Integration of Body Systems · Paper 2 — Free Biology SL Practice Questions

A patient is admitted to hospital with severe dehydration following prolonged vomiting and diarrhoea. Blood analysis reveals that the sodium ion concentration in the plasma has risen from the normal range of $135$–$145\,\text{mmol dm}^{-3}$ to $158\,\text{mmol dm}^{-3}$. The patient's urine output is very low and has a high osmolality.

A medical researcher investigates autonomic dysreflexia in a patient with a complete spinal cord transection at the T6 level. The researcher stimulates the patient's skin below the injury site and records the following

A researcher investigates the regulation of blood glucose concentration during moderate-intensity exercise. A healthy volunteer cycles at $70\%$ of maximal oxygen uptake for 30 minutes. Blood samples are taken at rest ($0\,\text{min}$), during exercise ($15\,\text{min}$), and after recovery ($45\,\text{min}$). Variable — $0\,\text{min}$ — $15\,\text{min}$ — $45\,\text{min}$ Plasma glucose $(\text{mmol}\,\text{L}^{-1})$ — $5.0$ — $5.8$ — $5.2$ Plasma insulin $(\mu\text{U}\,\text{mL}^{-1})$ — $12$ — $6$ — $10$ Plasma glucagon $(\text{pg}\,\text{mL}^{-1})$ — $80$ — $140$ — $90$ Plasma adrenaline $(\text{nmol}\,\text{L}^{-1})$ — $0.3$ — $2.5$ — $0.4$ The pancreas contains alpha cells (secrete glucagon) and beta cells (secrete insulin). The sympathetic nervous system innervates the pancreas via splanchnic nerves.