Module 2, 2.2B Elements Lab

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Elements lab Report

Purpose:

To classify elements based on their properties.

Hypothesis:

None needed for this investigation.

Materials:

Five different elements that you can observe online or in person.

(You may check your periodic table for ideas).

Procedure:

Step 1.

Elements Symbol Colour State Metal, nonmetal or metalloid Conductivity Magnetic
Carbon C Black Solid Non-metal No No
Mercury Hg Silvery white Liquid at room temp. Metal Yes No
Neodymium Nd Silver grey Solid Metal Yes Yes
Silicon Si Reflective with bluish-tinged face Solid Metalloid No No
Helium He Colorless Gas Non-metal Yes No
Bromine Br Reddish Brown Liquid at room temp. Non-metal No No

Questions:

1.   Metals: Hg, Nd/Non-metal: He, Br, C/Metalloid: Si

2.   Hg, Nd, and He

3.   a) Solids at room temp – Exception: Mercury

b) Silver grey – Exception: Gold, Copper

c) Shiny – Metallic luster

4.  a) Found in all states (solid, liquid, gas)

b) Different colors

c) Without metallic luster

Conclusion:

In this experiment, I learnt that helium is actually a great conductor, and that is actually not a conductor at all (I thought it was a semiconductor). I also learnt the different colors, states, symbols, and magnetism of each element. In the future I would like to perform the same experiment but on a larger scale and with more or all the elements.

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How to Build a Telescope

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In its essence, a telescope is an instrument that makes a far away object look closer. To do this, a telescope has a device that collects light from a distant object (objective lens or primary mirror) and brings that light (image) to a focus where a second device (eyepiece lens) magnifies the image and brings it to your eye. To make a simple telescope at home, you will need the following:

  • Two magnifying glasses – perhaps 1 – 1.5 inches (2.5-3 cm) diameter (it works best if one is larger than the other)
  • A cardboard tube – paper towel roll or gift-wrapping paper roll (it helps if it is long)
  • Duct tape
  • Scissors
  • A ruler, yard stick, or tape measure
  • Sheet of printed paper – newspaper or magazine will do

INSTRUCTIONS:

  1. Get the two magnifying glasses and a sheet of printed-paper.
  2. Hold one magnifying glass (the bigger one) between you and the paper. The image of the print will look blurry.
  3. Place the second magnifying glass between your eye and the first magnifying glass.
  4. Move the second glass forward or backward until the print comes into sharp focus. You will notice that the print appears larger and upside down.
  5. Have a friend measure the distance between the two magnifying glasses and write the distance down.
  6. Cut a slot in the cardboard tube near the front opening about an inch (2.5 cm) away. Do not cut all the way through the tube. The slot should be able to hold the large magnifying glass.
  7. Cut a second slot

In the tube the same distance from the first slot as your friend wrote down. This is where the second magnifying glass will go.

  1. Place the two magnifying glasses in their slots (big one at front, little one at back) and tape them in with the duct tape
  2. Leave about 0.5 – 1 inch (1 – 2 cm) of tube behind the small magnifying glass and cut off any excess tube remaining

Sheep Eye Disection

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Purpose: The purpose of my experiment is to compare the Cow eye with the human eye and see the similarities and differences.

Hypothesis: If I see the structures of the cow’s eye, then I would be able to observe how the human eye functions.

Materials:

  • Preserved sheep eye
  • Scissors
  • Prod
  • Dissection tray
  • Protective gloves
  • Paper towel
  • Plastic disposal bag
  • Wear protective gloves. Follow your teacher’s instructions to take them on and off.

Procedure:

  1. 1. Examine the eye before any action.
  2. 2. Use scissors to cut off the muscles and fat.
  3. 3. When you have taken most of the protective fat off the eye that covers the sclera and around the eye you should then have a round and ball like eye.
  4. 4. Then you poke a hole through the sclera so that you may be able to cut the eye in half with scissors.
  5. 5. Cut all the way around the eye. Try not to harm anything inside while cutting.
  6. 6. After you cut, separate the two parts of the eye apart.
  7. 7. Use the prod again and make a hole between the sclera and the cornea.
  8. 8. Use the scissors and cut around the cornea and remove it.
  9. 9. Take out the lenses and clear it from the jelly substance.

10. Put all the pieces of the eye in a disposal bag and clean up your work space and your hands.

Observations: I saw that the retina, where pictures are made into electrical signals and sent to the brain. I also saw the optic nerve which send the electrical signals to the brain. The lens was yellow and less flexible because it was old. This proves that as people age their lens decreases in flexibility.

Questions:

1. A: Sheep have an oval shape pupil, and the humans have a circular one.

B: Sheep have 4 muscles to move their eyes up, down, left, and right. But we have six       muscles so that we can roll our eyes.

