Answer:
Sinkholes can occur when<u> excessive water use lowers a water table and weakens the substrate.</u>
Explanation:
There are various causes for sinkholes, but all are related to water and how this can affect the soil. One of the causes of sinkholes is the excessive use of water. Excessive use lowers the volume of water in aquifers. As a consequence, the substrates that are above the aquifer change. They can not support large amounts of weight, leading to a sinkhole and soil with low permeability.
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
<em />
<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:
d
Explanation:
prokareyote or bacteria does not have a nucleus.
