Need help with these two:

26. Why do plant cells contain both choroplasts and mitochondria?
a. in the light, plants are photosynthetic autotrophs. In the dark, they are heterotrophs.
b. if plants can't produce enough ATP to make sugars during photosynthesis, they can produce it during cellular respiration
c. Sugars are produced in chloroplasts during photosynthesis. These sugars can be stored in the plan for later use during cellular respiration
d. The leaves, and sometimes, the stems of plants contain chloroplasts while the roots of plants contain mitochondria.

27. Which of the following is true for both aerobic and anaerobic respiration?
a. ATP is produced during glycolysis
b. Pyruvate is broken down to ethanol or lactate
c. the electron transport chain pumps hydrogen ions across a membrane
d. An organic hydrogen acceptor recycles NAD+

Thanks
-MC

26 = A

27 = A

You're sure?

-MC

To answer both questions, we need to understand the processes of photosynthesis and cellular respiration in plant cells.

26. The correct answer is c. Sugars are produced in chloroplasts during photosynthesis, and these sugars can be stored in the plant for later use during cellular respiration.

To understand why plant cells contain both chloroplasts and mitochondria, we need to know that chloroplasts are responsible for photosynthesis, while mitochondria are responsible for cellular respiration.

During photosynthesis, plants use chloroplasts to convert sunlight, water, and carbon dioxide into sugars (glucose) and release oxygen as a byproduct. This process takes place in the presence of light, and it is an essential process for plants to produce energy and organic compounds.

However, photosynthesis is not possible during the night or in the absence of light. In such situations, plants rely on cellular respiration, which takes place in mitochondria. Mitochondria break down the stored sugars (produced during photosynthesis) to generate ATP (adenosine triphosphate), which is the energy currency of cells.

Therefore, plant cells contain both chloroplasts and mitochondria because they need to perform photosynthesis during the day to produce sugars and store them, and cellular respiration during the night to break down those stored sugars and produce ATP for energy.

27. The correct answer is a. ATP is produced during glycolysis.

Aerobic respiration and anaerobic respiration are two different processes that occur within cells to generate ATP.

In aerobic respiration, which occurs in the presence of oxygen, glucose is completely broken down into carbon dioxide and water through a series of stages: glycolysis, the Krebs cycle, and the electron transport chain. During the glycolysis stage, which takes place in the cytoplasm, glucose is converted into pyruvate, producing a small amount of ATP.

In anaerobic respiration, which occurs in the absence of oxygen, glucose is partially broken down into either ethanol or lactate, depending on the organism or cell type. This process also includes glycolysis, but instead of proceeding to the Krebs cycle and electron transport chain, the pyruvate is converted into ethanol or lactate, and only a small amount of ATP is generated.

Therefore, irrespective of whether it is aerobic or anaerobic respiration, both processes involve glycolysis, which produces ATP.