Apple FRQ

Apple: c 1) Researchers also study apple trees that have been genetically modified so that the DNA binding domain of the transcription factor that stimulates expression of the PAL enzyme has been deleted. The researchers repeat the ground cover experiment with the genetically modified apple trees. Predict the effect of the two ground covers on pigment concentrations in the genetically modified apples.

Both types of ground covers won't have an effect on pigment concentrations in these genetically modified trees.

Apple: b 2) Justify the use of genetically identical apple trees as a controlled factor in the experiment.

It allows to see the difference in pigment concentration between the 2 experimental treatment groups.

Apple: c 2) Provide reasoning to justify your prediction.

Since PAL can't be produced. the amount of light doesn't matter since it won't affect the activation of PAL.

Apple: b 1) Identify the variable in the researchers' experiment that is dependent on the percent of reflected light the apple trees receive.

The dependent variable is the concentration of pigments in the apples.

Apple: d 2) In leaves, the PAL enzyme is also required for the production of other pigment molecules that are capable of absorbing UV and other radiation from the sun. Explain how the relationship between light and pigment production might serve as a protective mechanism for the cells of the apple tree

The increase of pigment production in leaves in response to more sunlight will reduce DNA damage from radiation.

Apple: a Using the information provided in Figure 2, explain the role of light in the activation of the PAL enzyme.

The light activates phosphatase, which removes the phosphate group from the PAL enzyme, activating it.

Apple: b 4) Calculate the percent change in the average concentration of flavonoids in apples grown with the reflective ground cover compared with the apples grown with the grass ground cover.

The percent change is 52.19% (44.5-29.24)/29.24 = 0.5218878 52.19

Apple: d 1) Based on the information provided in Figure 2, predict the effect of a constantly active kinase on flavonoid pigment production.

The production of flavonoid will decrease.

Apple: b 3) Using the data provided, describe the effect of the different ground covers on the percent of light reflected

The reflective group cover reflects more light.

Apple: d 3) Explain how the PAL enzyme interacts with its substrate in the absence of light.

They won't interact without light because the phosphate group is still attached to PAL, leaving it in an inactive state.