which of the following is a common characteristic of alkynes

ATI TEAS 7

TEAS 7 science quizlet

1. Which of the following is a common characteristic of alkynes?

A. They have a triple bond between carbon atoms.
B. They are saturated hydrocarbons.
C. They contain only single bonds.
D. They are aromatic compounds.

Correct answer: A

Rationale: The correct answer is A. Alkynes are hydrocarbons characterized by at least one triple bond between carbon atoms. This triple bond sets them apart from alkanes, which only have single bonds, and alkenes, which feature at least one double bond. The presence of a triple bond makes alkynes unsaturated hydrocarbons. Choice B is incorrect as alkynes are unsaturated hydrocarbons, not saturated. Choice C is incorrect because alkynes contain at least one triple bond, making them different from compounds with only single bonds. Choice D is incorrect because aromatic compounds have a distinct cyclic structure with resonance stabilization, a feature not shared by alkynes.

2. What is the function of the myelin sheath in a neuron?

A. To transmit electrical impulses
B. To insulate and speed up electrical signals
C. To produce neurotransmitters
D. To protect the neuron from damage

Correct answer: B

Rationale: The myelin sheath serves to insulate neurons and accelerate the transmission of electrical signals along the axon. This insulation helps in the efficient conduction of nerve impulses by preventing signal loss or leakage. Choice A is incorrect because the myelin sheath does not transmit electrical impulses itself but rather helps in the conduction. Choice C is incorrect as the myelin sheath is not responsible for producing neurotransmitters. Choice D is also incorrect as the primary function of the myelin sheath is not to protect the neuron from damage. Therefore, the correct answer is B, as it accurately describes the function of the myelin sheath in a neuron.

3. What is the main function of red blood cells?

A. Transport oxygen
B. Transport carbon dioxide
C. Regulate blood pressure
D. Regulate heart rate

Correct answer: A

Rationale: The correct answer is A: Transport oxygen. Red blood cells are primarily responsible for carrying oxygen from the lungs to the tissues in the body. Hemoglobin, a protein found in red blood cells, binds to oxygen in the lungs and releases it to cells throughout the body. This oxygen transport is essential for cellular respiration and energy production in the body. Red blood cells do not regulate blood pressure or heart rate; their main role is oxygen transport. Choices B, C, and D are incorrect because red blood cells do not transport carbon dioxide, regulate blood pressure, or regulate heart rate. These functions are primarily carried out by other components of the circulatory and regulatory systems.

4. Which of the following statements accurately characterizes the relationship between genes and chromosomes?

A. Each gene contains multiple chromosomes.
B. Each chromosome contains multiple genes.
C. Genes and chromosomes are two different things referring to the same entity.
D. Genes and chromosomes are not interchangeable terms and do not always occur in equal numbers.

Correct answer: B

Rationale: The correct answer is B: Each chromosome contains multiple genes. Genes, which are segments of DNA, are located on chromosomes and carry hereditary information. Chromosomes contain many genes, indicating that genes are part of the structure of chromosomes. Choice A is incorrect because genes do not contain chromosomes; rather, they are located on chromosomes. Choice C is incorrect as genes and chromosomes are distinct entities with different functions. Choice D is incorrect because genes and chromosomes are related but not in equal numbers; chromosomes contain multiple genes, but the number of genes can vary between chromosomes.

5. Which of the following vessels is responsible for pumping oxygenated blood to the body?

A. Right ventricle
B. Left ventricle
C. Pulmonary artery
D. Aorta

Correct answer: D

Rationale: The aorta is the correct answer because it is responsible for pumping oxygenated blood from the heart to the rest of the body. The aorta is the main artery that carries blood away from the heart and distributes it to all parts of the body, providing oxygen and nutrients to the tissues. Choices A, B, and C are incorrect. The right ventricle pumps deoxygenated blood to the lungs through the pulmonary artery, the left ventricle pumps oxygenated blood to the body through the aorta, and the pulmonary artery carries deoxygenated blood from the heart to the lungs for oxygenation.