Nokea
Which division of the peripheral nervous system is responsible for transmitting signals from the central nervous system to skeletal muscles, enabling voluntary muscle movements?
- A. Somatic nervous system
- B. Autonomic nervous system
- C. Sympathetic nervous system
- D. Parasympathetic nervous system
Correct Answer: A
Rationale: The correct answer is the somatic nervous system. The somatic nervous system is responsible for transmitting signals from the central nervous system to skeletal muscles, allowing for voluntary muscle movements. The autonomic nervous system, sympathetic nervous system, and parasympathetic nervous system are not involved in voluntary muscle movements. Instead, they regulate involuntary functions of the body such as heart rate, digestion, and breathing. Therefore, choices B, C, and D are incorrect as they are not associated with voluntary muscle movements.
You may also like to solve these questions
What are enzymes?
- A. Building blocks of muscle
- B. Biological catalysts
- C. Energy source
- D. Antibodies
Correct Answer: B
Rationale: Enzymes are biological catalysts, not building blocks of muscle. They speed up chemical reactions in living organisms without being consumed in the process. Enzymes are not an energy source or antibodies. They play a crucial role in various biological processes by lowering the activation energy required for a reaction to occur, thereby increasing the rate of the reaction.
Which indicator is commonly used to distinguish between acidic and basic solutions?
- A. Methyl orange
- B. Phenolphthalein
- C. Universal indicator
- D. All of the above are common indicators.
Correct Answer: B
Rationale: Phenolphthalein is commonly used to differentiate between acidic and basic solutions. It changes color, turning pink in basic solutions and remaining colorless in acidic solutions due to a specific pH range. While methyl orange and universal indicator are also indicators used for pH testing, phenolphthalein is especially known for its distinctive color change in response to acidic and basic solutions, making it the correct choice. Methyl orange is typically used in titrations for a sharp color change at a specific pH, and the universal indicator is a mixture of indicators displaying a range of colors depending on the pH value, not specifically tailored to acidic and basic distinctions.
What property of a substance refers to its ability to be drawn into thin wires without breaking?
- A. Malleability
- B. Viscosity
- C. Ductility
- D. Conductivity
Correct Answer: C
Rationale: Ductility is the property that allows a substance to be drawn into thin wires without breaking. Malleability, on the other hand, is the ability to be hammered or rolled into thin sheets. Viscosity is the measure of a fluid's resistance to flow. Conductivity, lastly, refers to a substance's ability to conduct electricity or heat. Therefore, in this context, the correct answer is ductility as it specifically relates to the ability of a substance to be drawn into thin wires without breaking.
Parkinson's disease is a neurodegenerative disorder affecting which neurotransmitter?
- A. Dopamine
- B. Acetylcholine
- C. Serotonin
- D. Glutamate
Correct Answer: A
Rationale: Parkinson's disease is primarily caused by the loss of dopamine-producing neurons in the brain. Dopamine is a neurotransmitter that plays a crucial role in coordinating movement. The reduction of dopamine levels leads to the characteristic motor symptoms of Parkinson's disease, such as tremors, rigidity, and bradykinesia. Choice B, acetylcholine, is involved in functions like muscle contraction and autonomic nervous system regulation but is not primarily affected in Parkinson's disease. Serotonin (Choice C) is involved in mood regulation and sleep, not the main neurotransmitter affected in Parkinson's disease. Glutamate (Choice D) is the major excitatory neurotransmitter in the central nervous system and is not primarily implicated in Parkinson's disease pathophysiology.
What is the energy required to break a chemical bond called?
- A. Kinetic energy
- B. Potential energy
- C. Activation energy
- D. Bond energy
Correct Answer: C
Rationale: Activation energy is the energy required to break a chemical bond and initiate a chemical reaction. It is the minimum amount of energy needed to start a chemical reaction by breaking bonds in the reactant molecules. Kinetic energy (option A) is the energy of motion and is not directly related to breaking chemical bonds. Potential energy (option B) is stored energy that can be converted into other forms of energy but is not specifically about breaking chemical bonds. Bond energy (option D) refers to the energy required to break a particular chemical bond in a molecule and is not the general term for the energy needed to break any chemical bond. Activation energy is crucial in determining the rate of a chemical reaction as it affects the probability of reactant molecules colliding with sufficient energy to surpass the energy barrier and form products.