Lab 12 Uninary system

Translator: Joseph Geni Reviewer: Morton Bast Before March, 2011, I was a photographic retoucher based in New York City. We're pale, gray creatures. We hide in dark, windowless rooms, and generally avoid sunlight. We make skinny models skinnier, perfect skin more perfect, and the impossible possible, and we get criticized in the press all the time, but some of us are actually talented artists with years of experience and a real appreciation for images and photography. On March 11, 2011, I watched from home, as the rest of the world did, as the tragic events unfolded in Japan. Soon after, an organization I volunteer with, All Hands Volunteers, were on the ground, within days, working as part of the response efforts. I, along with hundreds of other volunteers, knew we couldn't just sit at home, so I decided to join them for three weeks. On May the 13th, I made my way to the town of Ōfunato. It's a small fishing town in Iwate Prefecture, about 50,000 people, one of the first that was hit by the wave. The waters here have been recorded at reaching over 24 meters in height, and traveled over two miles inland. As you can imagine, the town had been devastated. We pulled debris from canals and ditches. We cleaned schools. We de-mudded and gutted homes ready for renovation and rehabilitation. We cleared tons and tons of stinking, rotting fish carcasses from the local fish processing plant. We got dirty, and we loved it. For weeks, all the volunteers and locals alike had been finding similar things. They'd been finding photos and photo albums and cameras and SD cards. And everyone was doing the same. They were collecting them up, and handing them in to various places around the different towns for safekeeping. Now, it wasn't until this point that I realized that these photos were such a huge part of the personal loss these people had felt. As they had run from the wave, and for their lives, absolutely everything they had, everything had to be left behind. At the end of my first week there, I found myself helping out in an evacuation center in the town. I was helping clean the onsen, the communal onsen, the huge giant bathtubs. This happened to also be a place in the town where the evacuation center was collecting the photos. This is where people were handing them in, and I was honored that day that they actually trusted me to help them start hand-cleaning them. Now, it was emotional and it was inspiring, and I've always heard about thinking outside the box, but it wasn't until I had actually gotten outside of my box that something happened. As I looked through the photos, there were some were over a hundred years old, some still in the envelope from the processing lab, I couldn't help but think as a retoucher that I could fix that tear and mend that scratch, and I knew hundreds of people who could do the same. So that evening, I just reached out on Facebook and asked a few of them, and by morning the response had been so overwhelming and so positive, I knew we had to give it a go. So we started retouching photos. This was the very first. Not terribly damaged, but where the water had caused that discoloration on the girl's face had to be repaired with such accuracy and delicacy. Otherwise, that little girl isn't going to look like that little girl anymore, and surely that's as tragic as having the photo damaged. (Applause) Over time, more photos came in, thankfully, and more retouchers were needed, and so I reached out again on Facebook and LinkedIn, and within five days, 80 people wanted to help from 12 different countries. Within two weeks, I had 150 people wanting to join in. Within Japan, by July, we'd branched out to the neighboring town of Rikuzentakata, further north to a town called Yamada. Once a week, we would set up our scanning equipment in the temporary photo libraries that had been set up, where people were reclaiming their photos. The older ladies sometimes hadn't seen a scanner before, but within 10 minutes of them finding their lost photo, they could give it to us, have it scanned, uploaded to a cloud server, it would be downloaded by a gaijin, a stranger, somewhere on the other