How Do Hypotonic, Hypertonic, and Isotonic Solutions Affect the Water Movement of a Cell?
How Do Hypotonic, Hypertonic, and Isotonic Solutions Affect the Water Movement of a Cell?
Michael Halverson Valhalla High School El Cajon, California
Research Host: Kim E. Barrett, Ph.D. University of California, San Diego 1997 Grade Level: High School
How Do Hypotonic, Hypertonic, and Isotonic Solutions Affect the Water Movement of a Cell? Purpose: The purpose of this activity is to teach students about osmosis and the effects of hypotonic, hypertonic, and isotonic solutions on animal cells. This lab is designed for high school biology students but may be adapted for middle school students. Objectives: The students will be able to describe osmosis and differentiate between the effects of hypotonic, hypertonic, and isotonic solutions on animal cells and determine the equilibrium point for a chicken egg in corn syrup. They will also be able to apply this knowledge to human colonic (large intestine) epithelium, and the effects and consequences hypotonic, hypertonic, and isotonic solutions would have on these cells. Materials: This activity is designed for an entire class (from 20 to 36 students) working in pairs or trios, so that the class is divided into 11 groups. Each group (2-3 students) of students will need the following: • one raw egg • vinegar (approximately 5% acetic acid) • beaker or container • paper towels (or tissues) • balance • corn syrup • distilled water (tap water will work) • graduated cylinder • tape • pen • 0.5 cm graph paper Ask each group of students to bring in one egg. It is much less expensive to purchase the vinegar and corn syrup in large volumes, if possible. Stores that cater to restaurants and businesses or sell foods and products in quantity, such as Smart & Final, Costco, Price Club, etc., may offer lower prices. Also, ask to see the manager or ask the cashier if the establishment has an educator’s discount. All they can do is say no! If you live near a farm or egg ranch, ask the owner or manager if they will donate eggs to
Michael Halverson Valhalla High School El Cajon, California
Research Host: Kim E. Barrett, Ph.D. University of California, San Diego 1997 Grade Level: High School
How Do Hypotonic, Hypertonic, and Isotonic Solutions Affect the Water Movement of a Cell? Purpose: The purpose of this activity is to teach students about osmosis and the effects of hypotonic, hypertonic, and isotonic solutions on animal cells. This lab is designed for high school biology students but may be adapted for middle school students. Objectives: The students will be able to describe osmosis and differentiate between the effects of hypotonic, hypertonic, and isotonic solutions on animal cells and determine the equilibrium point for a chicken egg in corn syrup. They will also be able to apply this knowledge to human colonic (large intestine) epithelium, and the effects and consequences hypotonic, hypertonic, and isotonic solutions would have on these cells. Materials: This activity is designed for an entire class (from 20 to 36 students) working in pairs or trios, so that the class is divided into 11 groups. Each group (2-3 students) of students will need the following: • one raw egg • vinegar (approximately 5% acetic acid) • beaker or container • paper towels (or tissues) • balance • corn syrup • distilled water (tap water will work) • graduated cylinder • tape • pen • 0.5 cm graph paper Ask each group of students to bring in one egg. It is much less expensive to purchase the vinegar and corn syrup in large volumes, if possible. Stores that cater to restaurants and businesses or sell foods and products in quantity, such as Smart & Final, Costco, Price Club, etc., may offer lower prices. Also, ask to see the manager or ask the cashier if the establishment has an educator’s discount. All they can do is say no! If you live near a farm or egg ranch, ask the owner or manager if they will donate eggs to