Final answer:
Orthostatic hypotension, which is true for the statement, happens due to insufficient blood flow to the brain when standing, causing symptoms like dizziness. Causes include low blood volume or autonomic failure.
Step-by-step explanation:
The statement that orthostatic hypotension is temporary low blood pressure when rising from a reclining or sitting position is true. This condition occurs due to pooling of blood in the lower limbs, which consequently leads to reduced blood flow to the brain when the body's position changes. It is often experienced as a feeling of dizziness or lightheadedness upon standing up. The cardiovascular system must adjust to the new challenge of maintaining blood pressure against gravity when moving to an upright position. If there's inadequate cardiac output from the sympathetic system, a person can experience neurological symptoms like a brief loss of balance or a feeling of 'wooziness'.
There are various causes for orthostatic hypotension, including hypovolemia (low blood volume), which can result from dehydration or the effect of certain medications like diuretics and vasodilators. These medications lower blood pressure to manage systemic hypertension but can also contribute to this condition. Another cause is autonomic failure, found in disorders that affect sympathetic functions, such as diabetes or multiple system atrophy. Addressing an underlying condition, like controlling blood glucose in diabetes, can improve the orthostatic hypotension.