1.
Energy is released from ATP when
Correct Answer
D. A pHospHate group is removed.
Explanation
ATP (adenosine triphosphate) is a molecule that stores and releases energy in cells. It consists of a molecule of adenosine and three phosphate groups. When a phosphate group is removed from ATP by hydrolysis, energy is released. This is because the high-energy phosphate bond is broken, resulting in the formation of ADP (adenosine diphosphate) and inorganic phosphate. This energy release is used by cells for various processes such as muscle contraction, active transport, and synthesis of molecules. Therefore, the correct answer is that energy is released from ATP when a phosphate group is removed.
2.
In the Calvin cycle
Correct Answer
E. All of these
Explanation
In the Calvin cycle, all of the mentioned processes occur. Carbon dioxide is used to create organic molecules, energy in the form of ATP is used, NADPH is required, and glucose is formed. This cycle is a series of chemical reactions that take place in the chloroplasts of plants, and it is responsible for converting carbon dioxide into glucose, a process known as carbon fixation. So, all of the given statements are true and contribute to the overall functioning of the Calvin cycle.
3.
Where do the light-dependent reactions take place?
Correct Answer
C. In the thylakoid membranes
Explanation
The light-dependent reactions of photosynthesis occur in the thylakoid membranes. These reactions involve the absorption of light energy by chlorophyll molecules, which are located in the thylakoid membranes. The energy from the absorbed light is used to convert water into oxygen and to generate energy-rich molecules like ATP and NADPH. Therefore, the thylakoid membranes play a crucial role in capturing and converting light energy into chemical energy that can be used in the subsequent steps of photosynthesis.
4.
In the light-dependent reactions
Correct Answer
B. ATP and NADpH form
Explanation
In the light-dependent reactions, ATP and NADPH form. This is because during the light-dependent reactions of photosynthesis, light energy is used to excite electrons in chlorophyll molecules. These excited electrons are then transferred through a series of electron carriers, ultimately leading to the formation of ATP and NADPH. ATP is a high-energy molecule that provides energy for various cellular processes, while NADPH is a reducing agent that provides the necessary electrons for the Calvin cycle, where carbon dioxide is fixed and glucose molecules are formed.
5.
ADP contains which of these sugars?
Correct Answer
B. Ribose
Explanation
ADP, or adenosine diphosphate, is a molecule that consists of an adenine base, a ribose sugar, and two phosphate groups. Therefore, the correct answer is ribose, as it is one of the sugars present in ADP.
6.
ATP releases energy when a bond is broken between
Correct Answer
A. Two pHospHate groups.
Explanation
ATP (adenosine triphosphate) is a molecule that stores and releases energy in cells. It consists of three phosphate groups, a ribose sugar, and an adenine base. When ATP is used, it undergoes hydrolysis, where a bond between two phosphate groups is broken, resulting in the release of energy. Therefore, the correct answer is that ATP releases energy when a bond is broken between two phosphate groups.
7.
Energy is stored when
Correct Answer
C. A third pHospHate group is bonded to an ADP molecule to form ATP.
Explanation
Energy is stored when a third phosphate group is bonded to an ADP molecule to form ATP. This process is known as phosphorylation and it occurs during cellular respiration. ATP is the primary energy currency of cells and when the bond between the second and third phosphate groups is broken, energy is released for cellular processes. The addition of a third phosphate group to ADP requires energy input and results in the formation of ATP, which can then be used by cells for various energy-requiring reactions.
8.
Which of the following is NOT a part of adenosine diphosphate?
Correct Answer
A. Three pHospHate groups
Explanation
Adenosine diphosphate (ADP) is a molecule composed of adenosine, which consists of a ribose sugar and an adenine base, and two phosphate groups. The correct answer is "three phosphate groups" because ADP only has two phosphate groups. The presence of three phosphate groups would make it adenosine triphosphate (ATP), which is the molecule that stores and releases energy in cells.
9.
The three parts of an ATP molecule are
Correct Answer
C. Adenine, ribose, pHospHate.
Explanation
The correct answer is adenine, ribose, phosphate. ATP (adenosine triphosphate) is composed of three main components: adenine, a nitrogenous base; ribose, a five-carbon sugar; and phosphate groups. Adenine is a purine base, ribose is a pentose sugar, and phosphate groups are responsible for the high-energy bonds in ATP. Together, these three components form the structure of ATP, which serves as the primary energy currency in cells.
10.
Which of the following is NOT true?
Correct Answer
D. Used ATP is discarded by the cell as waste.
Explanation
ATP is not discarded by the cell as waste. Instead, it is recycled and regenerated in a continuous cycle known as the ATP cycle. When ATP is used by the cell to provide energy, it is converted into ADP (adenosine diphosphate) and inorganic phosphate. However, the ADP can be converted back into ATP through processes like cellular respiration, allowing it to be reused by the cell. Therefore, the statement that used ATP is discarded by the cell as waste is not true.
