Tag Archives: respiration

One last revision note before the test…

Here’s the last part of revision for the test coming up at the end of this week. I’ve saved the Keynote from class as a PDF, which you can view and download below.

Photosynthesis and Respiration

Welcome back from the October break! I know you’re all excited to be back in class after a week of sleeping in and lazing around with your friends and families. Hopefully, the following lab experiment will ease everyone back into the routine of school…

The processes of photosynthesis and respiration are essentially inverse reactions. Photosynthesis uses carbon dioxide and water as reactants to produce glucose and oxygen gas. Respiration uses glucose and oxygen gas as reactants to produce carbon dioxide and water. The only difference is that photosynthesis requires an input of light energy to drive the reaction, energy which is stored in the C-H bonds of the glucose molecules produced.

Here you will find the instructions for Lab 31C Photosynthesis-Respiration (CO2 and O2), which I originally planned for the day we return from the break. Unfortunately, most of the science department order has not yet arrived, including our new oxygen sensors, which means we don’t have enough equipment for everyone to get to do the lab. But thanks to modern technology, we can still run the lab virtually! Open the document and read the questions and extensions after the procedure and data tables. These should help guide your thinking with the photosynthesis/respiration labs you’re designing on your own.

Photosynthesis-respiration lab setup. Screen capture image from Vernier Loggerpro.

Photosynthesis-respiration lab setup. Screen capture image from Vernier LoggerPro software.


The Carbon and Nitrogen Cycles

Biogeochemical cycles trace the movement of matter and nutrients through living organisms (“bio-“), planetary systems (“geo-“) and chemical reactions (“chemical”) throughout every part of Earth. The carbon cycle and the nitrogen cycle are possibly the 2 most important biogeochemical cycles on Earth. Here are a few fun videos to help you learn about these two essential cycles in our study of life and ecology.

First, a nice explanation of the carbon cycle:

Second, a little carbon music video:

Third, click on this link to BBC Bitesize Science for a very well-thought-out activity about the carbon cycle. It incorporates photosynthesis, respiration, biological molecules, and trophic levels.

Fourth, this animated tutorial found at W.H. Freeman thoroughly explains each step in the nitrogen cycle. While not super exciting, it’s well-done and includes a brief 3-question quiz.

Fifth, CrashCourse Science at YouTube offers us this entertaining and educational video about the nitrogen and phosphorus cycles (You don’t have to know about the phosphorus cycle in this class, but it’s helpful if you take more advanced biology courses):

Planning the Photosynthesis and Respiration Lab

I’ll add more later, but for the moment, please use this lab report planner to develop the investigation you will design into photosynthesis and respiration in Philodendron hastatum and Sansevieria trifasciata.

Below is a link to the planner as a Google form. When you complete the planner and click ‘submit,’ I will receive a digital version of your responses, which means I can then quickly see what you’re planning for your investigation and give you some timely feedback in class. ***Please note that you must be signed in to your IST Gmail account in order to see and use the planner form!

Click on the following link to download a MS Word version of the planner. It covers all parts of the lab report process in MYP science and is a little more detailed than the embedded Google form above. Photosynthesis-Respiration Lab Report Planner