Transcript Chapter 3 “Biosphere”
Chapter 3 “Biosphere”
3-1 What is Ecology?
Ecology - study of how the living and nonliving world interacts.
Biosphere –
portions of the planet where all life exists (land, water, and air) Organisms and their environment
Biological Organization
Individual – a single organism of a species
Population –
group of individuals of the same species living together in a specific area
Biological Organization
Community – different populations living together in a specific area Ecosystem collection of all nonliving and living organisms living in a specific place
Biological Organization
Biome – group of ecosystems that have similar climates and communities
Biosphere -
portions of the planet where all life exists (land, water, and air)
Methods of study
Observation – using the 5 senses and recording our findings Experimentation testing the hypothesis; done in natural or unnatural (labs) environments Modeling – done when the event or object being studies is too large or too far from us.
Section 3-1 Assessment
1. List the six different levels of organization ecologists use to study the environment.
2. Describe the three basic methods of ecological research
3-2 Energy Flow
The main energy source for life on Earth is the sun. How do you and I use the sun’s energy?
Those organisms that directly use the sun’s light to produce their own food are called
Autotrophs.
Producers – another name for autotrophs on Earth
Energy Flow
Not all autotrophs use the sun’s energy. Some rely on other inorganic chemical compounds .
These are called
“chemoautotrophs”
Those organisms that do get their energy from the sun carry out a common process to use light energy to carry out chemical rxns.
Photosynthesis
Chemical rxn that converts carbon dioxide and water into oxygen and sugars
6CO 2 carbon dioxide + 6H 2 O C 6 H 12 O 6 water light energy sugar + 6O 2 oxygen
Chemosynthesis
Process used by some autotrophs, they use chemical energy to produce carbohydrates Similar to photosynthesis
Consumers
Cannot harness energy directly from the environment as autotrophs do, instead they acquire energy from other organisms.
Heterotrophs – organisms that rely on other organisms for their energy and food supply
Types of Consumers
Herbivores – obtain energy by eating only plants (cattle) Carnivores – obtain energy by eating other animals / meat (wolves) Omnivores – obtain energy by eating both plant and animals (humans)
Types of Consumers
Detritivores – feed on plant and animal remains and other dead matter (earthworms) Decomposers – break down organic matter (bacteria)
Levels of Consumers
Trophic Level: A step in a food chain or food web Primary Consumer: These individuals feed on producers; herbivores Secondary Consumer: These individuals feed on primary consumers; carnivores Tertiary: These individuals feed on secondary consumers; carnivores
Feeding Relationships
Energy flows through an ecosystem in one direction, it is not a cycle. It begins with the sun, then producers, and on to the consumers.
A diagram showing a single pathway of how energy travels through the ecosystem is called a food chain. A diagram showing multiple pathways of how energy travels through the ecosystem is called a food web.
Ecological Pyramids
Shows the relative amounts of matter in each trophic level in the food chain / web Energy Pyramid – only 10% of the energy stored in one trophic level is passed on to the next level; the remaining 90% is used or lost as heat.
Ecological Pyramids
Biomass Pyramid – shows the total amount of living tissue within a given trophic level; represents the amount of potential food available for each trophic level.
Numbers Pyramid – based on the number of individual organisms at each trophic level; shape is not always a pyramid
3-2 Section Review
1. What is the main form of energy that powers living things?
2. Briefly describe the flow of energy among organisms in an ecosystem.
3. What proportion of energy is transferred from one trophic level to the next?
3-3 Cycles
Unlike energy, matter is recycled within the ecosystem Biogeochemical cycles – show how elements, chemicals, and other forms of matter are passed from from one organism to another in the ecosystem.
Connects biological, geological, and chemical aspects of the biosphere
Water cycle
Evaporation – process by which water changes from liquid to gas form Condensation – process by which water changes from gas to liquid form Transpiration – process by water evaporates from the leaves of plants
Water cycle
When it rains, snows, etc. (precipitation) the water will… Runoff to ponds/lakes Soak in and become Groundwater Taken up by roots and transpire Evaporate
Carbon
Nutrient cycles
Nitrogen
Nutrient Limitation
Primary productivity
Limiting agent