Final answer:
If a tumor secretes high levels of osteoclast-activating factor, it will result in increased osteoclast activity, which causes decreased bone density, increased bone fragility, and higher blood levels of calcium. All of the answers provided in the question are correct.
Step-by-step explanation:
If a tumor secretes high levels of osteoclast-activating factor, several consequences relating to bone metabolism are likely to occur. The secretion of this factor leads to an increase in osteoclast activity. Osteoclasts are cells that break down bone tissue, releasing minerals, including calcium, into the blood. As a result of intensified osteoclast activity, one would observe:
- A decline in bone density due to the accelerated resorption of bone by osteoclasts.
- A subsequent increase in bone fragility, making bones more susceptible to fractures.
- Elevations in blood levels of calcium (hypercalcemia) as the minerals contained within bone are liberated into the bloodstream.
Therefore, all of the provided answers are correct, including increased activity of osteoclasts, decreased bone density, heightened bone fragility, and higher calcium levels in the blood.