Relationships between or-ganisms

Standard 4 Key Idea 6 PI 6.1 MU 6.1g

http://animals.about.com/od/evolution/ss/evolution_9.htm

http://science.howstuffworks.com/life/evolution/symbiosis.htm

Bell Ringer QuestionMosquitoes and humans

A mosquito bites a human and feeds on human blood.

Which organism benefits?Which organism is harmed?

The mosquito

The human

Today’s outline• Producer/ consumer• Predator/ prey• Symbiosis (parasitism, commensal-

ism, and mutualism)• Scavenger • Decomposer

Relationships between organisms may be negative, neutral, or positive. Examples

Negative: parasitismNeutral: commensalism Positive: mutualism

Producer/ consumer • Producer: use the sunlight to produceenergy (plants, algae)

• Consumer: use energyfrom producer. (usuallyanimals.) ; heterotroph

• Consumers eatproducers.

Predator/ prey • Predator kills and eats the prey.

http://www.sciencedaily.com/releases/2012/02/120222154633.htm

Symbiosis Symbiosis: a intimate relationship be-

tween two species that live closely.Examples1) Parasitism (+,-)2) Commensalism (+,0)3) Mutualism (+,+)

Parasitism (+,-)• One organism (the parasite) benefits.

(+)• The other organism (the host) is

harmed. (-) ExamplesAthletes’ food fungus (parasite)on humans (host)

http://www.health.com/health/gallery/0,,20307059_8,00.html

Parasitism (+,-) con’t• Examples con’tTapeworms (parasites) in humans and

pigsSigns: diarrhea, abdominal pain, and

weight loss.

http://www.humanillnesses.com/original/T-Ty/Tapeworm.html

Parasitism (+,-) con’t• Examples con’tHeartworms (parasites) in dogs (hosts)-The parasite infects the heart muscle of the

dog and kills it. -A mosquito carries the larvae of heart worms.

http://www.cesarsway.com/heartworm-awareness/Symptoms-of-Worms-in-Dogs

http://www.bucknerterraceanimal.com/Pages/Heartworms.aspx

Commensalism (+,0) • One organism is benefited. (+)• The other organism is neither

harmed nor benefited. (0)Examples-Barnacle-whale-Orchid-tree -Remora-shark

Commensalism example 1: orchids and trees

• The barnacle has access to food-rich waters.

• The whale is neither harmed nor benefited.

Commensalism example 2: orchids and trees

• The tree provides astable environment to orchids.• The tree is neitherharmed or benefited.

Commensalism example 3: remora and shark

• The remora eats food particles on the shark.The shark is neitherharmed or benefited.

Mutualism (+,+)• Both organisms benefit from each

other. • Examples-nitrogen fixing bacteria and roots of

plants (i.e. beans)-protozoa and termites-algae and fungi

Mutualism (+,+) example 1bacteria and roots of leguminous plants

-Bacteria obtain nutrientssuch as sugar from roots.-Roots obtain nitratesfrom bacteria.

Notes: leguminous plantsinclude beans, peas, andclover.

http://www.britannica.com/EBchecked/media/106760/The-roots-of-an-Austrian-winter-pea-plant-with-nodules

• The protozoa get nutrients in the termite’s intestine.

• The termite benefits because the protozoa digest wood.

Mutualism (+,+) example 2protozoa and termite

http://www.rikenresearch.riken.jp/eng/frontline/6132

Mutualism (+,+) example 3algae and fungi in a lichen

• Algae food to fungi• Fungi moist surface for algae

Video: Symbiosis: Mutualism, Commensalism, and Parasitism(Fill out the handout.)

http://www.youtube.com/watch?v=zSmL2F1t81Q

• Scavengers eat dead animals. (Some scavengers eat dead plants.)

Scavenger

• Decompose (break down) dead or-ganisms and return nutrients into the soil.

Decomposer

Exit ticket question 1• What are the three types of symbio-

sis you learned in class?

Exit ticket question 2

Regents June 2010 # 43