11.
Which of these is NOT part of cellular respiration?
Correct Answer
A. pHotosynthesis
Explanation
Photosynthesis is the process by which plants convert sunlight, water, and carbon dioxide into glucose and oxygen. It occurs in the chloroplasts of plant cells and is responsible for producing the energy-rich molecules needed for cellular respiration. On the other hand, cellular respiration is the process by which cells break down glucose and other organic molecules to release energy in the form of ATP. It consists of glycolysis, the Krebs cycle, and the electron transport chain. Therefore, photosynthesis is not part of cellular respiration, as it is a separate process that occurs in different organelles of the cell.
12.
The correct order of cellular respiration is
Correct Answer
C. Glycolysis-Kreb cycle- electron transport.
Explanation
The correct order of cellular respiration is glycolysis-Krebs cycle-electron transport. This is because glycolysis is the first step in cellular respiration, where glucose is broken down into pyruvate. The pyruvate then enters the Krebs cycle, also known as the citric acid cycle, where it is further broken down and produces energy-rich molecules. Finally, the energy-rich molecules generated in the Krebs cycle are used in the electron transport chain to produce ATP, the main energy currency of the cell.
13.
Cellular respiration always releases
Correct Answer
C. Energy.
Explanation
Cellular respiration is the process by which cells convert glucose and oxygen into carbon dioxide, water, and energy in the form of ATP. Oxygen is required for cellular respiration to occur, but it is not released as a byproduct. Carbon monoxide is a toxic gas that is not produced during cellular respiration. Lactic acid is produced during anaerobic respiration, not cellular respiration. Therefore, the correct answer is energy, as cellular respiration releases energy in the form of ATP.
14.
During aerobic cellular respiration, one molecule of glucose is used to produce how many ATP molecules?
Correct Answer
C. 36
Explanation
During aerobic cellular respiration, glucose is broken down in a series of metabolic reactions. In the process, each molecule of glucose produces a net gain of 36 ATP molecules. This occurs through the processes of glycolysis, the Krebs cycle, and oxidative phosphorylation. These reactions involve the conversion of glucose into pyruvate, the generation of high-energy molecules such as NADH and FADH2, and the subsequent production of ATP through the electron transport chain. Therefore, the correct answer is 36.
15.
Which of the following correctly summarizes aerobic cellar respiration?
Correct Answer
A. 602+C6H12O6-6CO2+6H2O+energy
Explanation
The correct answer summarizes aerobic cellular respiration as the process in which glucose (C6H12O6) and oxygen (O2) are converted into carbon dioxide (CO2), water (H2O), and energy. This process occurs in the mitochondria of cells and is essential for the production of ATP, the energy currency of the cell.
16.
Which of these if broken down during cellular respiration to release energy?
Correct Answer
A. Food molecules
Explanation
During cellular respiration, food molecules are broken down to release energy. This process involves the breakdown of glucose and other organic compounds through a series of chemical reactions, such as glycolysis, the Krebs cycle, and oxidative phosphorylation. These reactions release energy in the form of ATP (adenosine triphosphate), which is the primary energy currency of cells. Therefore, food molecules serve as the source of energy for cellular respiration.
17.
Which of these occurs in the cytoplasm?
Correct Answer
A. Glycolysis
Explanation
Glycolysis occurs in the cytoplasm. It is the first step in cellular respiration, where glucose is broken down into pyruvate molecules. This process occurs in the cytoplasm of the cell and does not require the presence of oxygen. Glycolysis is an anaerobic process and is common to both aerobic and anaerobic respiration.
18.
Lactic acid fermentation occurs in
Correct Answer
C. Muscle cells.
Explanation
Lactic acid fermentation occurs in muscle cells. During intense exercise, the body may not be able to supply enough oxygen to the muscles, leading to a switch from aerobic respiration to anaerobic respiration. In this anaerobic condition, glucose is broken down into lactic acid, which accumulates in the muscles, causing fatigue and muscle soreness. This process helps to provide a temporary energy source for the muscles when oxygen is limited.
19.
Muscle soreness can be caused by
Correct Answer
C. Lactic acid fermentation.
Explanation
Muscle soreness, also known as delayed onset muscle soreness (DOMS), is a common condition that occurs after intense exercise. It is believed to be caused by microdamage to muscle fibers, which triggers an inflammatory response. Lactic acid fermentation is the process that occurs in the absence of oxygen during intense exercise, leading to the production of lactic acid as a byproduct. This buildup of lactic acid can contribute to muscle soreness and fatigue. Therefore, lactic acid fermentation is the most likely cause of muscle soreness among the given options.
