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 of the following accurately describes the measurements?

A. They are both accurate and precise.
B. They are accurate but not precise.
C. They are precise but not accurate.
D. They are neither accurate nor precise.

Correct answer: B

Rationale: Accuracy refers to how close a measurement is to the true or accepted value, while precision refers to how close individual measurements are to each other. If the measurements are accurate but not precise, it means they consistently hit the target value but may vary in terms of how closely grouped they are. Choice B, 'They are accurate but not precise,' correctly describes the scenario where the measurements are on target but not consistently close to each other. Choice A is incorrect because it implies both accuracy and precision, which is not the case here. Choice C is incorrect because it suggests precision without accuracy, while choice D is incorrect as it indicates neither accuracy nor precision, which is not a typical scenario for measurements.

3. What is the primary function of the epiglottis in the respiratory system?

A. Filtration of air
B. Production of mucus
C. Prevention of food entering the trachea
D. Oxygen exchange in the alveoli

Correct answer: C

Rationale: The primary function of the epiglottis in the respiratory system is to prevent food from entering the trachea. During swallowing, the epiglottis covers the opening of the trachea, guiding food down the esophagus to the stomach and preventing it from entering the airway. This mechanism safeguards the respiratory system from foreign objects, ensuring proper air passage and avoiding potential choking hazards. Choices A, B, and D are incorrect: A) Filtration of air is mainly performed by the nasal hairs and the mucous membranes of the respiratory tract. B) Production of mucus is primarily carried out by the mucous glands in the respiratory system to trap particles and humidify the air. D) Oxygen exchange in the alveoli occurs in the lungs and is related to the process of respiration, not the function of the epiglottis.

4. Which types of molecules can move through a cell membrane by passive transport?

A. Complex sugars
B. Non-lipid soluble molecules
C. Oxygen
D. Molecules moving from areas of low concentration to areas of high concentration

Correct answer: C

Rationale: The correct answer is C: Oxygen. Small, non-polar molecules like oxygen can easily pass through the cell membrane by passive transport as they move down their concentration gradient without the need for energy input. Complex sugars (choice A) are typically too large to pass through the membrane by passive transport. Non-lipid soluble molecules (choice B) may require active transport mechanisms. Choice D describes active transport, where molecules move against their concentration gradient, requiring energy input.

5. What controls the involuntary, rhythmic contractions of the heart muscle?

A. Lungs
B. Brain
C. Spinal cord
D. Sinoatrial node (located within the heart)

Correct answer: D

Rationale: The correct answer is D: Sinoatrial node (located within the heart). The involuntary, rhythmic contractions of the heart muscle are controlled by a specialized group of cells located within the heart called the sinoatrial node (SA node). The SA node acts as the heart's natural pacemaker, producing electrical impulses that regulate the heart rate and synchronize the contractions of the heart muscle. Choices A, B, and C (Lungs, Brain, Spinal cord) are not responsible for directly influencing the rhythmic contractions of the heart muscle.