A level Biology Practice Questions - Help

Hello, I'm working my way through some practice Biology questions and I've come across one that has stumped me. I feel like maybe I'm just being a bit dense but could someone take a look at the question and walk me through how I'm supposed to work it out if you know how to do it please?

Question:
Scientists measured the rate of respiration in three parts of an ecosystem. They did this by measuring carbon dioxide released into the air by

• leaves of plants
• stems and roots of plants
• non-photosynthetic soil organisms.

The table below shows the scientists’ results for these three parts of the ecosystem.


Part of
ecosystem Mean rate of carbon dioxide production /

Leaves of
plants

Stems and
roots of plants

Non-
photosynthetic
soil organisms


(a) Complete the table to show the percentage of total carbon dioxide production by each part of the ecosystem. Show your working.

I know lots of sites give out an answer but I'd like to be able to actually understand it haha.

Starting with the leaves: we know that 0.032 cm3 m-2 s-1 is 25% of the total CO2 production measured.
Can you work out the value that would correspond to 100%?

Ah, I get it now lmao! Sorry it's super simple and I'm just being a muppet lmao thank you for being so helpful, I appreciate you taking the time to help.

Starting with the leaves: we know that 0.032 cm3 m-2 s-1 is 25% of the total CO2 production measured.
Can you work out the value that would correspond to 100%?

can u explain pls?

Which specific part(s)?

yes of course!! I am really stuck about how to work out what percentages the other values are (0.051 and 0.045) do you have to work out 1% i am so confused can you pls explain your working out to the question?

Using the values for the leaves (0.032 cm3 m-2 s-1 is 25% of the total), you can work out the total rate of production (i.e. 100%). Let's call this value n.

We therefore know that 0.032 ÷ n = 0.25.
Do the same for the other rates: 0.051 ÷ n, and 0.045 ÷ n.
And then multiply these values by 100 to get each percentage