"A. cutting down most of the trees in a forest to make furniture" is the correct answer because some trees play a vital role in processing the carbon in the air.
Answer:
What is the effect of power/magnification on the frequency and size of organelles under a microscope?
Explanation:
Organelles within the cell are responsible for carrying out various functions. Some cells are more specialized than others, and may have particular organelles at a higher frequency, or showing a variation in size; sub-cellular structures become more visible at higher magnifications under the microscope.
Hypotheses:
- organelle A's frequency decreases while B's frequency increases at higher magnifications
- organelle A's size increases while B's size decreases at higher magnifications
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<em>Dependent variables: size and frequency cell organelles</em>
<em>Independent variable: power/magnification at low (x4), medium(x10) and high (x40)</em>
<em>Controlled variables: Type of organelles, microscope used, cell examined, </em>
Method:
1. Examine the organelles A and B in a cell mounted on a slide; use the fine adjustment to focus on the cell.
- Frequency: What is the average number of organelle A versus B, seen at low (x4), medium (x10) and high (x40) magnifications?
- Size: Measure the average diameter of organelle A versus B using an ocular micrometer at low, medium and high magnification.
2. Record and tabulate observations.
Answer:
Glaciers will only form under certain conditions and in specific environments. A cold climate and sufficient moisture in the air for the precipitation of snow are both necessary factors that permit at least some snow to last year-round. This allows for the build-up and compaction of snow that will eventually become glacial ice. Sufficiently cold climate conditions exist at high altitudes and high latitudes.
Explanation:
There must be landmasses at high latitudes for continental glaciers to occur, as they cannot form over open water. While persistent sea ice can and does form, because it floats, it does not flow as a glacier does.