Answer:
I think the awnser is D. Hope it helps
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.
Question: Which pituitary hormone causes liver cells to release somatomedins that increase the rate of uptake of amino acids by cells such as skeletal muscle fibers?
follicle-stimulating hormone
prolactin
thyroid-stimulating hormone
growth hormone
Answer:
growth hormone
Explanation:
Somatomedins are growth factors. The growth hormone makes the cells such as liver cells, skeletal muscles, bones, etc. to secrete the somatomedins. The somatomedins from the liver enter the bloodstream to reach the target cells. The somatomedins make the skeletal muscles, bones, etc. to absorb amino acids into the cells so as to facilitate protein synthesis. This growth factor also downregulates the breakdown of proteins. This is how growth hormone triggers the growth of muscles and soft tissues.
Seafloor spreading occurs at divergent plate boundaries. As tectonic plates slowly move away from each other, heat from the mantle's convection currents makes the crust more plastic and less dense. The less-dense material rises, often forming a mountain or elevated area of the seafloor.
