Question

the lines that form the network between the cells are nonliving cell walls composed chiefly of cellulose. the cell wall surrounds the plasma membrane, which encloses the cytoplasm. the central part of many plant cells (which is difficult to observe in living cells) is taken up by a central vacuole that is filled with water and salts. locate the nucleus, which appears as a dense, granulated structure in the translucent cytoplasm. note that in some cells, the nucleus looks circular and seems to be lying in the central part of the cell. in other cells, it seems to be compressed and pushed against the cell wall. 4. explain this apparent discrepancy in the shape and position of the nucleus. 5. does the portion of the onion you are viewing have many chloroplasts (small green orbs)? explain. it doesnt have many chloroplasts. the central vacuole, nucleus, and cell wall are separated from the cytoplasm by membranes, but the membranes are difficult to observe in this preparation. part 2. elodea cells in this study, you will examine cells from the leaf of an aquatic plant called elodea (figure 5b - 3). these cells are green because they have chloroplasts, which contain a pigment called chlorophyll. photosynthesis is the process by which this pigment absorbs light energy and converts it into the chemical energy of organic molecules. place a young leaf from the tip of the plant in a drop of water on a slide and add a coverslip. examine the preparation with the 4x, then the 10x and then the 40x objective. locate the nucleus (it may not be visible), cytoplasm, and cell wall.

Explanation:

1. The shape and position of the nucleus can vary due to cell - to - cell differences in the degree of vacuole development and cell turgor. A large central vacuole can push the nucleus to the side, while in cells with less developed vacuoles, the nucleus may appear more centrally located. Also, differences in cell shape and mechanical pressure within the tissue can affect the nucleus's appearance.
2. The portion of the onion being viewed likely has few chloroplasts because onions are underground storage organs. Chloroplasts are mainly involved in photosynthesis and are found in green, above - ground parts of plants where light is available for photosynthesis. Since the onion part being studied is not exposed to light for photosynthesis, it has little need for chloroplasts.

Answer:

1. The shape and position of the nucleus vary due to vacuole development, cell turgor, cell shape, and mechanical pressure.
2. The onion portion doesn't have many chloroplasts as it is an underground storage organ with little need for photosynthesis - related chloroplasts.