In contrast to younger patients, older patients are more prone to a decrease in blood pressure (bp) upon standing because

Older patients are more prone to a decrease in blood pressure upon standing because the body is less able to adapt the BP to rapid postural changes.
When a patient standing, some of the blood come to the leg. With less blood, the heart is harder to maintain its pressure.
The body will respond with constricting the vessel or increasing heart muscle power. But in an elderly patient, this response is weaker. Some of the older patients also consume a drug that will disturb this mechanism.

1. true.2. true.3. true.4. false.5. true.the concept of darwin's theory of evolution involves the idea that there are limited resources in a given living environment and that the organisms which live within have variations in their genetic make up due to random mating. the ones with beneficial genetic variations can express certain traits which give them an upper hand in surviving and reproducing in the said environment compared to ones who may have a more disadvantageous variation in traits. over time, the organisms with an upper hand will survive and reproduce more frequently and pass on their beneficial genes while the others die. the result is evolution, where we observe (usually, but not always) eventually, phenotypic distinct changes.

The answer is reflection.