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When would a cell most likely contain the most nucleotides?

A. S

B. G1

C. M

D. G2

Answer Explanation:

A cell copies its DNA during the S phase, and nucleotides are the building blocks of DNA. Thus, the step preceding the S phase, the G1 phase, is the phase of the cell cycle when the cell would contain the most nucleotides.

For a cell to divide into more cells, it must grow, copy its DNA, and produce new daughter cells. The cell cycle regulates cellular division. This process can either prevent a cell from dividing or trigger it to start dividing.

The cell cycle is an organized process divided into two phases: interphase and the M (mitotic) phase. During interphase, the cell grows and copies its DNA. After the cell reaches the M phase, division of the two new cells can occur. The G1, S, and G2 phases make up interphase.

  • G1: The first gap phase, during which the cell prepares to copy its DNA
  • S: The synthesis phase, during which DNA is copied
  • G2 : The second gap phase, during which the cell prepares for cell division

It may appear that little is happening in the cell during the gap phases. Most of the activity occurs at the level of enzymes and macromolecules. The cell produces things like nucleotides for synthesizing new DNA strands, enzymes for copying the DNA, and tubulin proteins for building the mitotic spindle. During the S phase, the DNA in the cell doubles, but few other signs are obvious under the microscope. All the dramatic events that can be seen under a microscope occur during the M phase: the chromosomes move, and the cell splits into two new cells with identical nuclei.

Therefore, the Correct Answer is B.

More Questions on TEAS 7 Science

  • Q #1: A researcher notices a positive correlation between the height of a plant and nutrient concentration over time. Based on this observation, what conclusion does he reach?

    A. The height of a plant increases in the absence and presence of the nutrients

    B. When the amount of nutrients available to the plant decreases, its height increases.

    C. The amount of nutrients available to a plant is independent of how tall the plant gets

    D. When the amount of nutrients available to the plant increases, its height also increases.

    Answer Explanation

    Because this is a positive correlation, if the nutrient concentration increases or decreases, plant height will either increase or decrease accordingly.

    While analyzing data, scientists tend to observe cause-and-effect relationships. These relationships can be quantified using correlations. Correlations measure the amount of linear association between two variables. There are three types of correlations:

    Positive correlation: 
    As one variable increases, the other variable also increases. This is also known as a direct correlation.

    Negative correlation: 
    As one variable increases, the other decreases. The opposite is true if one variable decreases. A negative correlation is also known as an inverse correlation or an indirect correlation.

    No correlation: 
    There is no connection or relationship between two variables.

  • Q #2: An atom has 28 protons, 32 neutrons, and 28 electrons. What is the name of this isotope?

    A. Nickel-32

    B. Nickel-60

    C. Germanium-56

    D. Germanium-60

    Answer Explanation

    The number of protons, 28, gives the atomic number, which identifies this atom as nickel. The mass is the number after the dash in the isotope name, which is determined by adding the numbers of protons and neutrons (28 + 32 = 60).

  • Q #3: Which of the following is supported by the cell theory?

    A. Cells are alive and recognized as the building blocks for life.

    B. Scientists can identify and differentiate cells by using a microscope

    C. Cells are produced from existing cells using meiosis instead of mitosis.

    D. Living things are composed of a single cell that remains undifferentiated

    Answer Explanation

    After scientists were able to view cells under the microscope they formulated the cell theory. One part of this theory concluded that all cells are alive. They also represent the basic unit of life.

    All living things are made of cells. Cells are the smallest structural units and basic building blocks of living things. Cells contain everything necessary to keep living things alive. Varying in size and shape, cells carry out specialized functions. This theory, or in-depth explanation, about cells consists of three parts:

    • All living things are composed of one or more cells.
    • Cells are alive and represent the basic unit of life.
    • All cells are produced from pre-existing cells.