Human Nervous System

The “fight or flight” response is mediated by the sympathetic nervous system and adrenal medulla, which release adrenaline and noradrenaline. This leads to increased heart rate, blood pressure, and alertness, preparing the body to face a threat.

In the CNS, a collection of neuronal cell bodies is referred to as a nucleus, whereas in the PNS, it is called a ganglion. Bundles of axons are called tracts in CNS and nerves in PNS.

Cerebrospinal fluid (CSF) is indeed alkaline and circulates multiple times a day. It helps remove metabolic waste and toxins from the central nervous system, supporting both statements and their logical link.

Alzheimer’s disease indeed affects individuals more commonly after the age of 65. It is characterized by neurodegeneration, resulting in memory loss, confusion, and difficulty with cognitive tasks.

The diencephalon in the frog brain regulates homeostasis, controls body temperature, and integrates autonomic functions. These include the perception of heat, cold, and internal physiological processes.

Astrocytes are star-shaped glial cells in the central nervous system that play a key role in forming the blood-brain barrier. They help maintain the environment around neurons by regulating ion and nutrient transport and limiting the entry of harmful substances.

To find the incorrect match, let’s compare each respiratory volume with its typical value for a healthy adult.
Tidal volume, the air moved during normal breathing, is about 500 mL—option (1) is correct.
Inspiratory Reserve volume, the extra air inhaled beyond tidal volume, is typically 2,500–3,000 mL, so 2,500 mL in option (2) is correct.
Residual volume, the air remaining in the lungs after maximum exhalation, is around 1,200 mL—option (3) is correct.
Expiratory Reserve volume, the additional air exhaled beyond tidal volume, is usually 1,000–1,200 mL, but option (4) lists it as 3,000 mL, which is too high and incorrect.

Final Answer: The incorrect match is Expiratory Reserve volume – 3,000 mL, so the correct option is (4).