side of the globe, and it'd start being fixed. The time it took, however, to get it back is a completely different story, and it depended obviously on the damage involved. It could take an hour. It could take weeks. It could take months. The kimono in this shot pretty much had to be hand-drawn, or pieced together, picking out the remaining parts of color and detail that the water hadn't damaged. It was very time-consuming. Now, all these photos had been damaged by water, submerged in salt water, covered in bacteria, in sewage, sometimes even in oil, all of which over time is going to continue to damage them, so hand-cleaning them was a huge part of the project. We couldn't retouch the photo unless it was cleaned, dry and reclaimed. Now, we were lucky with our hand-cleaning. We had an amazing local woman who guided us. It's very easy to do more damage to those damaged photos. As my team leader Wynne once said, it's like doing a tattoo on someone. You don't get a chance to mess it up. The lady who brought us these photos was lucky, as far as the photos go. She had started hand-cleaning them herself and stopped when she realized she was doing more damage. She also had duplicates. Areas like her husband and her face, which otherwise would have been completely impossible to fix, we could just put them together in one good photo, and remake the whole photo. When she collected the photos from us, she shared a bit of her story with us. Her photos were found by her husband's colleagues at a local fire department in the debris a long way from where the home had once stood, and they'd recognized him. The day of the tsunami, he'd actually been in charge of making sure the tsunami gates were closed. He had to go towards the water as the sirens sounded. Her two little boys, not so little anymore, but her two boys were both at school, separate schools. One of them got caught up in the water. It took her a week to find them all again and find out that they had all survived. The day I gave her the photos also happened to be her youngest son's 14th birthday. For her, despite all of this, those photos were the perfect gift back to him, something he could look at again, something he remembered from before that wasn't still scarred from that day in March when absolutely everything else in his life had changed or been destroyed. After six months in Japan, 1,100 volunteers had passed through All Hands, hundreds of whom had helped us hand-clean over 135,000 photographs, the large majority — (Applause) — a large majority of which did actually find their home again, importantly. Over five hundred volunteers around the globe helped us get 90 families hundreds of photographs back, fully restored and retouched. During this time, we hadn't really spent more than about a thousand dollars in equipment and materials, most of which was printer inks. We take photos constantly. A photo is a reminder of someone or something, a place, a relationship, a loved one. They're our memory-keepers and our histories, the last thing we would grab and the first thing you'd go back to look for. That's all this project was about, about restoring those little bits of humanity, giving someone that connection back. When a photo like this can be returned to someone like this, it makes a huge difference in the lives of the person receiving it. The project's also made a big difference in the lives of the retouchers. For some of them, it's given them a connection to something bigger, giving something back, using their talents on something other than skinny models and perfect skin. I would like to conclude by reading an email I got from one of them, Cindy, the day I finally got back from Japan after six months. "As I worked, I couldn't help but think about the individuals and the stories represented in the images. One in particular, a photo of women of all ages, from grandmother to little girl, gathered around a baby, struck a chord, because a similar photo from my family, my grandmother and mother, myself, and newborn daughter, hangs on our wall. Across the globe, throughout the ages, our basic needs are just the same, aren't they?" Thank you. (Applause) (Applause)

