ECOLOGY PART 1 Levels Within Levels An ecosystem

ECOLOGY (PART 1)

Levels Within Levels • An ecosystem is a collection of all the organisms that live in a particular place, together with their nonliving, or physical, environment. Within an ecosystem, there are several levels of organization. Your school and its grounds are similar to an ecosystem. • 1. What living things are found in and around your school? • 2. What nonliving things are found in your school? • 3. Into what large groups are the students in your school divided? • 4. Into what smaller groups are these large groups divided? • 5. Are these groups ever divided into even smaller groups? If so, what are these groups?

WHAT IS ECOLOGY? • Study of interactions among 1. Organisms (Living-Living) 2. Organisms and their environment (Living-Nonliving)

SPECIES- A GROUP OF SIMILAR ORGANISMS THAT CAN BREED AND PRODUCE FERTILE OFFSPRING.

WHAT ARE THE SIMPLEST LEVELS? • Atom • Molecule • Organelle • Cell • Tissue • Organ • System 5

individual

3 -2 Ecological Levels of Organization Section 3 -1 Go to Section:

LEVELS OF ORGANIZATION • Individual- one organism (living) • Ex. a moose

LEVELS OF ORGANIZATION • Population(living-living same species in same area) • Ex. many moose

LEVELS OF ORGANIZATION • Community- groups of different populations (more than one population or different groups of species) Ex. many groups of moose beavers, trees, grass (all living)

LEVELS OF ORGANIZATION • Ecosystem- all organisms in a particular area along with the nonliving. (living and nonliving) Ex. many groups of moose beavers, trees, grass, rocks, water, mountains

LEVELS OF ORGANIZATION • Biome- group of ecosystems that have the same climate and similar dominant communities (same climate and communities) • Biomes: tropical rain forest, tropical dry forest, tropical savannah, temperate grassland, desert, temperate woodland shrubland, temperate forest, northwestern coniferous forest, boreal forest (taiga), tundra, mountains and ice caps

LEVELS OF ORGANIZATION • Biosphere- all of the planet where life exists, includes land, water, and, air • (EARTH) • Life extends 8 km up and 11 km below the surface

POPULATIONS, COMMUNITY & ECOSYSTEMS Organism Community Populations Ecosystem

CHECKPOINT • Would all the insects in a forest be considered a population? Why or why not? • No, there are many different species of insects this would be considered a community of insects.

WHAT SHAPES AN ECOSYSTEM? • Biotic factorsbiological (living) influences on ecosystem • Abiotic factorsnonliving influences on ecosystems • Ex. Interactions between organisms, predation, symbiosis, etc. • Ex. Temperature, precipitation, nutrient availability, soil type, sunlight.

ABIOTIC FACTORS • Nonliving parts of an ecosystem • Includes- water, sunlight, oxygen, temperature, and soil

BIOTIC FACTORS • Living parts of an ecosystem • Includes- grass, trees, people, animals, insects

NOW YOU DO: • Make a list of 5 biotic factors that can affect the environment • Make a list of 5 abiotic factors that can affect the environment. 19

HABITAT VS. NICHE • Habitat- an area where an organism lives • Niche- an organism’s way of life or its role in its environment including where in the food chain it is for example herbivores. • Habitat is like an address in an ecosystem and a niche is like an occupation in an ecosystem.

ENERGY FLOW (TROPHIC LEVELS) • Producers (autotrophs)- make their own food. • Get energy from the sun-by photosynthesis • Get energy without light- by chemosynthesis (chemicals) • Consumers (heterotrophs)- get energy from consuming producers and other organisms.

KEY POINT: TYPES OF HETEROTROPHS (FOLDABLE) • Herbivores- eats only plants • Carnivores- eats animals • Omnivores- eat both plants and animals • Detritivores (scavengers)- eat dead matter (plants and animals) • Decomposers- break down wastes and dead organisms and return nutrients to the soil/environment

FEEDING RELATIONSHIPS • Energy flows through an ecosystem in one direction from: • • 1. the sun or inorganic compounds 2. To autotrophs (producers) 3. To heterotrophs (consumers) Decomposers get energy from decomposing dead organisms

Food Chain- a series of steps in which organisms transfer energy by eating or being eaten. Food Web- A network of feeding relationships. (More realistic than a food chain)

TROPHIC LEVELS • Each step in a food chain or a food web is called a trophic level. • Producers are the first trophic level • Consumers are the second, third, or higher trophic level • Each trophic level depends on the one below for energy.

ENERGY PYRAMID • Only part of the energy stored in one level can be passed to the next- most energy is consumed for life processes (respiration, movement, etc. , and heat is given off) 10% • Only of the energy available within one trophic level is transferred to organisms in the next trophic level —the rest is given off as heat. • **Meaning that 90% is LOST as energy moves to the next trophic level.

PYRAMID OF BIOMASS • Biomass- the total amount of living tissue within a given trophic level. • A biomass pyramid represents the amount of potential food available for each trophic level in an ecosystem.

PYRAMID OF NUMBERS • A pyramid of numbers shows the relative number of individual organisms at each trophic level.

COMMUNITY INTERACTIONS • when organisms live together in an ecological community they interact constantly. • Three types of interactions • Competition • Predation • Symbiosis

COMPETITION- COMPETING FOR RESOURCES • occurs due to a limited number of resources • Resource- any necessity of life. water, nutrients, mates, space, shelter & food. • Competitive exclusion principle- no two species can occupy the same niche in the same habitat at the same time

PREDATION • Predation- when an organism captures and feeds on another organism. • Predator- hunter • Prey- hunted

SYMBIOSIS • Symbiosis- any relationship where two species live closely together. • (3 types) • Mutualism • Commensalism • Parasitism

SYMBIOSIS • Mutualism- both species benefit from a relationship. (+, +) • Examples: • Lichens (fungus and Algae) • Clownfish and Sea Anemone

SYMBIOSIS • Commensalism – One member of a symbiotic relationship benefits and the other is neither helped or harmed (+, 0) • Ex. Shark and Remora fish

SYMBIOSIS • Parasitism- One creature benefits and one creature is harmed (+, -) - Parasite harms the host • Ex. • tapeworm-Feeds in a humans intestines absorbing his/her nutrients. • Flea and dog

TICKET OUT THE DOOR 1. List in order the levels of organization starting with cells and ending with biosphere. 2. Compare the 3 types of symbiotic relationships and provide an example for each: Mutualism Commensalism Parasitism 37