2.8 IB Respirometers

What is the purpose of the soda lime in this lab?

• absorbs oxygen

• absorbs carbon dioxide

• facilitates respiration

• keeps the temperature regulated

Answer explanation

Soda lime is a base and absorbs CO₂

Tags

NGSS.HS-LS1-7

NGSS.HS-LS2-5

What do we call this lab set up?

• a barometer

• a respirometer

• a manometer

• a spirometer

Answer explanation

Respirometers measure respiration

What is the purpose of the cotton wool?

• to stop the maggots touching the soda lime

• to keep the oxygen in the space above the maggots

• to insulate the maggots from the cold

• to keep the boiling tube bright

Answer explanation

We have to protect the little beasties!

Tags

NGSS.MS-LS2-3

Why is the tube to the right in the boiling tube sealed?

• To allow gases to enter and exit the respirometer

• To stop gases entering and exiting the respirometer

• To keep the maggots warm

• There is no reason to seal that tube

Answer explanation

It has to be a closed system in order to measure the gases.

Tags

NGSS.HS-LS2-5

What do you expect to see happen?

• The liquid in the manometer will move UP the ruler

• The liquid in the manometer will move DOWN the ruler

• The liquid in the manometer will NOT move

• The liquid in the manometer will move UP and DOWN the ruler

Answer explanation

The liquid will move due. to a drop in pressure

Which best describes cellular respiration?

• the controlled release of energy from organic compounds to produce ATP

• the controlled releases of energy from inorganic compounds to produce ATP

• the controlled release of energy from organic compounds to produce ADP

• the controlled release of energy from inorganic compounds to produce ADP

Answer explanation

Blah, blah, blah, you should know this question by now!

Tags

NGSS.HS-LS1-7

NGSS.HS-LS2-3

When investigating the effect of temperature on the rate of respiration, why do you need tube Q with glass beads?

• To make sure it is a fair test - the volume of glass beads needs to be the same as the volume of soda lime

• It is a control variable - it allows you to see what happens without the soda lime

• It is a control - changes in temperature could also cause the bubble to move and this allows you to take that into account

• Glass beads have a high specific heat capacity so it makes it easier to maintain a constant temperature in the tubes

Answer explanation

Hmm, I hope this one made you think outside the box a little!

Tags

NGSS.HS-LS1-7

Which of the following is a true statement based on the data?

• The amount of oxygen consumed by germinating corn at 22°C is approximately twice the amount of oxygen consumed by germinating corn at 12°C.

• The rate of oxygen consumption is the same in both germinating and nongerminating corn during the initial time period from 0 to 5 minutes.

• The rate of oxygen consumption in the germinating corn at 12°C at 10 minutes is 0.4 ml O₂/minute.

• The rate of oxygen consumption is higher for nongerminating corn at 12°C than at 22°C.

• If the experiment were run for 30 minutes, the rate of oxygen consumption would decrease.

Answer explanation

You have to look at the graph, the answer is right there in front of you.

Tags

NGSS.HS-LS1-7

NGSS.HS-PS1-5

What is the rate of oxygen consumption in germinating corn at 12°C?

• 0.08 mL/min

• 0.04 mL/min

• 0.8 mL/min

• 1.00 mL/min

Answer explanation

Greaph reading skills are important! As is learning to spell!

Tags

NGSS.HS-LS1-7

NGSS.HS-LS2-5

Which of the following conclusions is supported by the data?

• The rate of respiration is higher in non-germinating seeds than in germinating seeds.

• Non-germinating peas are not alive, and show no difference in rate of respiration at different temperatures.

• The rate of respiration in the germinating seeds would have been higher if the experiment were conducted in sunlight.

• The rate of respiration increases as the temperature increases in both germinating and non-germinating seeds.

• The amount of oxygen consumed could be increased if pea seeds were substituted for corn seeds.

Answer explanation

It's all there on the graph.

Tags

NGSS.HS-LS1-7