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. b
27. a
Um, are you sure?
-MC
ayy lmao
To answer question 26, we need to understand why plant cells contain both chloroplasts and mitochondria. The chloroplasts are responsible for photosynthesis, where they capture energy from sunlight and convert it into chemical energy in the form of glucose (sugar). On the other hand, mitochondria are involved in cellular respiration, a process that converts glucose into ATP, which is the usable form of energy for the cell.
Option a states that in the light, plants are photosynthetic autotrophs, meaning they can produce their own food through photosynthesis. In the dark, they are heterotrophs, meaning they rely on obtaining food from external sources. While this statement is partially true, it doesn't directly address why plant cells require both chloroplasts and mitochondria.
Option b correctly suggests that if plants cannot produce enough ATP (energy) during photosynthesis, they can generate it through cellular respiration. This is an important aspect as plants might not always have access to sunlight or may require more energy than can be obtained through photosynthesis alone.
Option c provides a valid explanation as it mentions that sugars produced in chloroplasts during photosynthesis can be stored in the plant for later use during cellular respiration. This highlights the interconnectedness and symbiotic relationship between these two organelles within plant cells.
Option d incorrectly suggests that chloroplasts are only found in leaves and stems, while mitochondria are solely present in roots. In reality, both chloroplasts and mitochondria can be found in various plant cell types and tissues. Therefore, option d is not the best answer.
For question 27, we need to consider the similarities between aerobic and anaerobic respiration. Let's analyze the options:
Option a states that ATP is produced during glycolysis. This is true for both aerobic and anaerobic respiration. Glycolysis is the initial step of cellular respiration where glucose is broken down into pyruvate, and a small amount of ATP is produced.
Option b suggests that pyruvate is broken down to ethanol or lactate. While this is true for anaerobic respiration, during aerobic respiration, pyruvate is further broken down in the mitochondria.
Option c states that the electron transport chain pumps hydrogen ions across a membrane, which is a characteristic of both aerobic and anaerobic respiration. The electron transport chain is responsible for the majority of ATP production during cellular respiration.
Option d correctly mentions that an organic hydrogen acceptor recycles NAD+, which is an important step in both aerobic and anaerobic respiration. During the electron transport chain, NAD+ is used as an electron carrier and is recycled back to its oxidized form by accepting hydrogen.
Therefore, the correct answers are:
26. c. Sugars are produced in chloroplasts during photosynthesis. These sugars can be stored in the plant for later use during cellular respiration.
27. a. ATP is produced during glycolysis.
c. The electron transport chain pumps hydrogen ions across a membrane.
d. An organic hydrogen acceptor recycles NAD+.