Self-study
The hormone testosterone protects brain cells from injury and reduces levels of the protein beta-amyloid in the brain. ████████████ ████████ ███████████ ██ ███████████ ████████ ███ ██████ █████ █████ █████ ███ ███████████ ██ ██████ ███ ████████ ████ ███████████ ██ ███████████ ████████ ██ █████ ██ ██████ ██ █████ ████ ████████
Summary
Testosterone protects brain cells from injury. Testosterone reduces levels of beta-amyloid, a protein, in the brain. Beta-amyloid has a causal relationship with Alzheimer’s disease. People whose brain cells are more susceptible to injury are probably more likely to get Alzheimer’s.
Strongly Supported Conclusions
Testosterone protects against Alzheimer’s by reducing the likelihood of brain cell injury. A decline in testosterone increases the risk of Alzheimer’s disease.
5.
Which one of the following ████ █████████ █████████ ███ █████████
a
anyone whose brain █████ ███ ███████████ ██ ██████ ████ ██████████ ███████ ███████████ ███████
This is unsupported because we don’t know that being susceptible to brain cell injury is a sufficient condition for Alzheimer’s disease. We only know that people susceptible to brain cell injury are probably more susceptible to Alzheimer’s disease.
b
whether a person ████████ ███████████ ███████ ██ █████████ ████████ ██ ███ █████ ██ ████████████ ██ ███ ██ ███ █████
This is unsupported because the stimulus leaves open the possibility that other factors besides beta-amyloid influence Alzheimer’s development.
c
Alzheimer's disease leads ██ █ █████████ ██ ████████████ █████
This is unsupported because the causation may be the other way around. Reductions in testosterone may lead to Alzheimer’s disease.
d
only people with ███████████ ███████ ███ ██ ████ ███ ██████ ██ █████ █████
This is unsupported because people susceptible to brain cell injury may have low testosterone with no Alzheimer’s disease.
e
a decline in ████████████ █████ ████ ███ ██ █████████ ████ ███ ███████████ ███████
This is strongly supported because a decline in testosterone leads to increased susceptibility to brain injury, which probably makes someone more likely to develop Alzheimer’s disease.