Introducing Cells

Author(s): Linda Akiyama

Lesson Overview

Grade level(s):

Grade 3, Grade 4, Grade 5

Subjects(s):

Biology/Life Science

Topic:

Cells

Big ideas(s):

All living things are made of cells.

Vocabulary words:

Before: vocabulary from previous lessons in this unit.

During lesson - cell

What you need:

magiscopes with 10x eyepiece or microscopes(1 for each pair of students) , preprepared onion skin slides,  preprepared cheek cell slides(one of each for each pair of students), crystal violet to prepare cheek cells, paper and pencil for each child to sketch cells, CHARACTERISTICS OF LIVING THINGS WORD SEARCH

Magiscopes, microscopes, and all materials needed to prepare cell slides(except the onion) can be borrowed from UCSF SEP Library. There are also people there who can teach you how to use materials and make slides.

 

 

Grouping:

Pairs

Setting:

classroom

Time needed:

40 minutes

Author Name(s): 
Linda Akiyama
Summary: 

Students learn that all living things are made of cells. They use a microscope to look for evidence of plant cells(from onion) and animal cells(from human cheek).

This lesson is from the unit, "What is a Living Thing, and How Does a Living Thing Respond to Its Environment?" The unit is designed to supplement the adopted FOSS curriculum on life sciences. In this unit students are given time to think about and discuss the fundamental question, "What is a Living Thing?" They are also introduced to a process for planning science investigations on the topic of how different living things interact with their environment. The unit ends with students deciding on a testable question, designing an investigation, doing the investigation, collecting data and drawing conclusions. Students then create poster presentations of  their investigation for a grade level science fair.

Prerequisites for students: 

A prerequisite to teaching this lesson is to teach the previous lessons in this unit.

UNIT: What is Life and How Does a Living Thing Respond to Its Environment?

Lessons:

1) What Do Living Things Have in Common?

2) Living or Non-living?

Learning goals/objectives for students: 

Students will know that all living things are made of cells.

They will learn how to use a magiscope or microscope to observe cells.

They will be able to compare the differences between an animal cell and a plant cell structure.

Content background for instructor: 

A cell is the basic structural unit of a living thing.

Getting ready: 

Check out slide preparation material, magiscopes (or microscopes) from SEP. Someone at SEP will be happy to show you how to prepare cells. Prepare slides of onion cells and  slides of cheek cells.

Make one copy for each student of CHARACTERISTICS OF LIVING THINGS WORD SEARCH.

Lesson Implementation / Outline

Introduction: 

As whole class look at class list of the characteristics that all living things have in common. (See "What Do Living Things Have in Common?" lesson). If "made of cells" is not on the list, tell students that most scientists agree that all living things are made of cells. Explain that a cell is a very small basic unit of all living things. Cells are so small that a person needs to use a microscope to see them.  Today we are going to use microscopes to look at cells of an animal, and cells of a plant. We will draw these cells and then compare them.

Activity: 

1. Tell students that there may be times when their partners are looking and drawing the cells and they are waiting. Give them the CHARACTERISTICS OF LIVING THINGS wordsearch to work on while they are waiting (attached).

2. Tell students that they will be using a tool called a magiscope to observe cells.  It works very much like a microscope. Demonstrate how to use the magiscope . (Microscopes can be used as well.)Be sure to talk about not blocking the light source. Explain that they will first get a slide of a plant. It is a thin piece of onion. When both partners have looked at the onion skin and drawn what they saw, then they will get a slide of animal cells. It is a slide of cells from their teacher's inner cheek. Demonstrate how the cells were taken from the mouth.

3.  Hand out onion skin and demonstrate how to put them on the magiscope. Have students observe and draw. Circulate to help students focus magiscopes and to ask students to verbalize what they see. Do the same with cheek cells.

Checking for student understanding: 

Evaluate illustrations and students' oral responses during discussions. You may wish to have students write a reflection in their science journals about what they learned today in science.

Wrap-up / Closure: 

Have a class discussion about what students saw. List physical attributes of plant cells and animal cless and compare.

AttachmentSize
CHARACTERISTICS OF LIVING THINGS.doc27.5 KB

Standards - Grade 3

Life Sciences: 
3. Adaptations in physical structure or behavior may improve an organism's chance for survival. As a basis for understanding this concept:
a. Students know plants and animals have structures that serve different functions in growth, survival, and reproduction.
Investigation and Experimentation: 
5. Scientific progress is made by asking meaningful questions and conducting careful investigations. As a basis for understanding this concept and addressing the content in the other three strands, students should develop their own questions and perform investigations. Students will:
b. Differentiate evidence from opinion and know that scientists do not rely on claims or conclusions unless they are backed by observations that can be confirmed.
e. Collect data in an investigation and analyze those data to develop a logical conclusion.
»