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What is the correct order of the stages of the cell cycle?

A. G1,S,G2,M

B. G2,S,G1,M

C. M,S,G2,G1

D. S,M,G1,G1

Answer Explanation:

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 A.

More Questions on TEAS 7 Science

  • Q #1: What body system is the skeletal system most closely associated with when hematopoiesis happens?

    A. Urinary system

    B. Digestive system

    C. Muscular system

    D. Cardiovascular system

    Answer Explanation

    The cardiovascular system is closely associated with hematopoiesis because it includes the heart and blood vessels, which are responsible for circulating blood throughout the body. Hematopoiesis, the process of blood cell formation, primarily occurs in the bone marrow, which is part of the skeletal system. However, the cardiovascular system plays a crucial role in transporting these blood cells to various parts of the body once they are produced in the bone marrow.

    So, while the skeletal system provides the site for hematopoiesis, the cardiovascular system is responsible for distributing the blood cells, making it the most closely associated system in this context.

  • Q #2: Mendel discovered the pattern associated with _____after developing a series of rules in genetics.

    A. epigenetics

    B. heredity

    C. heterogeneity

    D. taxonomy

    Answer Explanation

    Mendel was accurately able to predict the patterns of heredity by studying rules related to genetics. These rules helped shape his theory of heredity. Heredity is the characteristics offspring inherit from their parents. 

    From experiments with garden peas, Mendel developed a simple set of rules that accurately predicted patterns of heredity. He discovered that plants either self-pollinate or cross-pollinate, when the pollen from one plant fertilizes the pistil of another plant. He also discovered that traits are either dominant or recessive. Dominant traits are expressed, and recessive traits are hidden.

    Mendel’s Theory of Heredity

    To explain his results, Mendel proposed a theory that has become the foundation of the science of genetics. The theory has five elements:

    • Parents do not transmit traits directly to their offspring. Rather, they pass on units of information called genes.
    • For each trait, an individual has two factors: one from each parent. If the two factors have the same information, the individual is homozygous for that trait. If the two factors are different, the individual is heterozygous for that trait. Each copy of a factor, or gene, is called an allele.
    • The alleles determine the physical appearance, or phenotype. The set of alleles an individual has is its genotype.
    • An individual receives one allele from each parent.
    • The presence of an allele does not guarantee that the trait will be expressed.

  • Q #3: Which is classified as a type of acid-base reaction that produces a salt?

    A. Combination

    B. Decomposition

    C. Hydrolysis

    D. Neutralization

    Answer Explanation

    A neutralization reaction is a type of acid-base reaction where an acid and base react to form a salt and water. 

    In an aqueous solution, a base increases the hydroxide concentration (OH–), while an acid increases the hydrogen ion (H+) concentration. Sometimes, neutralization reactions also occur. This type of reaction happens when an acid and a base react with each other to form water and salt. Salt is typically defined as an ionic compound that includes any cation except H+ and any anion except OH–. Consider the following example of a neutralization reaction between hydrobromic acid (HBr) and potassium hydroxide (KOH).

    HBr+KOH→KBr+H2O

    Not all neutralization reactions proceed in the manner where all reactants are in the aqueous phase. In some chemical reactions, one reactant may be a solid. The neutralization reaction can still proceed to completion.