1. Flammable materials, like alcohol, should never be dispensed or used near A. an open door. B. an open flame. C. another student. D. a sink. 2. If a laboratory fire erupts, immediately A. notify your instructor. B. run for the fire extinguisher. C. throw water on the fire. D. open the windows. 3. Approved eye protection devices (such as goggles) are worn in the laboratory A. to avoid eye strain. B. to improve your vision. C. only if you don’t have corrective glasses. D. any time chemicals, heat or glassware are used. 4. If you wear contact lenses in the school laboratory, A. take them out before starting the lab. B. you do not have to wear protective goggles. C. advise your science instructor that you wear contact lenses. D. keep the information to yourself. 5. If you do not understand a direction or part of a lab procedure, you should A. figure it out as you do the lab. B. try several methods until something works. C. ask the instructor before proceeding. D. skip it and go on to the next part. 6. After completing an experiment, all chemical wastes should be A. left at your lab station for the next class. B. disposed of according to your instructor’s directions. C. dumped in the sink. D. taken home. 7. If a lab experiment is not completed, you should A. discuss the issue with your instructor. B. sneak in after school and work alone. C. come in during lunch and finish while eating lunch. D. make up some results. 8. You are heating a substance in a test tube. Always point the open end of the tube A. toward yourself. B. toward your lab partner. C. toward another classmate. D. away from all people. Science Laboratory Safety teSt 9. You are heating a piece of glass and now want to pick it up. You should A. use a rag or paper towels. B. pick up the end that looks cooler. C. use tongs. D. pour cold water on it. 10. You have been injured in the laboratory (cut, burn, etc.). First you should A. visit the school nurse after class. B. see a doctor after school. C. tell the science instructor at once. D. apply first aid yourself. 11. When gathering glassware and equipment for an experiment, you should A. read all directions carefully to know what equipment is necessary. B. examine all glassware to check for chips or cracks. C. clean any glassware that appears dirty. D. All of the above. 12. You want to place a piece of glass tubing into a rubber stopper after the tubing has been fire polished and cooled. This is best done by A. lubricating the tubing with water or glycerin. B. using a towel or cotton gloves for protection. C. twisting the tubing and stopper carefully. D. all of the above. 13. Personal eyeglasses provide as much protection as A. a face shield. B. safety glasses. C. splashproof chemical goggles. D. none of the above. 14. Long hair in the laboratory must be A. cut short. B. held away from the experiment with one hand. C. always neatly groomed. D. tied back or kept entirely out of the way with a hair band, hairpins, or other confining device. 15. In a laboratory, the following should not be worn. A. loose clothing. B. dangling jewelry. C. sandals. D. all of the above. 16. The following footwear is best in the laboratory. A. sandals B. open-toed shoes C. closed-toed shoes D. shoes appropriate for the weather3 © 2017 Flinn Scientific, Inc. All Rights Reserved. 17. Horseplay or practical jokes in the laboratory are A. always against the rules. B. okay. C. not dangerous. D. okay if you are working alone. 18. If a piece of equipment is not working properly, stop, turn it off, and tell A. the custodian. B. your lab partner. C. your best friend in the class. D. the science instructor. 19. If an acid is splashed on your skin, wash at once with A. soap. B. oil. C. weak base. D. plenty of water. 20. When you finish working with chemicals, biological specimens, and other lab substances, always A. treat your hands with skin lotion. B. wash your hands thoroughly with soap and water. C. wipe your hands on a towel. D. wipe your hands on your clothes. True—False T F 22. ■ ■ Hot glass looks the same as cold glass. 23. ■ ■ All chemicals in the lab are to be considered dangerous. 24. ■ ■ Return all unused chemicals to their original containers. 25. ■ ■ Work areas should be kept clean and tidy. 26. ■ ■ Pipets are used to measure and dispense small amounts of liquids. You should draw the liquid into the pipet using your mouth. 27. ■ ■ Laboratory work can be started immediately upon entering the laboratory even if the instructor is not yet present. 28. ■ ■ Never remove chemicals or other equipment from the laboratory. T F 29. ■ ■ Chipped or cracked glassware is okay to use. 30. ■ ■ Read all procedures thoroughly before entering the laboratory. 31. ■ ■ All unauthorized experiments are prohibited. 32. ■ ■ You are allowed to enter the chemical preparation/storage area any time you need to get an item. 33. ■ ■ Laboratory aprons should be worn during all lab activities. 34. ■ ■ It’s okay to pick up broken glass with your bare hands as long as the glass is placed in the trash. 35. ■ ■ Never leave a lit burner unattended. 