Transcript Plant Cells
Cells Functions and Processes Marybeth Gardner FBISD Science specialist 2007 Are these cells? Virus Bacterial Prokaryote Eukaryote Is it a plant or animal cell? What do you look for in a plant and animal cell? Blood cells leaf cells cheek cells Cells Animal Plant cell membrane chloroplast mitochondria nucleus vacuole Cell wall How are animal and plant cells alike? Cell Organelles To Know: Nucleus – the control center Contains most of the cell’s DNA genetic information for coding proteins. It tells the cell how to do its jobs of dividing, making proteins, ETC. Mitochondria - Energy Provides energy for cell use. Converts energy in food to ATP Powerhouse of the cell Chloroplast Converts solar energy into food or chemical energy for plants. Plants are the source of food and energy for organisms that cannot make their own food such as animals, fungi. Vacuole Stores water, minerals and nutrients. vacuole Cell Membrane – “Gate Keeper” • Protects and supports the cell • Cells require a variety of molecules to survive. The cell membrane regulates the materials that enter and leave the cell. Homeostasis, Diffusion, and Osmosis Homeostasis is the maintenance of a stable internal state within an organism. Examples of homeostasis in our bodies are: Regulation of water content Regulation of body temperature Regulation of blood glucose levels Name 3 examples of homeostasis in cells. What do individual cells need to control or regulate? Transportation of molecules in plant cells: Diffusion 6. Explain the process in the beaker on the overhead. Transportation of molecules in plant cells: Diffusion The spontaneous movement of particles from an area of higher concentration to an area of lower concentration. Transportation of molecules in plant cells: Osmosis View the osmosis animation. What does the red line represent? Notice the movement of water before salt is added. Explain the movement of water molecules when salt is added. Notice the level of the water. http://www.stolaf.edu/people/giannini/flashanimat/transport/osmosis.swf Transportation of molecules in plant cells: Osmosis What happens in osmosis? Explain the direction of water movement. http://www.tvdsb.on.ca/westmin/science/sbi3a1/Cells/Osmosis.htm Scroll down to show the 3 animations. Transportation of molecules in plant cells: Osmosis View the following clips on osmosis in plant cells. http://video.google.com/videoplay?docid=7439512663261866598&q=osmosis&hl=en http://video.google.com/videoplay?docid=-1349343891006732106&q=osmosis&hl=e A 10% salt solution was added to the plant cells. What happened to the water in the cell? Evaluation: Osmosis Think about what happens to the skin on your hands and toes after soaking in water or going swimming. (Osmosis) Next slide: Evaluation: answer a or b Osmosis 1. Place your hand in salt water. What happens to the cells of the skin? A. Wrinkled hands B. Smooth hands OR Evaluation: answer a, b, or c Osmosis 2. Cells placed in pure distilled water without any minerals will: A. Remain normal B. C. Evaluation: answer a or b Osmosis Predict what will happen to the cells of the fish. 3. Place a salt water fish from the Gulf of Mexico into an aquarium of fresh water. A. Fish cells swell and burst B. Fish cells lose water and dehydrate OR 4. Describe the transportation of molecules in these slides of onion cells. END OF POWER POINT Transportation of molecules in plant cells: Osmosis You and your partner have two beakers. Add 28 mL tap water to both beakers. Add a teaspoon of salt to one beaker and label it with an “s”. Use the eye-dropper to remove enough water from the beaker with salt until the liquid in both beakers is the same. Transportation of molecules in plant cells: Osmosis Add a carrot or potato to both beakers. 11. Describe the texture and color of the carrot or potato. 12. Which beaker has the greater concentration of water molecules? 13. What is the solute in one of the beakers? Transportation of molecules in plant cells: Osmosis 14. Hypothesize: what do you think will happen to the carrot or potato you put in salt water? What do you think will happen to the one in regular tap water?