1.
Which of the following processes starts the stages of mitosis?
Correct Answer
B. Condensation of chromatin fiber
Explanation
Condensation of chromatin fiber is the correct answer because it is the initial step in mitosis. During this stage, the loosely packed chromatin fibers condense and form visible chromosomes. This condensation is necessary for the accurate separation of genetic material during cell division. The other options mentioned, such as DNA replication, development of spindle fibers, and dissolving of the nuclear membrane, are important processes that occur during mitosis but they occur after the condensation of chromatin fiber.
2.
Which of the following phases would you find the cell creating ribosomes for protein synthesis?
Correct Answer
A. G1
Explanation
During the G1 phase of the cell cycle, the cell prepares for DNA replication and protein synthesis. Ribosomes, which are responsible for protein synthesis, are created during this phase. Therefore, it is in the G1 phase that the cell would be creating ribosomes for protein synthesis.
3.
Which of the following stages would this picture best represent?
Correct Answer
A. Prophase
Explanation
This picture best represents the stage of Prophase because it shows condensed chromosomes, which is a characteristic feature of this stage. In Prophase, the nuclear envelope starts to break down, and the chromosomes become visible as they condense. This picture accurately depicts these key events of Prophase.
4.
Which of the following stages of mitosis would this picture best represent?
Correct Answer
C. Anaphase
Explanation
This picture best represents anaphase because it shows the separation of sister chromatids. In anaphase, the spindle fibers pull the sister chromatids apart towards opposite poles of the cell. This process ensures that each daughter cell will receive a complete set of chromosomes.
5.
Which of the following stages of mitosis would this picture best represent?
Correct Answer
A. Prometaphase
Explanation
This picture best represents the stage of prometaphase in mitosis. In prometaphase, the nuclear envelope breaks down, allowing the chromosomes to become more condensed and visible. The picture appears to show condensed chromosomes and a lack of a nuclear envelope, which are characteristic of prometaphase. Additionally, the chromosomes are not aligned at the center of the cell, ruling out metaphase. The lack of separation or movement of chromosomes also rules out anaphase. There is no evidence of cytokinesis or cell division, ruling out telophase.
6.
Which of the following stages of mitosis best describes the picture below?
Correct Answer
D. Telophase
Explanation
The picture provided shows a stage of mitosis where the chromosomes have reached the opposite poles of the cell and are starting to decondense. This stage is known as telophase, which is characterized by the formation of two daughter nuclei and the completion of cell division.
7.
Which of the following stages of mitosis would best describe the picture below?
Correct Answer
B. Metaphase
Explanation
The picture shows chromosomes aligned along the equatorial plane of the cell, which is characteristic of metaphase in mitosis. During metaphase, the spindle fibers attach to the kinetochores of the chromosomes and align them at the center of the cell. This alignment ensures that each daughter cell will receive the correct number of chromosomes during cell division.
8.
Which of the following would best describe what this picture is showing?
Correct Answer
A. Interphase
Explanation
The picture is showing interphase, which is the phase of the cell cycle where the cell prepares for cell division. During interphase, the cell grows, replicates its DNA, and carries out normal cellular functions. This phase is characterized by a visible nucleus and distinct nuclear membrane. It is the longest phase of the cell cycle and is essential for the cell to undergo successful division.
9.
Which of the following would you find DNA being replicated?
Correct Answer
A. Interphase
Explanation
DNA replication occurs during the interphase of the cell cycle. Interphase is the period of the cell cycle where the cell prepares for cell division by growing, carrying out normal cellular functions, and replicating its DNA. During interphase, the DNA is duplicated so that each resulting daughter cell will have a complete set of genetic material. Therefore, DNA replication would be found during interphase.
10.
Which of the following would you find DNA being replicated?
Correct Answer
B. S
Explanation
DNA replication occurs during the S phase of the cell cycle. In this phase, the cell's DNA is duplicated in preparation for cell division. The S phase follows the G1 phase, where the cell grows and prepares for DNA replication. After DNA replication in the S phase, the cell enters the G2 phase, where it continues to grow and prepares for mitosis. Mitosis is the process of cell division, where the duplicated DNA is distributed to two daughter cells. Therefore, DNA replication specifically occurs during the S phase.
11.
Attachment of the spindle fibers to the centromeres of duplicated chromosomes occurs in which stage of mitosis?
Correct Answer
A. Prometaphase
Explanation
During prometaphase, the nuclear envelope breaks down, allowing the spindle fibers to interact with the chromosomes. The spindle fibers attach to the centromeres of duplicated chromosomes, preparing them for proper alignment and separation. This stage is characterized by the movement and reorganization of the chromosomes, as they are captured by the spindle fibers and begin to migrate towards the center of the cell. Therefore, the attachment of the spindle fibers to the centromeres of duplicated chromosomes occurs in prometaphase.
12.
The central alignment of chromosomes by the spindle microtubules occurs in which of the following stages of mitosis?
Correct Answer
B. Metaphase
Explanation
During metaphase of mitosis, the spindle microtubules align the chromosomes at the center of the cell. This alignment is necessary for the equal separation of chromosomes during the subsequent stage of mitosis, known as anaphase. In metaphase, the chromosomes are attached to the spindle fibers at their centromeres, and the microtubules exert tension on the chromosomes, ensuring their proper alignment at the metaphase plate. Once all the chromosomes are aligned, the cell can proceed to anaphase, where the sister chromatids are separated and pulled towards opposite poles of the cell.
13.
The development of the nuclear envelope occurs in which of the following stages of mitosis?
Correct Answer
D. Telophase
Explanation
During telophase, the nuclear envelope reforms around the separated chromosomes, marking the end of mitosis. In prophase, the nuclear envelope breaks down to allow the chromosomes to condense and become visible. Metaphase is the stage where the chromosomes align in the middle of the cell. Anaphase is when the sister chromatids are pulled apart towards opposite ends of the cell. Therefore, the correct answer is telophase, as this is the stage where the nuclear envelope is reassembled.
14.
TRUE or FALSE: Metaphase and Telophase basically have opposite processes occurring.
Correct Answer
B. FALSE
Explanation
Metaphase and Telophase do not have opposite processes occurring. Metaphase is a stage in mitosis where the chromosomes align at the center of the cell, while Telophase is the final stage where the chromosomes decondense and nuclear envelopes form around each set of chromosomes. These processes are not opposite but rather sequential stages in the cell division process.
15.
The contraction of microtubules to separate sister chromatids occurs in which of the following stages of mitosis?
Correct Answer
C. Anaphase
Explanation
During anaphase of mitosis, the microtubules contract and pull the sister chromatids apart towards opposite ends of the cell. This process ensures that each resulting daughter cell receives a complete set of chromosomes. In prophase, the chromosomes condense and the spindle apparatus forms. In metaphase, the chromosomes align at the center of the cell. In telophase, the nuclear envelope reforms and the chromosomes decondense. Therefore, anaphase is the correct stage in which the contraction of microtubules separates the sister chromatids.