interactions of living things
DESCRIPTION
Interactions of Living Things. 7 th Grade Science. PART 1 . Biotic vs. Abiotic. -Biotic – all LIVING parts of environment. -ex: tree, fly, people -Abiotic – all NONLIVING parts of environment. -ex: water, soil, sunlight, temp . Levels of Environmental Organization. Organism - PowerPoint PPT PresentationTRANSCRIPT
Interactions of Living Things
7th Grade Science
PART 1
Biotic vs. Abiotic
-Biotic – all LIVING parts of environment.-ex: tree, fly, people
-Abiotic – all NONLIVING parts of environment.-ex: water, soil, sunlight, temp.
Levels of Environmental Organization
1. Organism2. Population – all same species that live in area3. Community – all species that live in area4. Ecosystem – community plus abiotic factors5. Biosphere – all ecosystems, anywhere life
exists
Salt Marsh – page 6
-What are some biotic factors in this marsh?*cordgrass *jellyfish*egret *heron*algae *marsh crab
-What are some abiotic factors?*water *sunlight*soil *temperature
PART 2
LIVING THINGS NEED ENERGY
Players in the Energy Game
-Producers – use sunlight to make food-ex: plants, algae
-Consumers – eat other organisms-herbivore – eats only plants-omnivore – eats both plants & animals-carnivore – eats only animals-scavenger – eats dead plants & animals
-Decomposers – get energy by breaking down dead organisms
-ex: bacteria & fungi-called nature’s recyclers
Food Chains
-Diagram that shows energy flow from one organism to another
-Why are these rare in nature?
Food Webs-More realistic than chains
-Interconnected chains show feeding relationships in ecosystem
-Arrows – is eaten by
Energy Pyramids
-diagram that shows loss of energy as it passes through food chains
Amount of energydecreasesas youmove upthe levels
Amount oftoxinsincreaseas youmove upthe levels
PART 3
TYPES OF INTERACTIONS
Limiting Factors
-Scarce resource that limits size population can grow
-ex: food becomes a limiting factor when population outgrows amount of
food available
Carrying Capacity
-Largest population an environment can support at any given time
-When a population grows larger than carrying capacity, limiting factors cause individuals to die or leave
Competition
-2 or more individuals or populations trying to use the same resource.
Predators vs. Prey
-Predator – organism that eats the prey-wide variety of methods & abilities for getting food
A cheetah’s speed gives it an advantage over other predators competing for the same prey
Prey Adaptations
-Prey have methods to keep from being eaten:1. stay in groups2. camouflage3. defense (poison, chemical, physical)4. burrowing
Stay in groups or Herds
Camouflage
22
Defense
23
Warning Coloration
24
Symbiosis
-Close, long-term association between members of 2 or more species
-classified as one of the following:1. mutualism2. commensalism3. parasitism
25
Mutualism
-Both organisms benefit from the interaction.-ex: you & e.coli in your stomach!!!
26
Commensalism
-One organism benefits, the other is unaffected.-ex: sharks & remoras
27
Parasitism
-One organism benefits, the other is harmed.-organism that benefits - parasite-organism harmed - host
-ex: Caterpillar & Wasp eggs