Name:________________Number:_______ Class group:__________
LABORATORY
1ÂşESO Science- Laboratory activities
Living things – Unit 3
Light Microscope The light microscope is a device that lets us observe tissues and cells. Light microscopes can magnify objects up to 1,000 times. Look carefully at the different parts a microscope is made of and read the definitions below.
Internet resource http://www.skoool.ie/skoool/junior.asp?id=1310 PROPER USE OF THE MICROSCOPE 1. When moving your microscope, always carry it with both hands (Figure 1). 2. Turn the revolving nosepiece so that the lowest power objective lens is "clicked" into position. 3. Place the microscope slide on the stage and fasten it with the stage clips. 4. Using the coarse adjustment, lower the objective lens down as far as it will go without touching the slide! Note: Look at the slide and lens from the side when doing this (see Figure 2). 5. Look through the eyepiece and adjust the illuminator (or mirror) and diaphragm (Figure 3) for the greatest amount of light.
6. Slowly turn the coarse adjustment so that the objective lens goes up (away from the slide). Continue until the image comes into focus. Use the fine adjustment, if available, for fine focusing. 7. Move the microscope slide around so that the image is in the centre of the field of view and readjust the mirror, illuminator or diaphragm for the clearest image. 8. You should be able to change to the next objective lenses with only slight focusing adjustment. Use the fine adjustment, if available. If you cannot focus on your specimen, repeat steps 4 through 7 with the higher power objective lens in place. DO NOT ALLOW THE LENS TO TOUCH THE SLIDE! 9. The proper way to use a monocular microscope is to look through the eyepiece with one eye and keep the other eye open (this helps avoid eye strain). If you have to close one eye
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Name:__________________
Observing Cells Lab Purpose: To observe single cells underneath the compound microscope by looking at onion skin and cheek cell samples. Materials: 1. Compound Microscope 2. Slide 3. Cover Slip
4. Onion 5. Iodine 6. Cotton swabs
Part A- Onion Skin Cells Procedure: 1. Obtain a compound Microscope, slide and cover slip. 2. Watch your teacher peel away the skin of an onion and prepare the slide. 3. Obtain a section of onion from your teacher, peel the skin away and place it on a slide. 4. Put one drop of water, then one drop of iodine on the onion skin and place the cover slip on top. 5. Look at the onion cells at low, medium, and high power. Observations: Draw and label what you see. Low (4x)
Medium (10x)
Name:__________________
High (40x)
Discussion Questions: 1. What was the shape of the onion skin? Why is that important? _____________________________________________________ 2. What organelles were visible? What ones were not? ______________________________________________________ 3. What part of the onion cell did the Iodine Stain? ______________________________________________________
Name:__________________
Part B- Cheek Cells Procedure: 1. Obtain a compound Microscope, slide and cover slip. 2. Watch your teacher take a cheek swab and prepare the slide. 3. Obtain a cotton swab to swab the inside of one partner’s cheek. Rub the swab onto the slide, and immediately throw the swab into the garbage. 4. Place the cover slip on top. 5. Look at the cells at low, medium, and high power. Observations: Draw and label what you see. Low (4x)
Medium (10x)
Name:__________________ High (40x)
Discussion Questions: 3. What was the shape of the cheek cell? Why is that important? _____________________________________________________ 4. What organelles were visible? What ones were not? ______________________________________________________ 3. What were the major differences you could see between the onion cell and the cheek cell? ______________________________________________________
Kingdom Monera Bacteria 3D/ My Great, great realtive Bacteria occur in a wide range of shapes, including spheres, rods and spirals. Explore biology with our interactive 3D animations! Be actively involved in learning about biology by following the latest results of 3D animation.
Harmful Bacteria? There’s an App for That. In developing countries, more than 3.4 million people die each year due to water-related diseases, while the U.S. and Europe routinely face E. coli and salmonella contamination in their food supplies. In response, Ozcan developed the first-of-its-kind microscopy tool that enables public health workers to test for harmful bacteria in the field using only a cell phone http://uctv.tv/shows/Cell-PhoneScience-Saving-Lives-UCTV-Prime-Cuts-24210
1ºESO Science- Laboratory activities
Living things – Unit 3
ORGANISMS WHICH LIVE IN POND WATER
1. Look at pond water under the microscope. 2. Investigate what organisms are present. Use a key to identify them. Which ones are protoctista? How do you know?
3. What have you seen? Draw it or describe
4. List the materials you have used
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1ÂşESO Science- Laboratory activities
Group
Key features
Bacteria
single celled, dots or strands, just visible with strongest magnification, cyanobacteria are larger
Protozoa
single celled, with tiny hairs or pseudopodia
Algae
Rotifers
Gastrotrichs
Worms
Bryozoa
Hydra
Water bears (Tardigrades)
Arthropods
other Arthropods: Insect stages
single celled, mostly green, sometimes yellow-brown
wheel-like, hairy appendages, transparent, free swimming or attached 0.2 - 1 mm two tails, hairy, round mouth opening 0.1 - 0.5 mm
long thin body, many non related forms
plant-like or jelly-like colony, crown of tentacles individuals: 0.25 - 5 mm green brown or colourless, body and tentacles contract and stretch extended: 20 mm 8 stumpy legs, slow moving <1 mm See gallery links on the right for some of the finest video clips on the Web of these cute critters!
jointed limbs; many groups e.g. crustaceans ('water fleas'), mites
wide variety of forms
Living things â&#x20AC;&#x201C; Unit 3
Microscope links Introduction to bacteria Spirochaetes
Go to protozoa overview: e.g. ciliates, amoeba, heliozoa, euglenoids
Go to algae overview: eg. flagellates, diatoms, desmids, filamentous algae
'Smallest page on the web' - rotifers
No Micscape resources. (Articles welcomed!)
Go to worms overview: e.g. flatworms, annelids, nematodes Bryozoans Pond fairies - Plumatella repens Introduction to hydra Hydra in 3D Hydra oligactis Video clips of a hydra
Hunting for 'bears' in the backyard The incredible water bear Water bear video gallery I Water bear video gallery II
Go to arthropods overview: e.g. ostracods, copepods, water fleas, mites etc.
Go to insect stages overview: e.g. caddisfly larvae, dragonfly nymphs, water beetles, etc.
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FUNGI KINGDOM LABORATORY - OBSERVATION OF DIFFERENT FUNGI. Aim Observation of different fungi. Material Bread, mould, mushroom and Binocular lens. Observation a) Bread mould - View without the lens (naked eye) and draw the mould which you see. Draw what you can see and identify hyphae (threads) and spores (dots).
Naked eye:
Binocular lens:
magnification:........
- What kind of cells are fungi made up of? Observation a) Mushroom - View without the lens (naked eye) and draw the mushroom which you see. Use your notes to identify the anatomy of this living thing.