1. Which structure is responsible for the production of cerebrospinal fluid (CSF)? A. Choroid plexus B. Arachnoid villi C. Pia mater D. Dura mater Answer: A. Choroid plexus Rationale: The choroid plexus is a network of cells that line the ventricles of the brain and produce cerebrospinal fluid, which cushions the brain and spinal cord. 2. The blood-brain barrier (BBB) is impermeable to many substances. Which cell type is primarily responsible for maintaining the BBB? A. Neurons B. Astrocytes C. Oligodendrocytes D. Microglia Answer: B. Astrocytes Rationale: Astrocytes are star-shaped glial cells that contribute to the blood-brain barrier's integrity by regulating the passage of materials from the bloodstream into the brain. 3. Which part of the nervous system controls involuntary actions such as heart rate and digestion? A. Somatic nervous system B. Autonomic nervous system C. Central nervous system D. Peripheral nervous system Answer: B. Autonomic nervous system Rationale: The autonomic nervous system regulates involuntary functions, including heart rate, digestion, respiratory rate, pupillary response, urination, and sexual arousal. 4. Damage to which area of the brain would most likely result in aphasia (loss of ability to understand or express speech)? A. Occipital lobe B. Parietal lobe