UCSB Science Line
Sponge Spicules Nerve Cells Galaxy Abalone Shell Nickel Succinate X-ray Lens Lupine
UCSB Science Line
How it Works
Ask a Question
Search Topics
Our Scientists
Science Links
Contact Information
What does a plant do with the CO2 that is produced as a product of cellular respiration?
Question Date: 2018-08-26
Answer 1:

Good question. Plants sort of breathe through holes in their leaves called stomata. If they have more carbon dioxide than they can use immediately for photosynthesis, it just exits through the stomata.

The stomata are a problem for plants in dry climates because when they are open to allow carbon dioxide and oxygen to move into or out of the leaf, water also evaporates. When the plant gets dry, the cells that “guard the door” of the stomata shrink and they close. When there’s enough water, these cells swell up and open the stomata again.

Too much oxygen from photosynthesis can be a problem because if it builds up, it blocks the enzyme that should be grabbing onto carbon dioxide to complete photosynthesis. Some plants have special adaptations that allow them to avoid this problem. Check out C4 plants for more information. Some plants, like cacti, only open their stomata at night, when the air is cooler. This saves on water loss, but means they have less time to do gas exchange.

So there’s a whole complex balance of water, gas exchange, cellular respiration, and photosynthesis. Here’s another wrinkle, water evaporating through stomata is what pulls water up from the roots. If plants can’t pull water up, what else will they not be able to get?

Thanks for asking.

Answer 2:

During photosynthesis green plants manufacture the sugar molecules fructose and glucose. Green plants use energy from sunlight to build sugar molecules from carbon dioxide and water. ... During cellular respiration animal cells combine oxygen with food molecules to release energy to live and function.


Answer 3:

The plant releases the CO2 into the atmosphere, the same thing you do with CO2 that is produced as a product of cellular respiration. Generally, if a plant is respiring, then it's not photosynthesizing (usually this is because it's nighttime and so not enough light to photosynthesize), which means that it's an oxygen-breathing CO2-producing organism just like you are.

(Note to the above: many desert plants do their carbon fixation at night because it costs them less water to do so. These plants may use the CO2 from cellular respiration if they must).

Click Here to return to the search form.

University of California, Santa Barbara Materials Research Laboratory National Science Foundation
This program is co-sponsored by the National Science Foundation and UCSB School-University Partnerships
Copyright © 2017 The Regents of the University of California,
All Rights Reserved.
UCSB Terms of Use