21. Draw a diagram of your science room and label the locations of the following: ■ Fire Blanket ■ Fire Extinguisher(s) ■ Exits ■ Eyewash Station ■ Emergency Shower ■ Closest Fire Alarm Station ■ Waste Disposal Container(s)4 © 2017 Flinn Scientific, Inc. All Rights Reserved. Name: ________________________________________________ Date: ______________________________________________ 1. Flammable materials, like alcohol, should never be dispensed or used near A. an open door. B. an open flame. C. another student. D. a sink. 2. If a laboratory fire erupts, immediately A. notify your instructor. B. run for the fire extinguisher. C. throw water on the fire. D. open the windows. 3. Approved eye protection devices (such as goggles) are worn in the laboratory A. to avoid eye strain. B. to improve your vision. C. only if you don’t have corrective glasses. D. any time chemicals, heat or glassware are used. 4. If you wear contact lenses in the school laboratory, A. take them out before starting the lab. B. you do not have to wear protective goggles. C. advise your science instructor that you wear contact lenses. D. keep the information to yourself. 5. If you do not understand a direction or part of a lab procedure, you should A. figure it out as you do the lab. B. try several methods until something works. C. ask the instructor before proceeding. D. skip it and go on to the next part. 6. After completing an experiment, all chemical wastes should be A. left at your lab station for the next class. B. disposed of according to your instructor’s directions. C. dumped in the sink. D. taken home. 7. If a lab experiment is not completed, you should A. discuss the issue with your instructor. B. sneak in after school and work alone. C. come in during lunch and finish while eating lunch. D. make up some results. 8. You are heating a substance in a test tube. Always point the open end of the tube A. toward yourself. B. toward your lab partner. C. toward another classmate. D. away from all people. Science Laboratory Safety teSt 9. You are heating a piece of glass and now want to pick it up. You should A. use a rag or paper towels. B. pick up the end that looks cooler. C. use tongs. D. pour cold water on it. 10. You have been injured in the laboratory (cut, burn, etc.). First you should A. visit the school nurse after class. B. see a doctor after school. C. tell the science instructor at once. D. apply first aid yourself. 11. When gathering glassware and equipment for an experiment, you should A. read all directions carefully to know what equipment is necessary. B. examine all glassware to check for chips or cracks. C. clean any glassware that appears dirty. D. All of the above. 12. You want to place a piece of glass tubing into a rubber stopper after the tubing has been fire polished and cooled. This is best done by A. lubricating the tubing with water or glycerin. B. using a towel or cotton gloves for protection. C. twisting the tubing and stopper carefully. D. all of the above. 13. Personal eyeglasses provide as much protection as A. a face shield. B. safety glasses. C. splashproof chemical goggles. D. none of the above. 14. Long hair in the laboratory must be A. cut short. B. held away from the experiment with one hand. C. always neatly groomed. D. tied back or kept entirely out of the way with a hair band, hairpins, or other confining device. 15. In a laboratory, the following should not be worn. A. loose clothing. B. dangling jewelry. C. sandals. D. all of the above. 16. The following footwear is best in the laboratory. A. sandals B. open-toed shoes C. closed-toed shoes D. shoes appropriate for the weather5 © 2017 Flinn Scientific, Inc. All Rights Reserved. 17. Horseplay or practical jokes in the laboratory are A. always against the rules. B. okay. C. not dangerous. D. okay if you are working alone. 18. If a piece of equipment is not working properly, stop, turn it off, and tell A. the custodian. B. your lab partner. C. your best friend in the class. D. the science instructor. 19. If an acid is splashed on your skin, wash at once with A. soap. B. oil. C. weak base. D. plenty of water. 20. When you finish working with chemicals, biological specimens, and other lab substances, always A. treat your hands with skin lotion. B. wash your hands thoroughly with soap and water. C. wipe your hands on a towel. D. wipe your hands on your clothes. 21. Draw a diagram of your science room and label the locations of the following: ■ Fire Blanket ■ Fire Extinguisher(s) ■ Exits ■ Eyewash Station ■ Emergency Shower ■ Closest Fire Alarm Station ■ Waste Disposal Container(s) True—False T F 22. ■ ■ Hot glass looks the same as cold glass. 23. ■ ■ All chemicals in the lab are to be considered dangerous. 24. ■ ■ Return all unused chemicals to their original containers. 25. ■ ■ Work areas should be kept clean and tidy. 26. ■ ■ Pipets are used to measure and dispense small amounts of liquids. You should draw the liquid into the pipet using your mouth. 27. ■ ■ Laboratory work can be started immediately upon entering the laboratory even if the instructor is not yet present. 28. ■ ■ Never remove chemicals or other equipment from the laboratory. T F 29. ■ ■ Chipped or cracked glassware is okay to use. 30. ■ ■ Read all procedures thoroughly before entering the laboratory. 31. ■ ■ All unauthorized experiments are prohibited. 32. ■ ■ You are allowed to enter the chemical preparation/storage area any time you need to get an item. 33. ■ ■ Laboratory aprons should be worn during all lab activities. 34. ■ ■ It’s okay to pick up broken glass with your bare hands as long as the glass is placed in the trash. 35. ■ ■ Never leave a lit burner unattended.

