UTPA STEM/CBI Courses/Surface Area to Volume Ratio

Course Title: General Biology 2

Lecture Topic: Surface Area to Volume Ratio

Instructor: Matthew Terry

Institution: UTPA

Backwards Design
Course Objectives


 * Primary Objectives- By the next class period students will be able to:
 * Know what happens to surface area as volume increases
 * Be able to give real world biological examples of the consequences of this
 * Be aware of ways organisms get around this issue
 * Predict habitat of aquatic insects based on morphology


 * Sub Objectives- The objectives will require that students be able to:
 * Calculate surface area and volume
 * Think of examples from the biological world


 * Difficulties- Students may have difficulty:
 * Graphing


 * Real-World Contexts- There are many ways that students can use this material in the real-world, such as:
 * Determine if a structure functions as an organ for diffusion or temperature regulation based on morphology
 * Be able to explain how specific behaviors compensate for these principles

Model of Knowledge


 * Concept Map
 * What is surface area?
 * What is volume?
 * How are volume and surface area connected?
 * How does the shape of an animal affect these?
 * Real world examples (Emperor penguins, lungs, gills, small intestine, whales, etc.)
 * How are diffusion and heat conservation connected?


 * Content Priorities
 * Enduring Understanding
 * Surface Area to Volume ratio increase exponentially
 * This phenomenon affects the shape and behavior of organisms
 * Important to Do and Know
 * Calculate and graph surface area and volume for cube as it increases in size
 * Use EXCEL to observe the relations of this change
 * Demonstrate diffusion using agar and dye
 * Demonstrate cooling of water in different volumes and shapes
 * Worth Being Familiar with
 * How do insects compensate for this?
 * What organs are shaped to use this phenomenon?
 * Penguin example

Assessment of Learning


 * Formative Assessment
 * In Class (groups)
 * Compare measurements and graphs of different groups
 * Get examples of organs and/or organism behavior that demonstrate this principle
 * Place aquatic insects in their environment based on how they get their oxygen
 * Homework (individual)
 * Complete and turn in a lab report
 * Summative Assessment
 * Weekly Quiz
 * Final Exam

Legacy Cycle
OBJECTIVE

By the next class period, students will be able to: The objectives will require that students be able to: THE CHALLENGE
 * Know what happens to surface area as volume increases
 * Be able to give real world biological examples of the consequences of this
 * Know ways that organisms get around this issue
 * Predict habitat of aquatic insects based on morphology
 * Calculate volume and surface area
 * Use excel
 * Make logical predictions based on the learned concepts and observation

It's Not Easy Being Big: How does the relationship between surface area and volume impact living organisms?

GENERATE IDEAS

In class brainstorming and discussion

MULTIPLE PERSPECTIVES
 * Emperor Penguin example
 * Tissue pictures

RESEARCH & REVISE

Written and oral feedback from students

TEST YOUR METTLE
 * Open oral questions to the class
 * Written quiz at the beginning of the next lab

GO PUBLIC

Groups present their graphical results to the class

Pre-Lesson Quiz

 * 1) How do you calculate the volume of a cube?
 * 2) How do you calculate the surface area of a cube?
 * 3) What happens to the surface area of a cube as you increase its size (volume)?
 * 4) Does this occur at the same rate as you increase volume?
 * 5) Would this process change if you used a different shape, such as a sphere?
 * 6) What cools faster, 100 ml of water or 1000 ml of water?
 * 7) How might you slow the rate at which the water cools?
 * 8) Name an organ for which diffusion is a major part of its function.
 * 9) Name one strategy that organisms use to slow the amount of heat they lose.
 * 10) Why does a kangaroo lick its arms?

Test Your Mettle Quiz

 * 1) Which graph best represents the surface area to volume ratio of an elephant as it grows from a baby to an adult?
 * 2) What is the function of the alveoli in your lungs?
 * 3) How does asthma interfere with this function?
 * 4) Why are there no small marine mammals?
 * 5) Why are there small marine animals that are not mammals?
 * 6) What are three forms of insulation for arctic animals?
 * 7) How do emperor penguins survive the Antarctic winters?
 * 8) Gills in the diagram below are colored red. Which of the insects comes from an oxygen poor environment?
 * 9) Why are there no large insects?
 * 10) Describe the phenomenon of counter exchange and how it helps endotherms maintain their body temperature.