What is the difference between mass and weight?

Correct Answer: A

Rationale: Mass is the amount of matter in an object and is a scalar quantity, whereas weight is the force of gravity acting on an object and is a vector quantity. Mass remains constant regardless of the location, while weight can vary depending on the strength of gravity at different locations. Answer choice A correctly defines the difference between mass and weight, making it the correct answer. Choice B is incorrect because mass is not a measure of inertia. Choice C is incorrect as mass is typically measured in kilograms, not pounds. Choice D is incorrect as mass is a scalar quantity, and weight is a vector quantity.

Correct Answer: B

Rationale: The 'lock-and-key' model describes the specificity of the interaction between enzymes and their substrates. In this model, the enzyme's active site acts like a lock that can only be opened by the specific substrate molecule, which serves as the key. This specific binding ensures that enzymes catalyze particular reactions and do not interact with other molecules indiscriminately. Protein folding (option A) is the process by which a protein attains its functional three-dimensional structure but is not directly related to the lock-and-key model. Muscle contraction (option C) and blood clotting (option D) are complex biological processes but are not directly associated with the lock-and-key model of enzyme-substrate interaction.

Correct Answer: A

Rationale: In physics, power is defined as the rate at which work is done, which refers to the amount of energy transferred or converted per unit time. Choice B, 'The amount of force applied,' is incorrect as power is related to work done, not just force. Choice C, 'The distance an object travels,' is not the definition of power but rather relates to displacement or distance. Choice D, 'The potential energy of an object,' is not the correct definition of power; potential energy is different from power. Therefore, the correct definition of power in physics is the rate at which work is done.

Correct Answer: B

Rationale: A) Trait: A trait is a characteristic or feature of an organism that is determined by its genes. B) Mutation: A mutation is a permanent alteration in the DNA sequence that can result from errors during DNA replication, exposure to mutagens, or other factors. C) Allele: An allele is a variant form of a gene that can result in different traits or characteristics. D) Variation: Variation refers to the differences in traits or characteristics among individuals of the same species, which can be influenced by genetic and environmental factors. In this context, the term that specifically refers to a permanent alteration in the DNA sequence is "mutation."

Correct Answer: B

Rationale: Energy is the capacity to do work, while power is the rate at which work is done or energy is transferred. Power is the amount of energy transferred or converted per unit time. Therefore, energy is related to power as the rate at which work is done. Choice A is incorrect because power and energy are not the same; they are related concepts but represent different aspects. Choice C is incorrect because power does not refer to stored energy but rather the rate of energy transfer. Choice D is incorrect because energy is not the rate at which power is transferred, but the capacity to do work or cause change.