Hecker

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1a. The oval green bodies, or the chloroplasts, do appear and are in fact moving in the cytoplasm. 1b. In each individual cell the chloroplasts move in the same direction almost like they are following each other, but in other cells the chloroplasts may not be moving the same as each cell. All chloroplasts no matter what cell seem to be moving at the same speed. 1c. The chloroplasts do have structures for locomotion. No they do not! the sunlight excites them and they move.

2a. The cells seem to be quite large with many bubble shaped objects (starch grains) in them. 2b. The potato cells did not have chloroplasts.

2c. The iodine is a reddish-brown color when leaving the bottle but turns the potato cells black. 2d. There is starch in the potato cells located in the cytoplam in the form of starch grains. 2e. There are no chloroplasts in the potato, or you at least can not see them because potatoes grow in the ground and has no light source.

3a. The onion plant cells do not react the same way that the potato cells do when in comtact with iodine. 3b. Like the potatoes and my hypothesis above (2e) there are no chloroplasts in the onion because it is also grown in the ground with no light source and no photosynthesis.

4a. The tomato skin is several cells thick, not just one. 4b.The tomato skin cells are all different sizes and shapes, but all of them are polgons that seem to have at least 4 to 6 distinct sides. 4c. The cells seem to have red and slight purple color pigments. 4d. The tomatoes plastids are callec chromoplasts. 4e. The cell wall is very defined and thick.

5a. The cells are translucent in color. 5b. This cell seems to be ovular in shape. 5c. The tomato pulp cell wells compared to the tomato skin cell walls are very thin. 5d. The tomato skin cell walls are thicked than the tomato pul cell walls because the tomato skin needs to be much stronger than the tomato pulp. 5e. The tomato pulps chloroplasts are bunched in a group and there are very little compared to the tomato skin. 5f. The tomato skins chromoplasts are very spread out through a cell making it the red it is and although the tomato pulp has much less chromoplasts in a cell compared to the skin the pulp is layer upon layer of cells making the light red color of the pulp.

6a. The cell wall is circular anf thin in some places while thick in others. 6b. The pigments are present and make the cells purple. 6c. The pigments seem to be dispersed throughout the cytoplasm. 6d. This could be the same pigment found in the tomato but I think the tomato is more red and the beet is more purple.

7a. The cheek cells do not possess a wall but they do have a cell membrane. 7b. None of the cells have the same shape or are the same. Each cell appears different. 7c. Each cell possess a vacuole and a visable nucleus.

Conclusioons 1. Both plant cells and animal cells have a nucleus, cell membrane, vacuole and cytoplasm. 2. The main structural differences in plant cells and animal cells is only plants have a cell wall keeping a stronger appearence. 3. The shape of a cell, the chloroplasts and the location of pigments are things that cells taken from a specific area or stucture in an organism that are similar. 4. The purpose of staining cells with iodine in this lab is to prove if starch is present (like in the potato) or to make a clearer view of the cells (such as in the human cheek cells). teacher note : Your photos are very good. The labels are great. You should check your spelling! Chloroplast do not have structures for locomotion. 92%