Question

Mass of the organisms used in the videos:

Mass of the crickets: 48 g

Mass of the mouse: 16 g

Mass of the peas: 264 g

Mass of the rat: 129 g

Volume of the container: 32,000 mL (32 L)

Amal and Andraya, two biology students, have to develop a method to compare the respiration rates of different organisms.

Amal suggests making a graph of time and the carbon dioxide or oxygen levels of an organism to find respiration rate. Since the respiration rate is the amount of oxygen or carbon dioxide inhaled and exhaled per second, the slope of the graph will be equal to the respiration rate of the organisms and the units will be mL per second.

"But what about the different masses of different organisms?" Andraya asks.

Amal replies, "Because the respiration rates of four organisms are being compared, their different masses have to be accounted for. The size of an organism may affect the rate at which it metabolizes. We could look at respiration rate per gram which would give us a more accurate way to compare organisms of different masses."

Amal and Andraya conclude that in order to compare the respiration rate of an organism, they will use the slope of time(s) vs amount of carbon dioxide (mL) graph and divide by the mass of the organism to get respiration rate per gram. They could have used the oxygen amount but they decided to measure the amount of carbon dioxide instead.

1.Describe how you will calculate the respiration rates of different organisms when given the carbon dioxide levels, oxygen levels and a stopwatch. What are the units of the respiration rate?

2.What are two questions that you could answer?

Answer 1

I think , would also go by the same method , calculate the oxygen consumed or carbon dioxide exhaled (mL) in a minute ( not in seconds as i think they don't breathe every second so it will be difficult to recond ) a then divide it by the mass to exactly compare their rates per gram , which shall be uniform .

Unit could be mL/min/gram.

2. Two questions that I could answer by this, one is which of these respire the most or the least using the data of mL/min/gram. As this will give us per gram data , correct to have s comparison.

Second question which I could answer would be if mass of the organism is playing a role in the respiration rate. If the mass is higher, does the rate go down or low. Is it dependent or independent of that.