consumers- ingest food from other organisms
(ex. Human)3. decomposer- breaks down organic matter to nutrients
(ex. Bacteria)
Types of feeding relationships in a community:
1. Autotroph (self-feed)- get energy from
the sun to make own food
2. heterotroph- organism that consumes
other organisms for food
types of heterotrophs:
a. herbivore- eats plants
b. carnivore- kills and eats animals
c. scavenger- feeds on animals already
dead (ex. Buzzard)
d. omnivore- feeds on plants and animals
ex. Human
3. decomposer- breakdown and absorb nutrients
from dead organisms (ex. Bacteria, fungi)
How is energy moved or cycled through the ecosystem?
By the food chain and food web
Food chain- model used to show how energy is moved from 1 organism to another
-shows one feeding relationship
ex. autotroph > heterotroph> carnivores
(arrow points to the animal that is doing that the energy is going to)
Each link on the food chain is called a trophic level
Food web• Shows multiple feeding relationships in an
ecosystem • It is the more reliable than the food chain
Each link in the food chain has 3-5 links only (no more). Why?
Energy is used at each link (each transfer)*Only 10% is passed on to the next level
Ex. Plant > grasshopper> fish> human
1000 cal 100 cal 10 cal 1 cal
energy pyramid- shows less energy transfer with each link of the food chain-organism number decreases with eachlevel
Components of an energy pyramid
Producers- always at the base/beginning of food chain
ex. Grass (bottom of pyramid)
Primary consumer- consumes plants directly man
ex. grasshopper fish
Secondary consumer- eats primary consumer grasshopper
ex. Fish plant
Tertiary consumer- eats secondary consumer
ex. man
Niche-role a species plays in its community (job)habitat-place where an organism lives out its life (ex. Aquatic habitat)
Questions for review:
• What is an ecosystem?• What elements make up an ecosystem?• How are the elements of an ecosystem related?• What is the relationship between producers and
consumers in an ecosystem?• How do organisms coexist in an ecosystem?• What is a food web?
Examples of organism interactions:
• Predation
• Competition
• Symbiotic relationships
Predation
• Predation-when one organism kills
anotherpredator- organism that kills
prey- organism killed
Each affects the size of the other’s population
competition• 2 organisms strive to obtain
the same limited resources (ex. Food)
• Both organisms are harmed somewhat
• Competition may be between the same species or between different
species
• “survival of the fittest”- the stronger of a species wins which weeds out the weaker ones
Close feeding relationships:Symbiosis-close feeding relationship in which one lives in or on another
organismTypes of symbiosis:
1. commensalism- relationship inwhich one organism benefits and the other is not affectedex. Moss on treeex. Cowbird on cow
2. mutualism- relationship in whichboth organisms benefitex. Bacteria in cowsex. Bee and flower
3. parasitism- relationship in whichone benefits and the other isharmedex. Tapeworm in stomachex. Mosquito sucking blood
Involves 4 processes:1. evaporation- changing from liquid to a gas (evaporation from
plants is called transpiration)2. condensation- changing from a gas to a liquid droplets (occurs in
clouds)3. precipitation- liquid returns to earth as rain, sleet, snow, hail4. respiration- water is breathed out from the lungs
Carbon cycleSource of carbon is Carbon dioxide in atmosphere
It is converted by plants to glucose by photosynthesis
Animals ingest the glucose and then die.
When they die carbon is returned to the air as carbon dioxide by bacteria when the matter decays.
student lab
home
Nitrogen cycle
• Nitrogen makes up 78%
of atmosphere.
• Problem: we cannot use it
unless it is converted to
nitrate.
• Only 2 things can convert
nitrogen to the form
we use.
These are:
lightning and
nitrogen fixing bacteria.
Do not copy—this is reviewExample of Food chains
Example of food web
Food web
• Everglade web
Consumer evolution host symbiosisDecomposer extinction limiting factor trophic levelDetritus food chain mutualismEcology food web omnivoreEcosystem habitat parasiteEnvironment herbivore predation