Nursing Elites

1. Deuterium, a stable isotope of hydrogen, has a nucleus containing:

• A. A single proton
• B. A proton and a neutron
• C. Two protons and an electron
• D. Two neutrons

Correct answer: B

Rationale: Deuterium, as an isotope of hydrogen, has an atomic number of 1 and a mass number of 2. The nucleus of deuterium contains one proton (as in all hydrogen atoms) and one neutron, totaling 2 nucleons in the nucleus. Therefore, the correct answer is that deuterium's nucleus contains a proton and a neutron. Choices A, C, and D are incorrect. Deuterium is not just a single proton (A), doesn't have two protons and an electron (C), and doesn't contain two neutrons (D). The correct composition of deuterium's nucleus is one proton and one neutron.

2. What is the function of the endocrine system?

• A. To protect the body from infection
• B. To release digestive enzymes
• C. To break down food
• D. To regulate the sleep-wake cycle

Correct answer: B

Rationale: The correct answer is B. The endocrine system releases hormones that regulate various functions, including metabolism and growth. It is responsible for producing and releasing hormones that control processes such as metabolism, growth, and development. The digestive enzymes are released by the digestive system, not the endocrine system. Choices A, C, and D are incorrect because protecting the body from infection is primarily the role of the immune system, breaking down food is the function of the digestive system, and regulating the sleep-wake cycle is controlled by the circadian rhythm which is mainly influenced by the brain's hypothalamus and not the endocrine system.

3. What is the fundamental unit of the nervous system?

• A. Neuron
• B. Nerve
• C. Ganglion
• D. Neuroglia

Correct answer: A

Rationale: The correct answer is A: Neuron. Neurons are the fundamental building blocks of the nervous system. These specialized cells play a crucial role in transmitting information through electrical and chemical signals. While nerves are comprised of bundles of neurons and ganglia consist of clusters of nerve cell bodies located outside the central nervous system, neuroglia serve as support cells for neurons. Neurons are specifically responsible for processing and transmitting information within the nervous system, making them the essential unit of this complex system. Choices B, C, and D are incorrect as nerves are bundles of neurons, ganglia are clusters of nerve cell bodies outside the central nervous system, and neuroglia are support cells for neurons, not the fundamental units responsible for information processing and transmission.

4. What controls muscles by sending electrical impulses to the muscles?

• A. Blood vessels
• B. Nerves
• C. Hormones
• D. Neurons

Correct answer: B

Rationale: Nerves control muscles by transmitting electrical impulses that initiate muscle contractions. Blood vessels are responsible for transporting blood, not controlling muscles. Hormones are chemical messengers produced by glands to regulate bodily functions, not specifically controlling muscles. Neurons are the basic building blocks of the nervous system that transmit signals, but nerves are the specific structures that control muscles by sending electrical impulses.

5. A botanist wants to determine if environmental temperature affects root growth. What is the independent variable in this study?

• A. Temperature
• B. Seedlings
• C. Light
• D. Root length

Correct answer: A

Rationale: The correct answer is 'Temperature.' In an experiment, the independent variable is the factor that is deliberately manipulated or changed by the researcher. In this study, the botanist is specifically investigating how environmental temperature affects root growth, making temperature the independent variable. Choice B, 'Seedlings,' and Choice C, 'Light,' are not the independent variables in this context as they are not the factors being intentionally changed or manipulated. Choice D, 'Root length,' is the dependent variable, as it is the outcome that is being measured or observed in response to the changes in the independent variable, temperature.

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