SYMBIOSISYour Subheading Here!

Definition

Symbiosis:A long-term, interactive

relationship between two different organisms.

Types

There are 3 types of symbiosis:commensalism,

mutualism,and

parasitism.

Commensalisman association between two

organisms in whichone benefits

andthe other is neitherhelped nor harmed

Mutualism

an association between two organisms in which

both benefit

Parasitism

an association between two organisms in which

one benefitsand

the other is harmed

What Type ?

Bees fly from flower to flower gathering nectar, which they make into food for their colonies. When they land in a flower,

the bees get some pollen on their hairy bodies, and when they land in the next flower, some of the pollen from the first one

rubs off, pollinating the plant, so it can reproduce.M

What Type ?

Spider crabs live in shallow areas of the ocean floor, and greenish-brown algae lives on the crabs‘ backs, making the crabs blend in with their environment and unnoticeable to

predators.M

What Type?

The Arctic fox follows caribou while they forage for grasses. The caribou dig in the snow to get the grasses. Once a caribou

digs up the soil, the Arctic fox comes and hunts some of the underground mammals that have come closer to the surface

due to the digging action of the caribou. C

What Type?

A certain kind of bacteria (bacteria = plural; bacterium = singular) live in the intestines of humans and other animals. A

human’s digestive system cannot digest all of the food a person eats. So, bacteria in the intestines eat the food that the

human cannot digest, and the bacteria partially digest it, allowing the human to finish the job.

M

What Type?

When horses, cows, and other livestock graze in fields, they tend to stir up and move many insects that have been resting

on the grass. The cattle egret then catches the insects and eats them. C

What Type?

Tapeworms are segmented flatworms that attach themselves to the insides of the intestines of animals such as cows, pigs,

and even humans. They get food by eating the host's partially digested food, depriving the host of nutrients. P

What Type?

Oxpecker birds perch on rhinos or zebras and eat ticks that live on their skin. The oxpeckers get food, and the beasts get pest

control. Also, when there is danger, the oxpeckers fly upward and scream a warning the rhinos and zebras have learned to trust. M

What Type?

Fleas find a host, such as dogs, and bite their skin, suck their blood, and cause them to itch. So, the fleas get food and a warm

home, and the hosts get itchy skin and sometimes infections. P

What Type?

Remora sharks have an adhesive disk on their dorsal (back) surface that allows them to attach themselves to whales or other

large marine animals. Once attached, the sharks feed on the remains, or uneaten scraps, from the other marine animal’s food. C

Review1. What are two key characteristics in defining

symbiosis?2. Who benefits in mutualism?3. What is commensalism?4. What is the 3rd type of symbiosis?5. Why isn’t there a type of symbiosis in which both

organisms are harmed?6. When a lion stalks a gazelle, catches it, and eats it, is

that a type of symbiosis? Why or why not?7. What type of symbiosis would best describe

a teacher-student relationship? Why?

Review ANSWERS1. What are two key characteristics in defining

symbiosis? long-term & interactive

2. Who benefits in mutualism? both benefit (it’s mutual!)

3. What is commensalism? In commensalism, one participant benefits, and the other is unharmed.

4. What is the 3rd type of symbiosis? parasitism

Review ANSWERS5. Why isn’t there a type of symbiosis in which both

organisms are harmed? All organisms learn from their mistakes, and they tend to avoid situations that might harm them.

6. A lion stalks a gazelle, catches it, and eats it. Does that scenario describe a symbiotic relationship? Why? No, this is an example of PREDATION. It is not a type of symbiosis because the relationship is a SHORT-TERM one, not a long-term one.

7. What type of symbiosis would best describe a teacher-student relationship? Why? Answers will vary, depending on perceptions!