Answer:
Ralph is looking at a vein (likely a muscular vein).
Explanation:
Of all three great types of vessel present in vertebrates (arterial, venous, lymphatic), only veins and lymphatic vessels may normally contain valves. This is an essential feature of vessels which present low pressure flow, since it ensures that such flow is unidirectional.
Since blood cells are not typically found in lymphatic vessels, the vessel in question can be assumed to be a vein.
Sample Response: The main reason for the decrease in trillium is the large number of deer in the forest that are eating the trillium. The author cites a research study performed by scientists as evidence to support her claim. In this study, researchers planted two fields, each containing garlic mustard and trillium. One was left open to deer, and the other was fenced off. Scientists kept track of the fields for several years. They found that trillium was able to regain much of its original space in the protected field. In the unprotected field, there was still more garlic mustard because the deer ate the trillium. The author also states that similar research studies have been conducted in many forests across the United States, and they all reveal similar results.
At this point in time, we have yet to reach the carrying capacity for humans. So yes there is a carrying capacity for humans we just haven't reach it yet.
Due to the ionic bonding of the molecules that allow for the geometric/crystalline structure.
