Tutor profile: Dean P.
Subject: Natural Sciences
What are invasive species and why do they harm an ecosystem?
Invasive species are exotic (meaning not native to an area) organisms that have a competitive advantage in a system. This is typically because most invasive species do not have natural predators or have evolved to have a competitive advantage. For example, the Emerald Ash Borer has decimated ash trees because it has no predators. Similarly, the Tree of Heaven is able to grow in even the most compacted soil (literally within sidewalk cracks!) so it can grow and reproduce where other plants cannot. Invasive species harm an ecosystem because they disrupt the system's balance, often displacing vital food sources for other organisms or becoming an unstoppable predator.
What does my professor mean when they say "argument"?
Your professor is talking about the main point, or thesis, of your paper. They say "argument" because, in college writing, its important to include your own ideas about a topic. The argument is essentially what you think framed in terms of a point. Someone can almost always disagree with a portion of what you say, so, it can be argued. Often, you'll back up your thoughts with evidence from many sources, but the argument should be your original analysis or thoughts.
Subject: Agricultural Science
What is a dry lot as it pertains to raising food animals?
A dry lot is a pen or shelter area that contains no grass or mud. That's why we say it's "dry". They are used in a number of animal production situations. For example, sheep are often kept on dry lot to reduce parasite populations. In general, they are used as part of rotational grazing systems to reduce parasites and preserve pasture. While useful, its important for producers to be aware of the nutritional needs of their animals and provide adequate feed when animals are on dry lot.
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