subject
Biology, 26.02.2020 01:53 msmalls0396583

All organisms are dependent on a healthy carbon dioxide-oxygen balance. Photosynthesis and cellular respiration are key processes in maintaining this balance. Your class is conducting a lab experiment to investigate the relationship between photosynthesis and cellular respiration by observing how carbon dioxide cycles through a biological system. To conduct the experiment, each group set up four test tubes containing 30 ml distilled water and 3 ml of bromothymol blue. Bromothymol blue is a pH indicator that changes from blue (alkaline) to yellow (acid). When carbon dioxide dissolves in water, it produces carbonic acid, turning the indicator from blue to yellow. The level of CO2 was inferred from a change in the indicator color.

A snail, elodea (aquatic plant), or both were added to the tubes and they were stoppered. Tubes were placed under a grow light for 24 hours and the results recorded. The test tubes were then covered for 24 hours to produce a dark environment and the results recorded. Which statement best explains the change in Test Tube D from the light setup to the dark setup.

A) The rate of photosynthesis decreased in the dark, thus the elodea used less CO2. The elodea and snails produced less CO2 through cellular respiration, causing the CO2 to be in equilibrium, making the solution more neutral (yellow).

B) The rate of photosynthesis decreased in the dark, thus the elodea used less CO2. The elodea and snails continued to produce CO2 through cellular respiration, raising the level of CO2 in the tube, causing the solution to become more acidic (yellow).

C) The rate of photosynthesis decreased in the dark, thus the elodea used more CO2. The elodea and snails continued to consume CO2 through cellular respiration, lowering the level of CO2 in the tube, causing the solution to become more basic (yellow).

D) The rate of photosynthesis decreased in the dark, thus the elodea used less CO2. The elodea and snails continued to consume CO2 through cellular respiration, raising the level of CO2 in the tube, causing the solution to become more acidic (yellow).

Carbon DIoxide Production in Snails & Elodea

Test Tube Contents, Initial Color, Light Set Up, Dark Set Up

Tube A: control, green, green, green

Tube B: elodea, green, blue, green

Tube C: snail, green, yellow, yellow

Tube D: elodea and snail, green, green, yellow

ansver
Answers: 1

Another question on Biology

question
Biology, 21.06.2019 18:40
The oxidizing agent our bodies use to obtain energy from food is oxygen (from the air). if you breathe 15 times a minute (at rest), taking in and exhaling 0.5 l of air with each breath, what volume of air do you breathe each day? air is 21% oxygen by volume. what volume of oxygen do you breathe each day?
Answers: 1
question
Biology, 22.06.2019 00:40
There is a liquid capsule inside a cup full of liquid. the cup full of liquid has salt in it and the liquid capsule has no salt in it. in which direction will the solvent flow? a. the salt does not have to move b. from the capsule to the larger cup c. equally between the capsule and the cup d. from the larger cup to the capsule
Answers: 1
question
Biology, 22.06.2019 03:00
Me with these questions image attached
Answers: 2
question
Biology, 22.06.2019 03:20
What is one energy transformation that is taking place in the photo? radiant energy to thermal energy thermal energy to nuclear energy chemical energy to thermal energy radiant energy to chemical energy
Answers: 1
You know the right answer?
All organisms are dependent on a healthy carbon dioxide-oxygen balance. Photosynthesis and cellular...
Questions
question
Mathematics, 04.02.2020 11:59
Questions on the website: 13722367