1.
The cell theory states
Correct Answer
C. The cell is the basic unit of life.
Explanation
The cell theory states that the cell is the basic unit of life. This means that all living organisms are composed of cells and that cells are the smallest structural and functional units of life. The theory also states that all cells come from pre-existing cells, which supports the idea of cell division and reproduction. Additionally, the theory emphasizes that cells carry out all the necessary functions for life, such as metabolism and reproduction. Overall, the cell theory is a fundamental concept in biology that helps us understand the organization and functioning of living organisms.
2.
When you examine a cell using a light microscope, which might you be able to see?
Correct Answer
A. The nucleus only
Explanation
When examining a cell using a light microscope, it is possible to see the nucleus only. The nucleus is a distinct structure within the cell that contains the genetic material, DNA. Other structures such as the nucleolus and threads of chromatin may not be visible under a light microscope. The DNA double helix, which is the structure of DNA, is not visible under a light microscope as it requires more advanced techniques such as electron microscopy.
3.
The small size of cells best correlates with
Correct Answer
C. An adequate surface area for exchange of materials.
Explanation
The small size of cells best correlates with an adequate surface area for exchange of materials. This is because as cells increase in size, their surface area to volume ratio decreases, making it more difficult for materials to enter and exit the cell. Therefore, smaller cells have a larger surface area relative to their volume, allowing for efficient exchange of materials with the external environment.
4.
Which size relationship is incorrect?
Correct Answer
E. All of these are incorrect.
Explanation
The correct answer is that all of these size relationships are incorrect. This means that none of the statements about the size relationships are true.
5.
Which of the following structures are found in both plant and animal cells?
Correct Answer
D. Mitochondria
Explanation
Mitochondria are found in both plant and animal cells. They are responsible for producing energy in the form of ATP through cellular respiration. While plant cells also have chloroplasts for photosynthesis and a cell wall for structural support, animal cells lack these structures. Centrioles, on the other hand, are found only in animal cells and play a role in cell division. Therefore, the correct answer is mitochondria.
6.
Eukaryotic cells compensate for a low surface- to- volume ratio by
Correct Answer
C. Compartmentalizing their activities into organelles.
Explanation
Eukaryotic cells compensate for a low surface-to-volume ratio by compartmentalizing their activities into organelles. This allows them to increase the efficiency of their cellular processes by separating different functions and creating specialized environments within the cell. By having organelles such as the nucleus, mitochondria, and endoplasmic reticulum, eukaryotic cells can carry out various functions simultaneously and efficiently. This compartmentalization also helps in maintaining specific conditions required for different cellular processes, ensuring optimal functioning of the cell.
7.
The cell wall and capsule of bacteria
Correct Answer
D. Have projections called pili.
8.
What is synthesized by the nucleolus?
Correct Answer
C. Ribosomal subunits
Explanation
The nucleolus is responsible for synthesizing ribosomal subunits. Ribosomes are essential cellular structures involved in protein synthesis. The nucleolus, found within the nucleus of eukaryotic cells, produces the two subunits of ribosomes, the small and large subunits. These subunits are then transported out of the nucleolus and combined in the cytoplasm to form functional ribosomes. Therefore, the correct answer is ribosomal subunits.
9.
Ribosomes are found
Correct Answer
B. In the cytoplasm and on the rough endoplasmic reticulum.
Explanation
Ribosomes are found in the cytoplasm and on the rough endoplasmic reticulum. Ribosomes are responsible for protein synthesis and can be found free-floating in the cytoplasm or attached to the rough endoplasmic reticulum. This allows for the production of proteins both within the cytoplasm and for export out of the cell.
10.
The organelle that can modify a protein and determine its destination in the cell is the
Correct Answer
B. Golgi apparatus.
Explanation
The Golgi apparatus is responsible for modifying, sorting, and packaging proteins for transport to their final destination within the cell or for secretion outside the cell. It receives proteins from the endoplasmic reticulum and modifies them by adding sugars or lipids, which can determine their destination within the cell. The Golgi apparatus then packages the modified proteins into vesicles for transport to their appropriate location. The ribosome is responsible for protein synthesis, not modification or determining destination. The vacuole and lysosome have different functions unrelated to protein modification or destination determination.
11.
Which of these is not involved in protein synthesis and secretion?
Correct Answer
A. Smooth ER
Explanation
Smooth ER is not involved in protein synthesis and secretion. The smooth ER is responsible for lipid metabolism and detoxification, while the rough ER is involved in protein synthesis and secretion. The rough ER has ribosomes attached to its surface, which are responsible for protein synthesis. These proteins are then transported to other parts of the cell or secreted outside of the cell. Therefore, smooth ER is not involved in the process of protein synthesis and secretion.
12.
The central vacuole of plant cells may contain
Correct Answer
D. All of these are correct.
Explanation
The central vacuole of plant cells may contain flower color pigments, which contribute to the vibrant colors of flowers. It may also contain toxins that protect plants against herbivorous animals, acting as a defense mechanism. Additionally, the central vacuole stores sugars, which are essential for energy production and metabolism in plants. Therefore, all of these statements are correct as the central vacuole can contain flower color pigments, toxins, and sugars.
13.
__________ are produced by the Golgi apparatus and contain __________.
Correct Answer
C. Lysosomes, enzymes
Explanation
Lysosomes are produced by the Golgi apparatus and contain enzymes. Lysosomes are membrane-bound organelles that contain various hydrolytic enzymes. These enzymes are responsible for breaking down waste materials, cellular debris, and foreign substances. Lysosomes play a crucial role in maintaining cellular homeostasis and are involved in processes such as autophagy and apoptosis.
14.
Vesicles from the ER most likely are on their way to
Correct Answer
C. The Golgi apparatus.
Explanation
Vesicles from the ER are most likely on their way to the Golgi apparatus. The Golgi apparatus is responsible for modifying, sorting, and packaging proteins and lipids that are synthesized in the ER. Vesicles transport these molecules from the ER to the Golgi apparatus for further processing and distribution to their final destinations within the cell.