Unit 12-Lesson 2

Unit 12-Lesson 3

Unit 12-Lesson 1

Revision 11-12

Cell Size Cells differ not only in their shape but also in their size. A few types of cells are large enough to be seen by the unaided human eye. For example, the nerve cells that extend from a giraffe’s spinal cord to its foot can be 2 m (about 6 1/2 ft) long. A human egg cell is about the size of the period at the end of this sentence. Most cells, how- ever, are only 10 to 50 μm in diameter, or about 1/500 the size of the period at the end of this sentence. The size of a cell is limited by the relationship of the cell’s outer surface area to its volume, or its surface area–to-volume ratio. As a cell grows, its volume increases much faster than its surface area does, as shown in Figure 4-5. This trend is important because the materials needed by a cell (such as nutrients and oxygen) and the wastes produced by a cell (such as carbon dioxide) must pass into and out of the cell through its surface. If a cell were to become very large, the volume would increase much more than the surface area. Therefore, the surface area would not allow materials to enter or leave the cell quickly enough to meet the cell’s needs. As a result, most cells are microscopic in size. Comparing Surface Cells Materials microscope, prepared slides of plant (dicot) stem and ani- mal (human) skin, pencil, paper Procedure Examine slides by using medium magnification (100). Observe and draw the sur- face cells of the plant stem and the animal skin. Analysis How do the surface cells of each organism differ from the cells beneath the surface cells? What is the function of the surface cells? Explain how surface cells are suited to their function based on their shape. Quick Lab Small cells can exchange substances more readily than large cells because small objects have a higher surface area–to-volume ratio. FIGURE 4-5 mb06se_csfs02.qxd 5/18/07 10:54 AM Page 73 74 CHAPTER 4 BASIC PARTS OF A CELL Despite the diversity among cells, three basic features are common to all cell types. All cells have an outer boundary, an interior sub- stance, and a control region. Plasma Membrane The cell’s outer boundary, called the plasma membrane (or the cell membrane), covers a cell’s surface and acts as a barrier between the inside and the outside of a cell. All materials enter or exit through the plasma membrane. The surface of a plasma mem- brane is shown in Figure 4-6a. Cytoplasm The region of the cell that is within the plasma membrane and that includes the fluid, the cytoskeleton, and all of the organelles except the nucleus is called the cytoplasm. The part of the cytoplasm that includes molecules and small particles, such as ribosomes, but not membrane-bound organelles is the cytosol. About 20 percent of the cytosol is made up of protein. Control Center Cells carry coded information in the form of DNA for regulating their functions and reproducing themselves. The DNA in some types of cells floats freely inside the cell. Other cells have a mem- brane-bound organelle that contains a cell’s DNA. This membrane- bound structure is called the nucleus. Most of the functions of a eukaryotic cell are controlled by the cell’s nucleus. The nucleus is often the most prominent structure within a eukaryotic cell. It maintains its shape with the help of a protein skeleton called the nuclear matrix. The nucleus of a typical animal cell is shown in Figure 4-6b. Most animal cells have a cell membrane, a nucleus, and a variety of other organelles embedded in a watery substance. The surface of the cell membrane can be seen in (a). The organelles inside the cell are labeled in the diagram (b). FIGURE 4-6 (a) (b) Mitochondrion Microfilaments Lysosome Golgi apparatus Smooth ER Ribosomes Cell membrane Microtubules Rough ER Nuclear pore Nuclear envelope Nucleolus Nucleus Copyright © by Holt, Rinehart and Winston. All rights reserved. Cell wall Ribosome Cell membrane Peptidoglycan Pili Flagellum DNA CELL STRUCTURE AND FUNCTION 75 A prokaryotic cell lacks a membrane- bound nucleus and membrane-bound organelles. Most prokaryotic cells are much smaller than eukaryotic cells are. FIGURE 4-7 A white blood cell (eukaryotic) changes shape as it attacks purple- stained bacterial cells that are much smaller (prokaryotic). FIGURE 4-8 TWO BASIC TYPES OF CELLS Fossil evidence suggests that the earliest cells on Earth were simple cells similar to some present-day bacteria. As cells evolved, they differentiated into two major types: prokaryotes and eukaryotes. Prokaryotes Prokaryotes (proh-KAR-ee-OHTS) are organisms that lack a membrane- bound nucleus and membrane-bound organelles. Although prokaryotic cells lack a nucleus, their genetic information—in the form of DNA—is often concentrated in a part of the cell called the nucleoid. Figure 4-7 shows a typical prokaryotic cell. Prokaryotes are divided into two domains: Bacteria and Archaea (ahr-KEE-uh). The domain Bacteria includes organisms that are similar to the first cellular life-forms. The domain Archaea includes organisms that are thought to be more closely related to eukaryotic cells found in all other kingdoms of life. Eukaryotes Organisms made up of one or more cells that have a nucleus and membrane-bound organelles are called eukaryotes (yoo-KAR-ee-OHTS). Eukaryotic cells also have a variety of subcellular structures called organelles, well-defined, intracellular bodies that perform specific functions for the cell. Many organelles are surrounded by a mem- brane. The organelles carry out cellular processes just as a person’s pancreas, heart, and other organs carry out a person’s life processes. Eukaryotic cells are generally much larger than prokary- otic cells, as seen in Figure 4-8, which shows a white blood cell (eukaryote) destroying tiny bacterial cells (prokaryotes).

Related quizzes

Related quizzes