Nokea
Which of the following organelles is responsible for protein production in the cell?
- A. Ribosomes
- B. Golgi apparatus
- C. Mitochondria
- D. Lysosomes
Correct Answer: A
Rationale: The correct answer is A: Ribosomes. Ribosomes are the organelles responsible for protein synthesis in the cell. They can be found either freely floating in the cytoplasm or attached to the endoplasmic reticulum. The Golgi apparatus (Choice B) is involved in processing and packaging proteins, not protein production. Mitochondria (Choice C) are responsible for energy production, not protein synthesis. Lysosomes (Choice D) are involved in digestion and waste removal, not protein production.
You may also like to solve these questions
Which of the following is an example of a nonpolar solvent?
- A. Water
- B. Ethanol
- C. Acetone
- D. Hydrochloric acid
Correct Answer: B
Rationale: - Water (option A) is a polar solvent due to its uneven distribution of charge, with the oxygen atom being partially negative and the hydrogen atoms being partially positive.
- Ethanol (option B) is a nonpolar solvent because it has a symmetrical molecular structure that does not result in significant charge separation.
- Acetone (option C) is a polar solvent as it contains a carbonyl group that results in a partial negative charge on the oxygen atom.
- Hydrochloric acid (option D) is a polar solvent due to the presence of the highly electronegative chlorine atom, which results in a partial negative charge.
Which property of matter measures the amount of space occupied by an object?
- A. Mass
- B. Density
- C. Weight
- D. Volume
Correct Answer: D
Rationale: Volume is the property of matter that measures the amount of space occupied by an object. Mass refers to the amount of matter in an object, weight is the force of gravity acting on an object, and density is the mass of an object per unit volume. Volume specifically quantifies the space occupied by an object, making it the correct answer in this context.
What is the largest part of the brain and is responsible for higher functions like thinking, memory, and learning?
- A. Brainstem
- B. Cerebellum
- C. Cerebrum
- D. Thalamus
Correct Answer: C
Rationale: The cerebrum is the correct answer. It is the largest part of the brain and is responsible for higher functions like thinking, memory, and learning. The brainstem (option A) is responsible for basic life functions such as breathing and heart rate, not higher cognitive functions. The cerebellum (option B) is responsible for coordination and balance, not higher cognitive functions. The thalamus (option D) acts as a relay station for sensory information, but it is not the largest part of the brain nor responsible for higher cognitive functions.
What energy transformation occurs when a guitar string vibrates to produce sound?
- A. Mechanical energy to thermal energy
- B. Kinetic energy to potential energy
- C. Electrical energy to sound energy
- D. Potential energy to kinetic energy
Correct Answer: D
Rationale: The correct answer is D. When a guitar string vibrates to produce sound, the energy transformation that occurs is from potential energy (stored energy in the string when it is stretched) to kinetic energy (energy of motion as the string vibrates back and forth). As the string vibrates, its kinetic energy is transferred to the surrounding air molecules, producing sound energy. Choices A, B, and C are incorrect. Choice A, mechanical energy to thermal energy, does not align with the energy transformation involved in producing sound from a vibrating guitar string. Choice B, kinetic energy to potential energy, is the opposite of what happens when a guitar string vibrates. Choice C, electrical energy to sound energy, is not relevant to the energy conversion process in this scenario.
When calcium chloride (CaCl2) dissolves in water, it separates into its ions (Ca2+ and Cl-). This is an example of:
- A. Chemical change
- B. Physical change
- C. Precipitation
- D. Neutralization
Correct Answer: B
Rationale: When calcium chloride dissolves in water, it separates into its ions without forming a new substance, which is characteristic of a physical change. A physical change involves alterations in the substance's physical properties without changing its chemical composition. In this scenario, the chemical formula of calcium chloride remains unchanged, and only its physical state changes by creating ions in the solution. Therefore, the dissolution of calcium chloride in water is an example of a physical change. Choice A, 'Chemical change,' is incorrect because no new substances are formed during the dissolution process. Choice C, 'Precipitation,' is incorrect as precipitation involves the formation of an insoluble solid when two solutions react. Choice D, 'Neutralization,' is incorrect as it refers to a reaction between an acid and a base to form salt and water, which is not the case in the given scenario.