intro to ecology chapter 18. cellular organization
DESCRIPTION
Levels of Ecological OrganizationTRANSCRIPT
Intro to Ecology
Chapter 18
Cellular Organization
Levels of Ecological Organization
Levels Smallest to largestCells Tissues Organs
Organ Systems Organism Population Community Ecosystem
Biosphere
Interdependence
Species interact with both other species and their nonliving environment
Levels of organizationPopulation- Includes members of a
single species that live in one place at one time.
Community- All the interacting organisms living in an area. Example: Fish, Turtles, plants, algae living in a pond together.
EcosystemEcosystem- includes all of the organisms and the nonliving aspects found in a particular place.
Example: Fish, Turtle, plants, water, sunlight.
The Biosphere
The broadest, most inclusive level of organization is the biosphere, the volume of Earth and its atmosphere that supports life.
Biotic vs. Abiotic FactorsBiotic- All living things that
affect an organism. (living components of the environment)
Abiotic- Nonliving factors.(physical and chemical characteristics of environment)
Examples are climate, water, sunlight, and pH.
BIOTIC OR ABIOTIC?? QUIZ:Tree? Oxygen?Cotton Shirt? Rain?Rabbit? Grass?Dead squirrel? Clouds?Owl Pellets? Bones?Steak? Leather?
Organisms in a changing environmentAcclimation
Some organisms can adjust their tolerance to abiotic factors through the process of acclimation
Organisms in a changing environment cont…
Conformers are organisms that do not regulate their internal conditions; they change as their external environment changes.
Regulators use energy to control some of their internal conditions. (homeostasis)
Organisms in a changing environment cont…Escape from Unsuitable ConditionsSome species survive
unfavorable environmental conditions by becoming dormant or by migrating.
Dormant Grass
Birds migrating
NicheAn organism’s niche is its way of
life or its role in its ecosystem.
Generalist-broad niches (oppossum)
Specialist- narrow niches. (koala)
Niche
ProducersMost producers are
photosynthetic and make carbohydrates by using energy from the sun.
AutotrophsExample: trees, plants, algae
Producers Cont…Gross primary productivity the rate producers in an ecosystem capture the energy of sunlight by producing organic compounds.
The rate biomass accumulates is called net primary productivity.
ConsumersConsumers obtain energy by
eating other organisms and include herbivores, omnivores, carnivores, detritivores, and decomposers.
Consumers are heterotrophs
Types of ConsumersHerbivore- eats only
producers (eats plants)Carnivore- eats only
consumers (eats animals)Omnivore- eats both
producers and consumers (eats animals and plants)
Detritivores- eats dead or decomposing material
Energy FlowFood Chains and Food Webs
A single pathway of energy transfer is a food chain.
A network showing all paths of energy transfer is a food web
Food Chain
Food Web
Energy TransferEcosystems contain only a few trophic levels because there is a low rate of energy transfer between each level
Energy TransferOn average 10% of energy is
transferred from one trophic level to the next.
The lower the tropic level the higher percent of energy available.
Energy TransferOrganisms at the lower levels are usually much more abundant than higher levels.
(1000 Zebras/ 1 Lion)
Water CycleKey processes in the water cycle
are evaporation, condensation, and precipitation.
Transpiration- the process of water evaporating from leaves of plants.
Water Cycle
Carbon CyclePhotosynthesis and cellular
respiration are the two main steps in the carbon cycle.
Burning fossil fuels releases carbon dioxide into the atmosphere.
Carbon Cycle
Nitrogen CycleNitrogen-fixing bacteria live in
soil and plant roots.This bacteria is important in the
nitrogen cycle because they change nitrogen gas into a usable form of nitrogen for plants.
The process of converting nitrogen gas to nitrate is called nitrogen fixation.
Recycling NitrogenDecomposers break down bodies of
dead organisms and urine to release the nitrogen they contain as ammonia, this process is known as ammonification.
The soil bacteria take the ammonia and then oxidize it into nitrates, this process is known as Nitrification.
Denitrifying bacteria then break down the nitrates and release the nitrogen to the atmosphere, this process in known at denitrification.
Nitrogen Cycle
Phosphorous CycleIn the phosphorus cycle,
phosphorus moves from phosphate deposited in rock, to the soil, plants absorb it through their roots, then passes to other living organisms, and finally to the ocean.