Biology

Cell Organelles and Features

Lesson Plan

Onion cells

State Standards:

High School Biology
2.1 Relate cell parts/organelles (plasma membrane, nuclear envelope, nucleus, nucleolus, cytoplasm, mitochondrion, endoplasmic reticulum, Golgi apparatus, lysosome, ribosome, vacuole, cell wall, chloroplast, cytoskeleton, centriole, cilium, flagellum, pseudopod) to their functions. Explain the role of cell membranes as a highly selective barrier (diffusion, osmosis, facilitated diffusion, active transport).

Listening and Speaking (S)
* S.1 Vocabulary: Students will comprehend and communicate orally, using English vocabulary for personal, social, and academic purposes. (FL 1, 2, 4, 5, 6, 7; ELA 4)
* Identifies important information on academic content using prior knowledge and/or visual cues as needed. (S.3.9)

Reading: Comprehension:Students will read English fluently and identify facts and evidence in order to interpret and analyze text. (ELA 8, 11)
* Formulates open-ended questions in order to explore a topic of interest. (R.6.7a)

Writing: Students will write in English for a variety of purposes with clear focus, coherent organization, and sufficient detail. (ELA 19; FL 1)


Essential Question:

Why membrane receptors transmit messages across the cell membrane?

Lesson Question:

How do membrane receptors transmit messages across the cell membrane?

Introduction:

Today we are going to discover how do membrane receptors transmit messages across the cell membrane.
In a biology lab some students are looking through a microscope at an unknown cell and they are confuse about the cell membrane and the cell wall. You want to help them. How you determine and explain whether it was a plant cell or and animal cell?

Task:

In a biology lab some students are looking through a microscope at an unknown cell and they are confuse about the cell membrane and the cell wall. How you determine and explain whether it was a plant cell or and animal cell?

To do this we will use a simulation, look through a microscope, and visit websites and video to determine what a cell membrane is. Then you create a Power Point presentation describing the structure of the cell membrane. Finally, you will quiz yourself and others. How can what you've learned help you teach another group of students?

Lesson Experiences:

1. Eliciting: Cells and Organelles

Discuss with a partner the answers to these two questions:

What is a cell?
What is an organelle?

Now let's figure out the boundaries of a cell.

2. Engagement: Activity about permeability

We know what a cell is, but what about its boundaries? Let's use a "physical metaphor" to find out.

Form a team of 4 or 5. You will take the balloons and scent given to you.
Using the dropper to put two or four drops of perfume or cologne into the balloons.
Then partially inflate each balloon and tie it off.
Then pass the balloons around.

Questions:
Are you able to smell the perfume or cologne?
How would the odor be able to pass through the balloon?

Discussion:
Discuss your answers to these questions with your group.

Now let's have you think about what separates cells from their environment but also may allow things to pass through, like the scent and the balloon.


3. Exploring: Activity with microscope

In almost every type of biological research, the microscope plays a fundamental role. Biologists use it to study the fine structures of cells and tissues, things that are too small to be seen with the unaided eye. The microscope used most often is the light microscope, which uses light to form an enlarged image of a specimen. A commonly used type of microscope is the compound light microscope. Compound light microscopes are used to view tiny living organisms as well as preserved cells mounted on glass (a microscope slide) and covered with a coverslip. This type of slide is prepared with water or some other liquid, such as a stain, and is called a wet mount.

In this lab, you will practice using a compound light microscope. You will learn how to make a wet-mount slide and will observe several cell structuresfrom Elodea and Onion.

In a group of four, prepare to use your compound light microscope. Work with the microscope and answer the following questions:

–As you look through the eyepiece, slowly adjust the diaphragm to obtain the appropriate light for viewing.
What happens as you adjust the diaphragm?

–As you look into the microscope, use your fingers to move the slide to the right and then to the left.

What happens to the image as you move the slide to the right?
What happens to the image as you move the slide to the left?

Then prepare a wet-mount slide to examine under the microscope.

Obtain a section of an onion. Make a wet mount of an onion layer, and observe it under high power. Observe one cell carefully for several minutes.

Identify the structures you see.
What movement do you see?

Observe one cell carefully for several minutes under high power.

Locate a vacuole. How many are there? What other cell structures do you see?

Obtain a leaf from the top of a sprig of Elodea. Make a wet mount of the leaf, and observe it under high power. Observe one cell carefully for several minutes.

Identify the structures you see.
What movement do you see?

4. Explain: Cells observed through the microscope

Respond to each other in your group about questions about the cells that you saw with the microscope. Complete the Cell Organelle worksheet. Then ask your instructor to doublecheck your answers.

5. Elaboration: View Cell Videos

Watch one of the videos or interactives listed below.

1) CellsAlive! Animation about cells
Cells Alive Plant Cell Simulation
click to visit website


Brightstorm video Eukaryotic Cells
Eukaryotic cell video still image
click to view video


Then create your own PowerPoint [or Glogster or Prezi] about the parts of the cells and the cell membrane in particular.

Make sure you answer these questions in the course of your presentation materials.

When your presentations are complete, share them with the class.

Conclusion:

You have completed lecture and laboratory about cell mambrane, Now you are able to explain how the cell membrane work and you can relate this process in the real world.

Assessments:

Finanally, let's see what you've learned. Go to Quizlet
and make flashcards for these terms:
• citoesqueletonúcleoretículoendoplasmático
• ribosoma aparato de Golgi vesícula
• mitocondriasvacuolalisosoma
• centriolo pared celularcloroplasto

Take the quiz for these flashcards "Cell Organelles"

Quizlet Flashcard on Cells
click to view flash cards


Share the results with your instructor.

Assessment Rubric
Category 4 Strong 3 Good 2 Adequate 1 Inadequate
Data & Results Data table and graph
neatly completed and
totally accurate.
Both accurate, some
ill-formed characters.
Both complete, minor
inaccuracies and/or
illegible characters.
Data table and/or
graph missing
information and are inaccurate.
Conclusion Presents a logical
explanation for
findings and addresses
most of the questions.
Presents a logical
explanation for findings
and addresses some
of the questions.
Presents an illogical
explanation for findings
and addresses few
questions.
Presents an illogical
explanation for findings
and does not address
any of the questions
suggested in the template.
Attractiveness Word processed or typed,
clean and neatly bound in a
report cover, illustrations
provided.
Legible writing, well-formed
characters, clean and neatly
bound in a report cover,
illustrations provided.
Legible writing, some
ill-formed letters, print
too small or too large,
papers stapled together.
Illegible writing,
loose pages.
Timeliness Report handed in on time. Up to two days late. Up to one week late. Report handed in
more than one week late.


Resources:

Materials:

Quizlet
http://quizlet.com/

DNA Tube: "Cell Biology"
http://www.dnatube.com/video/2318/Cell-Biology

DNA Tube "Tour of a Plant Cell" http://www.dnatube.com/video/1585/Tour-Of-A-Plant-Cell

TeacherTube "Real Housewives of Organelle County"

University of Illinois-- Biology video library
http://www.library.illinois.edu/biotech/teaching/video.html

Image Credit: Onion Cell