1 of 10

The Arizona STEM Acceleration Project

Algae Culturing and Measurement of Gases:

Data Collection

2 of 10

Algae Culturing and Measurement of Gases:

Data Collection

A High School STEM lesson

Amber Struthers

12/10/2023

3 of 10

Notes for teachers

Context: This lesson takes place in a classroom in the context of three other lessons utilizing different STEM skills to support student understanding.

Students may work in small groups of 2-3.

Students are encouraged to utilizes a variety of approaches in support of additional concepts for collecting data.

Related Lessons

List of Materials

  • Spirogyra Culture (3 mL/group)
  • Graduated cylinder
  • Four 125 mL Erlenmeyer flask
  • 1 balloon
  • Light source, such as a lamp
  • Flask stopper with plastic tubing
  • Masking tape for labeling
  • Measuring tape

4 of 10

Arizona Science Standards

Essential HS.L2U1.21

Obtain, evaluate, and communicate data showing the relationship of photosynthesis and cellular respiration;

flow of energy and cycling of matter.

Plus HS+B.L2U1.8

Develop and use models to develop a scientific

explanation that illustrates how

photosynthesis transforms light energy into

stored chemical energy and how cellular

respiration breaks down macromolecules for

use in metabolic processes.

Science and Engineering Practice

  • Ask questions to determine relationships, including quantitative relationships, between independent and dependent variables.
  • Apply scientific knowledge and evidence to explain phenomena and solve design problems, taking into account possible unanticipated effects.
  • Use tools, technologies, and/or models (e.g., computational,mathematical) to generate and analyze data in order to make valid and reliable scientific claims or determine an optimal design solution.

5 of 10

Objective(s):

Students will explore the process of photosynthesis to examine the products of the process.

Students will reflect the benefits and challenges of utilizing algae to solve real-world problems.

Students will examine the byproducts of photosynthesis, collect and analyze data, and develop an argument about how effective algae can be to solve a real-world problem.

Students will utilizes their generated data from the lab and develop graphs to support their argument.

6 of 10

Agenda (60 minutes)

Phenomena: What kind of data can be collected from observing photosynthesis?

Hands-On Activity: Data Collection

Reflection and prediction

Resources:

7 of 10

Hands-on Activity Instructions

Day 3 Procedures: Data Collection

1) Record any observations in the data table, color, bubbles, smells, etc.

2) Use a piece of string to measure the circumference of each balloon in cm. If the balloon does not look noticeably different from the start of the experiment, calculate the circumference of the balloon as zero. Record in data table using significant figures rules

3) Read the level of the air in the gas collection tube (graduated cylinder) from flask #4 and record in the data table after converting to cm3 using dimensional analysis.

8 of 10

Hands-on Activity Instructions (cont.)

4) Use the circumference of the balloon and the following equations to calculate the radius (r) of each balloon. Record in data table using significant figures rules C = 2πr

5) Calculate the volume of gas produced in flasks using the following equation. Record in data table using significant figures rules

Volume of Gas Produced = 4/3π × (radius of balloon in cm)3

6) Clean up your lab supplies. Make sure to wash out all flasks thoroughly.

9 of 10

Assessment

Formative Assessment: Student discussion and reflection:

What gases would be produced in this process? How do you know - what observation was seen to show this production?

Which flask or flasks had no observable gas production? Why is this so?

Which flask(s) produced the largest volume of gas? Why might this be so?

Summative assessment:

Proper data collection, calculation of circumference, diameters, and volume as appropriate.

10 of 10

Differentiation

A possible remediation support can be examination of photosynthesis utilizing virtual lab resources such as those available on BioMan or Gizmos.

Students can utilize digital resources to support their understanding of the process of photosynthesis and examine how these process could utilized to solve real-world problems.

Remediation

Extension/Enrichment

Students can utilize similar experimental set ups and introduce additional variables to see if they influence the process of photosynthesis. This would be an opportunity to examine products that claim to impact plant growth and examine if they actually influence the process of photosynthesis.

Students can examine how algae are being utilized to address challenges such as plastic and fuel production as well as improvements to resources such as water and air.