cell membrane

These Teacher Notes present key concepts and suggest learning activities that engage students in active learning and counteract some common student misconceptions. Students often think of a cell as a static structure consisting of multiple independent parts. They often do not understand how the parts of the cell work together to accomplish the multiple functions of a dynamic living cell. All of the suggested learning activities will help students to meet the Next Generation Science Standards (NGSS).

Section I presents key concepts and learning activities concerning cell structure and function, including differences between prokaryotic and eukaryotic cells and different types of eukaryotic cells. Section II presents key concepts and learning activities concerning the structure and function of cell membranes. The cell membrane is a particularly clear example of how the structure and function of a cell part can be understood in terms of the types and organization of its component molecules. The structure and function of mitochondria and chloroplasts are discussed further in the overview of cellular respiration and photosynthesis (https://serendipstudio.org/exchange/bioactivities#energy). Nucleus and ribosome function is discussed further in the overview of molecular biology (https://serendipstudio.org/exchange/bioactivities#molecbio).

The resources include:

In this hands-on, minds-on activity, students investigate the effects of hypotonic and hypertonic solutions on eggs that have had their shells removed. As students interpret their results, they develop a basic understanding of the process of osmosis. As they answer additional analysis and discussion questions, students learn about the effects of osmosis on animal and plant cells and apply their understanding of osmosis to the interpretation of several “real-world” phenomena.   

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Download Teacher Preparation Notes: PDF format or Word format

The Teacher Preparation Notes provide instructional suggestions and background information and explain how this activity is aligned with the Next Generation Science Standards.

This activity includes two hands-on experiments and numerous analysis and discussion questions to help students understand how the characteristics and organization of the molecules in the cell membrane result in the selective permeability of the cell membrane.

In the hands-on experiments, students first evaluate the selective permeability of a synthetic membrane and then observe how a layer of oil can be a barrier to diffusion of an aqueous solution.

Students answer analysis and discussion questions to learn how the phospholipid bilayer and membrane proteins play key roles in the cell membrane function of regulating what gets into and out of the cell. Topics covered include ions, polar and nonpolar molecules; simple diffusion through the phospholipid bilayer; facilitated diffusion through membrane proteins; and active transport by membrane proteins.

An optional additional page introduces exocytosis and endocytosis.