Nursing Elites

1. What is the process by which RNA molecules are modified after transcription but before translation?

• A. Replication
• B. Splicing
• C. Editing
• D. Packaging

Correct answer: B

Rationale: B) Splicing is the correct answer. Splicing is the process by which non-coding regions (introns) are removed from pre-mRNA, and the remaining coding regions (exons) are joined together to form mature mRNA. This modification occurs after transcription but before translation. A) Replication is incorrect as replication is the process by which DNA is copied to produce a new DNA molecule, not RNA modifications. C) Editing may involve RNA editing, but it is not commonly used to describe the modification of RNA molecules after transcription. D) Packaging is not the correct term as it refers to the condensation and organization of DNA into chromatin in eukaryotic cells, not the modification of RNA molecules.

2. Smooth muscle is the only ____________ muscle in the body.

• A. Voluntary, striated
• B. Involuntary, non-striated
• C. Involuntary, striated
• D. Voluntary, non-striated

Correct answer: B

Rationale: Smooth muscle is the only involuntary, non-striated muscle type in the body. It is found in organs like the intestines and blood vessels, where it controls movements without conscious effort. Choice A is incorrect because voluntary muscles are under conscious control, while smooth muscle is involuntary. Choice C is incorrect because striations are not present in smooth muscle, unlike skeletal muscle. Choice D is incorrect because smooth muscle is not voluntary and lacks striations, making it different from skeletal muscle.

3. Which of the following types of muscle tissue is found attached to bones and allows for voluntary movement?

• A. Smooth muscle
• B. Cardiac muscle
• C. Skeletal muscle
• D. Connective tissue

Correct answer: C

Rationale: The correct answer is C: Skeletal muscle. Skeletal muscle is attached to bones and allows for voluntary movement, such as walking, running, and lifting objects. Smooth muscle, found in the walls of internal organs and blood vessels, is responsible for involuntary movements. Cardiac muscle is specific to the heart and controls involuntary contraction. Connective tissue, on the other hand, provides support and connects different structures in the body, but it is not responsible for voluntary movement like skeletal muscle.

4. What are the four main types of macromolecules that are essential for life?

• A. Carbohydrates, lipids, proteins, and nucleic acids
• B. Carbohydrates, proteins, fats, and vitamins
• C. Minerals, vitamins, proteins, and fats
• D. Carbohydrates, lipids, proteins, and hormones

Correct answer: A

Rationale: The correct answer is A: Carbohydrates, lipids, proteins, and nucleic acids. These four types of macromolecules are essential for life as they serve crucial roles in various cellular processes. Carbohydrates are the primary energy source for cells and provide structural support. Lipids function as energy storage molecules and are essential components of cell membranes. Proteins have diverse functions in cellular processes, acting as enzymes, structural components, and more. Nucleic acids, like DNA and RNA, carry genetic information and are crucial for protein synthesis. Choices B, C, and D are incorrect because they include elements like fats, vitamins, minerals, and hormones, which are not the main types of macromolecules essential for life.

5. Which of the following properties is NOT characteristic of a covalent bond?

• A. Sharing of electrons between atoms
• B. High melting and boiling points
• C. Low electrical conductivity in solid state
• D. Directional bonding

Correct answer: B

Rationale: Covalent bonds are formed by the sharing of electrons between atoms, leading to the formation of molecules with directional bonding. This means that the atoms are held together in a specific orientation. Covalent compounds generally exhibit low melting and boiling points compared to ionic compounds due to the weaker intermolecular forces present in covalent compounds. Furthermore, covalent compounds do not conduct electricity in the solid state because the electrons are localized between the atoms and are not free to move and carry charge. Hence, high melting and boiling points are not characteristic of covalent bonds. The correct answer is 'B' because high melting and boiling points are typically associated with ionic compounds due to their strong electrostatic interactions, while covalent compounds have lower melting and boiling points. Choices A, C, and D are all characteristics of covalent bonds, making them incorrect answers for this question.

Similar Questions