Lesson # 2. How Organisms Interact

AUTHOR: Quratulain Hameed

 

DATE LESSON TO BE TAUGHT:  Unknown

 

GRADE LEVEL:  9th Grade

 

SOURCE:

Biology by Prentice Hall

Notes from Janice Lariviere

 

OBJECTIVES:

Students will be able to:

  1. Demonstrate energy flow through a food chain by constructing model food chain, and food webs.
  2. Distinguish different types of symbiotic relationships.
  3. Describe mutualism, parasitism and commensalisms.

 

TEKS:

1.a-1.c, 2.a-2.d, 9.c, 14.a,15.b

 

MATERIALS:

 Lichen, 20-25 slides, 10-15 microscopes, 10-15 prepared slides of nodule bacteria, construction paper, color pencils, 10 droppers, 20-25 cover slips.

 

ENGAGEMENT:

What the Teacher Will Do

Formative Assessment/ Evaluation

Student Responses

Have students list common pets. Ask students to identify the foods that are typically provided to each pet on their list. Ask the students to classify each pet as omnivore, carnivore, or herbivore based upon the foods it eats.

[This activity will show how much students know about these concepts, the teacher will be able to explain other concepts in detail if the students know these terms already]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

EXPLORATION: 

What the Teacher Will Do

Formative Assessment/ Evaluation

Student Responses

The purpose of todayÕs lesson is to look at the relationships organisms have with each other. In other words how organisms interact with other organism. The other concept we will explore today is by explaining the matter and energy relationships by ecological pyramids.

 

 

 

 

 

 

 

Many organisms live together, which is called symbiosis. We will perform an activity to further elaborate this concept.

Activity: what type of symbiosis is found in lichen?

1.     Take a bit of lichen that is provided by your teacher, and tease it apart with straight pins.

2.     Prepare a wet mount slide of the lichen pieces.

3.     Observe the lichen under the microscope.

 

 

 

 

 

 

 

 

 

1.     Describe the appearance of the two kinds of organisms that make up the lichen

2.     How could the alga or cyanobacterium benefit the fungus, and how could the fungus benefit the alga or cyanobacterium?

3.     What kind of symbiosis     

      exists between the  

      fungus and the alga or

      cyanobacterium?

 

 

 

 

 

 

 

 

The two organisms are attach to each other like parasite.

 

Algae is photosynthetic so it provide food for the fungus. Fungus helps algae to survive in habitat.

 

 

Mutualism.

EXPLANATION:

What the Teacher Will Do

Formative Assessment/ Evaluation

Student Responses

Symbiosis means living together. Organisms that live in same environment are in constant battle with other organism for their survival. Some interactions are beneficial for other organism while others are harmful. We classify these interactions as mutualism, commensalisms and parasitism.

Commensalism is a symbiotic relationship in which one species is neither harmed nor benefited.

 

 

Mutualism is a symbiotic relationship in which both species benefit.

Parasitism is a symbiotic relationship in which one organism derives benefit at the expense of the other.

 

 

 

 

 

 

 

 

 

 

 

Give some examples of           commensalisms.

                  

 

Give some examples of           mutualism.

 

Give some examples of           parasitism.

Distinguish between parasitism and predation.

A lion feeding on a deer. Is this parasitism or predation?

Based on the information given could you describe what kind of symbiosis exists between the fungus and the alga or cyanobacterium?

 

 

 

 

 

 

 

Spanish moss, orchids, & ferns drape themselves on branches of trees. The larger plants are not harmed but smaller plants benefit from the habitat.

 

 

 

 

 

 

Predation (wrong answer)

 

 

 

 

EXPLORATION:

What the Teacher Will Do

Formative Assessment/ Evaluation

Student Responses

Ask your students to take out a piece of paper and write down everything that they ate the last time they ate lunch. 

After 2 or 3 minutes, ask the students to name the things that they ate.  Put that list on the board or overhead, having them help you change the food items to the names of the plants and animals involved as you go – hamburger becomes wheat, cow, etc.

Ask the students to copy what you are writing on the board down on their own paper as you put it on the board.   When the students have a list of approximately 10 -15 items, have the students create as many food chains as possible – drawing arrows that show the way the energy is flowing.  Let the students figure out how to do this, accepting all attempts at this time.

When the chains are complete, ask the students to circle all the plants in their chains.

Can you name different things that you ate in dinner?

e.g. meat ball, pasta

What ingredients are involved with this type of food?

What does the pasta made off?

Where does the meatball come from?

 

Why do we need to know about food chains?

 

Cow, chicken, turkey, fish, tomato, lettuce, wheat, rice etc.

 

 

 

flour

 

cow

 

To find the flow of energy.

EXPLANATION:

What the Teacher Will Do

Formative Assessment/ Evaluation

Student Responses

 

 

 

Lead your students to describe producers and consumers and their roles in the flow of energy.  Have them link plants and animals to these terms.

Ask questions of your students which lead them to decide which way the arrows in the food chains could be drawn to actually represent the flow of energy.

Ask the students to think of terms that would describe consumers that eat producers versus consumers at eat lower order consumers.

You just drew a food chain. A food chain involves only one organism for each trophic level whereas a food web expresses all the possible feeding relationships at each trophic level in a community. A food web is a more natural model than a food chain since most organisms depend on more than one other species for food.

Where are the plants in your chains?  Why?

Where did the plants get their energy?

 

 

 

 

 

 

 

 

 

 

 

Do any of the food chains overlap?

If we combine these food chains, what do we have?

At the bottom. Because they are producers.

From sun.

 

 

 

 

 

 

 

 

 

 

 

 

 

Food Web

 

ELABORATION:

What the Teacher Will Do

Formative Assessment/ Evaluation

Student Responses

A symbiotic relationship exists between clover root nodules and bacteria. It is a mutualistic relationship commonly found in leguminous plants.

Activity: Have students observe prepared slides of nodule bacteria and make diagrams of their observations. Ask them to research the name of the bacterium that lives within the nodules. Students should write a report of their observations and explain how the relationship benefits both plant and bacterium and why it illustrates symbiosis.

[Making a food web: Have students design a food web using the following organisms: wheat, rat, fox, human, cow, corn, rabbit, hawk, grass. Ask them to use a colored pencil or marker to outline one single food chain. Ask them to indicate trophic levels as well as omnivores, hervivores, and carnivores.]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

EVALUATION:

I will be evaluating students throughout the lesson through formative assessment.