how does the structure of centromeres contribute to chromosome movement during mitosis

ATI TEAS 7

TEAS 7 science quizlet

1. How does the structure of centromeres contribute to chromosome movement during mitosis?

A. The centromere provides a binding site for spindle fibers, allowing chromosomes to be attached and manipulated.
B. The centromere serves as a dividing point between sister chromatids, ensuring their separation during anaphase.
C. The centromere maintains chromosome stability by preventing chromosomal breaks and rearrangements.
D. The centromere plays a role in DNA replication, ensuring accurate copying of the genetic material.

Correct answer: A

Rationale: A) The centromere provides a binding site for spindle fibers, which are microtubules that help move chromosomes during cell division. This attachment allows the chromosomes to be pulled towards opposite poles of the cell during mitosis. Therefore, the structure of centromeres directly contributes to chromosome movement during mitosis by facilitating the attachment and manipulation of chromosomes by the spindle fibers. B) While the centromere does serve as a dividing point between sister chromatids, ensuring their separation during anaphase, this function is more related to the segregation of chromosomes rather than their movement. C) The centromere does play a role in maintaining chromosome stability by ensuring proper chromosome segregation, but it is not primarily responsible for preventing chromosomal breaks and rearrangements. D) The centromere is not directly involved in DNA replication. Its main function is

2. Which type of waves do not require a medium for propagation?

A. Transverse waves
B. Longitudinal waves
C. Electromagnetic waves
D. Surface waves

Correct answer: C

Rationale: Electromagnetic waves do not require a medium for propagation as they consist of oscillating electric and magnetic fields that can travel through a vacuum. This property allows electromagnetic waves, such as light, radio waves, and X-rays, to propagate through space. In contrast, transverse and longitudinal waves require a medium (solid, liquid, or gas) for propagation. Transverse waves have vibrations perpendicular to the direction of energy transfer, while longitudinal waves have vibrations parallel to the direction of energy transfer. Surface waves, which are a combination of transverse and longitudinal waves, also need a medium for propagation. Understanding the distinction between these wave types is essential in various fields, including physics and communication technologies.

3. What effect does a catalyst have on a chemical reaction?

A. It speeds up the reaction.
B. It slows down the reaction.
C. It makes a reaction go in reverse.
D. It prevents a reaction from taking place.

Correct answer: A

Rationale: A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process. It works by providing an alternate pathway for the reaction to occur, lowering the activation energy needed for the reaction to proceed. As a result, more reactant molecules can overcome this energy barrier and participate in the reaction, leading to a faster overall reaction rate. This explanation contradicts choices B, C, and D as a catalyst does not slow down, reverse, or prevent a reaction; instead, it accelerates the reaction by facilitating a more efficient route for the reaction to take place. Therefore, the correct answer is that a catalyst speeds up the reaction.

4. Which of the following substances is an example of an acidic gas?

A. Nitrogen (N₂)
B. Carbon dioxide (CO₂)
C. Sulfur dioxide (SO₂)
D. Oxygen (O₂)

Correct answer: C

Rationale: The correct answer is C, Sulfur dioxide (SO₂). Sulfur dioxide is an acidic gas because when dissolved in water, it forms sulfurous acid, which imparts acidic properties. Nitrogen (N₂), carbon dioxide (CO₂), and oxygen (O₂) are not considered acidic gases. Nitrogen is a neutral gas, carbon dioxide forms a weakly acidic solution when dissolved in water, and oxygen is a neutral gas.

5. Which property of a substance refers to its ability to undergo a chemical change and form new substances?

A. Density
B. Mass
C. Reactivity
D. Volume

Correct answer: C

Rationale: Reactivity is the property of a substance that describes its ability to undergo a chemical change and form new substances through chemical reactions. Density, mass, and volume are physical properties of a substance and do not directly relate to its ability to undergo chemical changes. Density is the mass of a substance per unit volume, mass is the amount of matter present, and volume is the amount of space occupied by the substance. Reactivity specifically deals with how likely a substance is to engage in chemical reactions. Therefore, the correct answer is C - Reactivity.