Biology Lab: Cell Respiration

Question 1

What is the purpose of the lab?

Answer 1

To understand the applications of photosynthesis and what allows it to occur such as chlorophyll pigments and light absorption

Question 2

What is the procedure for cell respiration?

Answer 2

1. Obtain 3 test tubes with 3 stopped
2. Test Tube 1: 15 dry beans
   Test Tube 2: 15 soaked beans
3. Pack a cotton in the test tube just above a 1 cm above the beans
4. Place one bead of KOH atop the cotton in each tube
5. Insert the stopper and seal tight
6. Add methlyne blue to each piper and submerge both in water and place weight to stop floating. Place thermometer to read the temperature
7. Allow air pressure to equalize in test tube and for temperature to be the same in both
8. Record the position of the marker droplet in each pipet and take 2 minute intervals for the next 20 minutes
9. Dispose of KOH pellets in the waste beaker

Question 3

What bean has the most volume?

Answer 3

The soaked beans have the most volume from oxygen consumption since they have active cells that utilize energy

Question 4

If you perform the experiment without adding the KOH pellets to the test tubes, what results would you predict?

Answer 4

It will not have accurate results in analyzing O2 consumption since the KOH absorbs the CO2. Without the pellets, the CO2 will be reduced by pushing air out rather than in.

Question 5

Oxygen is required for aerobic respiration. What biological process is the source of the oxygen found in the atmosphere?

Answer 5

Photosynthesis provides most O2 in the air

Question 6

Do you predict that urgerminated beans will consume oxygen?

Answer 6

They will consume it at low rates or none at all. This is because the ungerminated beans are dormant and do not need to make a lot of energy

Question 7

Cellular respiration burns organic molecules as fuel for energy. In the beans, where did the organic fuel for cellular respiration come from?

Answer 7

Beans have stored glucose provided by parent plant

Question 8

How will the fully-grown bean plants obtain organic fuels for cellular respiration> What is the source of carbon for these organic molecules?

Answer 8

As adults, plants produces their own glucose from photosynthesis. During the Calvin cycle, CO2 is used as the source of carbon and is made into G3P using ATP and NADPPH