20.
When oxygen is present, what follows glycolysis?
Correct Answer
D. The Krebs cycle
Explanation
When oxygen is present, the next step after glycolysis is the Krebs cycle. This cycle, also known as the citric acid cycle or the tricarboxylic acid cycle, takes place in the mitochondria of cells. It involves a series of chemical reactions that further break down glucose and produce energy-rich molecules such as ATP and NADH. The Krebs cycle is an essential part of aerobic respiration, where oxygen acts as the final electron acceptor, allowing for the efficient production of energy in the form of ATP.
21.
Cellular respiration is an aerobic process because it must have which of the following to occur?
Correct Answer
C. Oxygen
Explanation
Cellular respiration is an aerobic process because it requires oxygen to occur. Aerobic respiration is the process by which cells convert glucose and oxygen into carbon dioxide, water, and energy in the form of ATP. Without oxygen, cells cannot efficiently produce ATP through aerobic respiration and would have to rely on anaerobic processes, which are less efficient. Therefore, the presence of oxygen is necessary for cellular respiration to take place.
22.
The Krebs cycle will NOT occur if
Correct Answer
B. Fermentation occurs.
Explanation
The Krebs cycle, also known as the citric acid cycle, is a central metabolic pathway that occurs in the mitochondria of cells. It is an aerobic process, meaning it requires the presence of oxygen to proceed. Oxygen acts as the final electron acceptor in the electron transport chain, which is an essential step for the Krebs cycle to occur. Fermentation, on the other hand, is an anaerobic process that occurs in the absence of oxygen. During fermentation, glucose is broken down to produce energy without the involvement of the Krebs cycle. Therefore, if fermentation occurs, it indicates the absence of oxygen, which prevents the Krebs cycle from taking place.
23.
A green pigment that traps energy from sunlight is
Correct Answer
C. ChloropHyll.
Explanation
Chlorophyll is the correct answer because it is a green pigment found in chloroplasts, which are the organelles responsible for photosynthesis in plants. Chlorophyll absorbs energy from sunlight and converts it into chemical energy, which is used to produce ATP and ultimately fuel the plant's growth and metabolism. Chlorophyll is located within the thylakoid membranes of the chloroplasts, where the light-dependent reactions of photosynthesis take place.
24.
During photosynthesis, the light reactions
Correct Answer
B. Release oxygen.
Explanation
During photosynthesis, the light reactions occur in the thylakoid membranes of chloroplasts. These reactions involve the absorption of light energy by chlorophyll and the conversion of this energy into chemical energy in the form of ATP and NADPH. One of the byproducts of these reactions is the release of oxygen gas (O2) into the atmosphere. This oxygen is a waste product of photosynthesis and is essential for the survival of aerobic organisms on Earth.
25.
Which of the following best summarizes the process of photosynthesis?
Correct Answer
B. 6CO2+6H2O+energy-C6H12O6+6O2
Explanation
The correct answer summarizes the process of photosynthesis, which is the conversion of carbon dioxide and water into glucose and oxygen using energy from sunlight. This process is represented by the equation 6CO2 + 6H2O + energy → C6H12O6 + 6O2.
26.
Plants take in the sun's energy by absorbing
Correct Answer
D. Sunlight.
Explanation
Plants take in the sun's energy through a process called photosynthesis, in which sunlight is converted into chemical energy. This energy is used to produce high-energy carbohydrates, such as glucose, which serve as the main source of fuel for the plant. Chlorophyll, found in chloroplasts, is the pigment that captures the sunlight and initiates the photosynthesis process. However, while chlorophyll and chloroplasts are essential components of photosynthesis, they are not directly responsible for absorbing the sun's energy. Therefore, the correct answer is sunlight.
27.
The Calvin cycle produces
Correct Answer
C. High-energy sugar.
Explanation
The Calvin cycle is a series of chemical reactions that occur in the chloroplasts of plants during photosynthesis. It uses energy from sunlight to convert carbon dioxide into high-energy sugar molecules, such as glucose. These high-energy sugars are then used by the plant as a source of energy for growth and other metabolic processes. Therefore, the correct answer is high-energy sugar.
28.
Which would you expect to increase the rate of photosynthesis?
Correct Answer
B. Decreasing the intensity of exposure to light
Explanation
Decreasing the intensity of exposure to light would be expected to increase the rate of photosynthesis. Photosynthesis is the process by which plants convert light energy into chemical energy to fuel their growth. By decreasing the intensity of light, the plant is able to optimize its energy absorption and utilization. This allows the plant to balance the amount of energy it receives with its ability to convert that energy into usable forms. As a result, the rate of photosynthesis increases as the plant is able to efficiently utilize the available light energy.