I need help with biology questions on cells. please help, it's due tomorrow ):?

Question

i don't know the answer to these questions. but i've dont everything else..

3. When viewing a cell under the microscope how can you tell if it has depth or thickness?
9. Why can’t cheek cells and onion cells carry out photosynthesis?
5. Why do we stain cells when sometimes viewing them?
17. What's the cell theory?

Answer 1

3. Turn the fine adjustment knob up and down slightly to see different levels of the cell. If you see different parts of the cell when you do this, then the cell is not flat.
9. These cells do not have chloroplasts, so they cannot carry out photosynthesis. (They're always in the dark anyway, so photosynthesis wouldn't work.)
5. Staining cells helps cell parts show up that would otherwise be colorless and difficult to see.
17. The cell theory has three parts:
a. The cell is the basic unit or building block of living things.
b. All living things are made of cells.
c. Cells are made by other living cells.

Answer 2

9. cheek cells can not because photosynthesis occurs in the chloroplasts which are not in cheek cells and an onion cell is underground so it sees no light..
5. Stainging cells help to view cells. if u looked at an unstained cheeck cell it would be almost completely transparent.
6. The cell theory says that all things are made from cell, and that all cells are made from other cells and contain energy within them