Grade 8 Science Lesson Plan

Topic: Cell Membrane: Permeability, Impermeably and Selective Permeability
Strand: Grade 8 – Understanding Life Systems: Cells
Time: 50 minutes

Expectations
Overall Expectations:
• Investigate functions and processes of plant and animal cells;
• Demonstrate an understanding of the basic structure and function of plant and animal cells and cell processes.

Specific Expectations
Developing Investigation and Communication Skills:
• Use scientific inquiry/experimentation skills to investigate the processes of diffusion and cells;
• Use appropriate science and technology vocabulary, including: diffusion, cell membrane, impermeable, permeable and selectively permeable in oral and written communication;
• Use a variety of forms (oral, written and graphic) to communicate with audiences and for a variety of purposes (draw and label permeable, impermeable and selectively permeable membranes as seen in the experiment).

Understanding basic Concepts:
• Explain the processes of membrane diffusion and its roles within a cell.

Resources: Science notebook, pencil, pencil crayons, Nelson Science and Technology 8
Experiment: jar, piece of glass, piece of mesh, piece of cloth, water, sugar, sugar-water solution.

Introductory Activity(15 minutes): Teacher will complete a mini-lesson about the membranes (permeable, impermeable, selectively permeable) in order to create oral awareness of the topic at hand. This main concept will be defined (a separating layer) and examples will be provided.

Developmental Strategies(30 minutes):
1) Now that students have gathered an awareness of the membranes a visual representation through experiment will take place;
2) The teacher will complete the experiment:
a) Place glass over water-filled jar and drop 1. sugar 2. sugar-water solution 3. water;
b) Place mesh over water-filled jar and drop 1. sugar 2. sugar-water solution 3. water;
c) Place cloth over water-filled jar and drop 1. sugar 2. sugar-water solution 3. water;
3) During the experiment students will have been drawing, labelling and describing the observations they made during the experiment for future reference;
4) The class will discuss, with teacher guidance, the relevance of the experiment to different types of membranes (some are permeable, impermeable and selectively permeable) and decide which type of membrane a cell has and why (selectively permeable because it allows some things to enter and keeps some out).

Concluding Activity: At their own desks students will answer the questions written on the board:

1) Explain what is meant by permeable, impermeable and selectively permeable membranes using examples from the experiment;
2) What type of membrane do cells have? Explain why.

They will be expected to use graphic and written tactics to explain the process.

Methods of Evaluation: Students will be evaluated based on their participation during class discussion. Their observations and answers to the questions in the concluding activity will also be collected and marked accordingly. These materials will show where each student stands in their understanding of the subjects.

Follow-Up Ideas: Students will use the knowledge gathered to continue their learning for the next subject: Osmosis.