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. When magnesium metal reacts with hydrochloric acid, hydrogen gas is produced. What evidence suggests a chemical reaction is occurring?

A. A change in color
B. The formation of a gas
C. Dissolving in a liquid
D. No change in temperature

Correct answer: B

Rationale: The formation of a gas is evidence of a chemical reaction occurring. In this case, when magnesium metal reacts with hydrochloric acid, hydrogen gas is produced, indicating a chemical change is taking place. The production of gas is a clear indication of a chemical reaction, as new substances are being formed. A change in color might suggest a physical change, dissolving in a liquid could be a physical or chemical change depending on the context, and no change in temperature does not necessarily indicate a chemical reaction, as some reactions are endothermic or release small amounts of heat that may not be easily noticeable.

3. What is the temperature of 35°C in Kelvin?

A. 220
B. 238
C. 308
D. 345

Correct answer: C

Rationale: To convert Celsius to Kelvin, add 273.15 to the Celsius temperature. In this case, 35°C + 273.15 = 308.15 K. Therefore, the correct answer is 308 K. Choice A (220) is incorrect as it does not account for adding 273.15 to convert to Kelvin. Choice B (238) is incorrect as it is not the result of adding 273.15 to 35°C. Choice D (345) is incorrect as it is not the correct conversion of 35°C to Kelvin.

4. Which of the following is a strong acid?

A. Acetic acid (CH₃COOH)
B. Hydrochloric acid (HCl)
C. Citric acid
D. Carbonic acid (H₂CO₃)

Correct answer: B

Rationale: Hydrochloric acid (HCl) is a strong acid because it completely ionizes in water to produce hydrogen ions, leading to a high concentration of H⁺ ions in solution. This characteristic makes it a strong acid. Acetic acid (CH₃COOH), citric acid, and carbonic acid (H₂CO₃) are weak acids as they only partially ionize in water, resulting in a lower concentration of H⁺ ions compared to strong acids. Therefore, hydrochloric acid is the correct choice as a strong acid.

5. Which of these pairs represents an example of convergent evolution?

A. Humans and chimpanzees
B. Bats and birds
C. Dolphins and sharks
D. Snakes and earthworms

Correct answer: B

Rationale: Convergent evolution refers to the process by which different species independently evolve similar traits or characteristics due to similar environmental pressures. In the case of bats and birds, both have evolved wings for flight despite not sharing a recent common ancestor with wings. Bats are mammals, while birds are avians, yet they both have wings adapted for flight, which is a classic example of convergent evolution. A) Humans and chimpanzees share a common ancestor and have not independently evolved similar traits. C) Dolphins and sharks are not closely related, and their similarities are due to adaptations to their aquatic environment rather than convergent evolution. D) Snakes and earthworms belong to different classes (reptiles and annelids, respectively) and do not share recent common ancestors, making their similarities not a result of convergent evolution.