1.
In what stage, does a Cell spend the majority of its life?
Correct Answer
D. Interphase
Explanation
Interphase is the stage in which a cell spends the majority of its life. During this stage, the cell grows, carries out its normal functions, and replicates its DNA in preparation for cell division. It is the longest phase of the cell cycle and accounts for about 90% of the cell's life. In contrast, Telophase, Mitosis, and Meiosis are all stages of cell division that occur after Interphase. Therefore, the correct answer is Interphase.
2.
________________________ is the division of the cytoplasm of the cell.
Correct Answer
Cytokinesis
Explanation
Cytokinesis is the process of dividing the cytoplasm of a cell. After the cell's nucleus has divided during mitosis or meiosis, cytokinesis occurs to separate the two resulting daughter cells. During cytokinesis, a contractile ring of proteins forms around the equator of the cell, gradually constricting and eventually pinching the cell into two separate cells. This division ensures that each daughter cell receives a complete set of genetic material and organelles, allowing for growth and development.
3.
_________________ results in new cells with genetic material that is identical to the original cell.
Correct Answer
Mitosis
Explanation
Mitosis is a type of cell division that results in the production of two daughter cells, each having the same number and type of chromosomes as the parent cell. This process is responsible for the growth, development, and repair of tissues in multicellular organisms. During mitosis, the genetic material of the parent cell is replicated and evenly distributed to the daughter cells, ensuring that they are genetically identical to the original cell. Therefore, mitosis is the correct answer as it accurately describes the process that leads to the production of new cells with identical genetic material.
4.
__________________ reduces the chromosome number by half in new cells.
Correct Answer
Meiosis
Explanation
Meiosis is a type of cell division that occurs in sexually reproducing organisms. It involves two rounds of division, resulting in the production of four daughter cells, each with half the number of chromosomes as the parent cell. This reduction in chromosome number is crucial for sexual reproduction, as it ensures that when sperm and egg cells fuse during fertilization, the resulting offspring will have the correct number of chromosomes. Therefore, meiosis is the process that reduces the chromosome number by half in new cells.
5.
What is the type of cell divison that relults in the production of gameytes?
Correct Answer
B. Meiosis
Explanation
Meiosis is the type of cell division that results in the production of gametes. During meiosis, a diploid cell undergoes two rounds of division to produce four haploid cells, called gametes. These gametes have half the number of chromosomes as the original cell, allowing for genetic diversity when they combine during fertilization. This process is essential for sexual reproduction in organisms, as it ensures the correct number of chromosomes in the offspring.
6.
A human being has _____________ pairs of chromosomes.
Correct Answer
23, chromosomes
Explanation
Their are 23 pairs and 46 single chromatids.
7.
In prophase the nuclear membrane ___________________________.
Correct Answer
disappears
Explanation
During prophase, the nuclear membrane disappears. This is because prophase is the first stage of mitosis, where the cell prepares for division. The disappearance of the nuclear membrane allows the DNA to condense and form chromosomes, which are necessary for the separation of genetic material during cell division. The breakdown of the nuclear membrane also allows for the formation of the mitotic spindle, which helps in the movement and alignment of chromosomes. Therefore, the disappearance of the nuclear membrane is a crucial step in the initiation of cell division.
8.
The final stage in mitosis is ________________________.
Correct Answer
telophase
Explanation
The final stage in mitosis is telophase. During telophase, the chromosomes have reached opposite poles of the cell and begin to decondense. Nuclear envelopes start to form around each set of chromosomes, and the spindle fibers disassemble. This stage marks the completion of nuclear division, preparing the cell for cytokinesis, where the cytoplasm divides to form two separate daughter cells.
9.
What phase is shown below?
Correct Answer
D. Telophase
Explanation
The given image shows a stage in cell division where the chromosomes have reached opposite poles of the cell and are starting to decondense. This stage is known as telophase. During telophase, a new nuclear envelope begins to form around each set of chromosomes, and the cell starts to pinch in the middle, preparing for cytokinesis.
10.
What phase is shown below?
Correct Answer
C. Anaphase
Explanation
The phase shown below is anaphase. Anaphase is the stage of cell division where the sister chromatids separate and move towards opposite poles of the cell. This is facilitated by the shortening of microtubules and the pulling force exerted by the spindle fibers. The chromosomes can be seen clearly separated and moving towards the poles in the image, indicating that it is in the anaphase stage.
11.
What phase is shown below?
Correct Answer
B. Metaphase
Explanation
The phase shown in the image is metaphase. This can be inferred from the fact that during metaphase, the chromosomes align along the equator of the cell, forming a single line called the metaphase plate. This alignment is clearly visible in the image, indicating that the cell is in metaphase.
12.
What phase is shown below?
Correct Answer
A. Prophase
Explanation
The phase shown in the image is prophase. This can be determined by the visible condensation and coiling of the chromosomes, as well as the breakdown of the nuclear membrane. Additionally, the formation of the spindle fibers can also be observed in prophase.
13.
What can happen when cell division goes wrong?
Correct Answer
A. Cancer
Explanation
When cell division goes wrong, it can lead to the development of cancer. Cancer occurs when cells divide uncontrollably and form a mass of abnormal cells called a tumor. These abnormal cells can invade nearby tissues and spread to other parts of the body, disrupting normal bodily functions. Therefore, the correct answer is cancer.
14.
_________________ forms between poles of a cell during mitosis and meiosis.
Correct Answer
spindle fibers, Spindle Fibers
Explanation
Spindle fibers are formed between the poles of a cell during both mitosis and meiosis. These fibers play a crucial role in the movement and separation of chromosomes during cell division. They attach to the centromeres of the chromosomes and help in pulling them apart to opposite poles of the cell. The correct answer, "spindle fibers," refers to these structures, which are essential for the proper distribution of genetic material during cell division.
15.
How do the chromosomes become different from each other in meiosis?
Correct Answer
C. They "cross over"
Explanation
During meiosis, chromosomes become different from each other through a process called "crossing over." This occurs during prophase I, where homologous chromosomes exchange genetic material. Crossing over leads to the exchange of alleles between chromosomes, resulting in the formation of new combinations of genes. This process is crucial for genetic variation and diversity among offspring.
16.
___________________ is the cell phase where the chromosomes line up at the center and attach to the spindle fibers.
Correct Answer
Metaphase
Explanation
Metaphase is the correct answer because it is the cell phase in which the chromosomes align themselves along the center of the cell, forming a single line called the metaphase plate. During this phase, the spindle fibers attach to the chromosomes at their centromeres, ensuring that each chromosome will be evenly divided during cell division. This alignment and attachment of chromosomes in metaphase is crucial for the accurate separation of genetic material during the subsequent phase of cell division.
17.
____________________ is the stage where the ________________ _______________ begin to pull the chromosomes apart to opposite poles.
Correct Answer
A. Anaphase, spindle fibers
Explanation
During anaphase, the spindle fibers begin to pull the chromosomes apart to opposite poles. This is the stage in mitosis where the sister chromatids, previously attached at the centromere, separate and are pulled towards opposite ends of the cell by the spindle fibers. The spindle fibers are responsible for the movement and positioning of the chromosomes during cell division.
18.
How many chromosomes are there during mitosis in a diploid cell?
Correct Answer
46, fourty six, 23 pairs, 46 chromosomes
Explanation
During mitosis, the number of pairs of chromosomes remains the same as in the cell's diploid (2n) state. In humans, for example, there are typically 23 pairs of chromosomes, for a total of 46 chromosomes in a diploid cell. During mitosis, these chromosomes replicate, resulting in two sister chromatids per chromosome.