C: The cow’s eye is much tougher than the human’s eye.

D: The cow’s eye is always one colour

2. 

3. Because the eye’s lens was old, it was hard, solid (not too much), and yellow. It was a little like an oval shape. I tried to see through it but it was too old.

Conclusions:

–       In the cow’s eye, under the cornea, you would find the iris which is an oval shape. But in the human’s eye, the iris is circular. This shows that our eye accepts more light because the more circular the eye is, the more it lets light enter.

–       I found a jelly-like substance between the cornea and the pupil. I remembered that it helps the cornea stay in great shape.

–       I think my results were accurate because I did figure out facts about the human eye while observing the cow eye.

–       I think my observations were important because when I saw the shapes, sizes and colors, I understood more about the eye and why it functions in the certain way.


Observing onion cells

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Purpose:

My goal is to learn more about staining and to compare between a stained slide and a non-stained slide.

Hypothesis:

If I use staining I would be able to see the cells and organisms better. It will be focused more on the cell and would not be too bright to see.

Materials:

  • Microscope
  • Prepared microscope slides
  • Cover slips
  • Lens paper
  • Tweezers
  • Medicine dropper
  • Water
  • Onion
  • Iodine solution
  • Paper towel

Procedure:

  1. 1. Gather all materials you need to do your experiment.
  2. 2. Use some tweezers to get the skin of the onion when you cut it in half.
  3. 3. Use a medicine dropper to drop a little water on the slide.
  4. 4. Place your onion skin on the drop of water.
  5. 5. Place a cover slip on top of the onion skin.
  6. 6. Now place the slide between the clips and the stage.
  7. 7. Observe and adjust with the course and fine adjustment knob, to get an accurate picture.
  8. 8. When you have pictured it, take the slide off the stage and wait for the next step.
  9. 9. Now use iodine solution to stain the slide. Place a paper towel on one side of the slide and iodine on the other.

10. When you have stained the cell, Place it again on the stage and adjust.

11. Compare between the non-stained and the stained onion skin.

12. Draw the onion cell as a diagram on a separate piece of paper.

13. Clean up all the materials you used and return them to your instructor.

Observations:

When I put the slide without the stain it was harder for me to figure out the difference between the cell and the background.

Questions:

  1. 1. The most difficult part was when I had to flatten the onion so that there would be no bubbles.
  2. 2. The nucleus was less clear without the stain because it was too bright. But when I put the stain it became clearer.
  3. 3. Because when we water a plant, the water goes to the vacuoles and holds it up. But when it tilts that means the plant is lacking water.

Conclusions:

I saw the nucleus only when it wasn’t stained. But when I got it stained I even saw the ribosome and some other organelles. My results were accurate and I learnt to try staining the slide whenever I can to see the cell and other things better on the microscope. I

How do you interpret your observations?

I think that when there is stain around the cell, then our eye can focus more on the brighter side of the slide. This staining make a difference which allows us to see the cell better.


 

Binary fission – The Amoeba

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Amoebae are single-celled, crawling organisms often found in ponds. They have no definite shape and consist of flowing cytoplasm encased in a very flexible cell membrane. Amoebae have organelles (including one or more nuclei) and a contractile vacuole.

 

  1. Movement
  2. Amoebae move when cytoplasm flows out into a long extension of the cell; this crawling, flowing motion is called psuedopodia.
  3. Habitat
  4. Most amoebae live in pond water, moist soil or the ocean; some species are parasitic, living inside the body of another organism.
  5. Diet
  6. Amoebae ingest food through phagocytosis (the process whereby a cell engulfs a piece of food and ingests it). Basically tiny predators, they feed mainly on other microorganisms.
  7. Osmoregulation
  8. Amoebae that live in freshwater ponds must deal with water constantly rushing into the cell. Organelles called contractile vacuoles constantly fill with excess water, and pump it out of the cell. Without a contractile vacuole, the amoeba would explode in a freshwater environment.
  9. Size
  10. Although they are fairly large cells, most amoebas are too small to see with the naked eye; however, some species grow to grape size.

REPRODUCTION:
Binary Fission in amoeba:
Most single celled organisms use the method of binary fission for cell division and reproduction. These include paramoecium, bacterium, and finally amoeba. In this paragraph we will be focusing on amoeba’s cell division which is also its method of reproduction. In binary fission the amoeba consists of one parent which forms the 2 daughter cells. First, the amoeba cell undergoes nuclear division and replicates into two nuclei. The two nuclei divide and move to opposite directions in the parent cell. The cell then produces protiens and nutrients in preperation for binary fission. In the stage of binary fission, the cell divides and forms 2 daughter cells. This process generally occurs when environmental conditions are most favourable. That is, when there is enough food, water, and a favourable temperature.

Bibliography:

http://en.wikipedia.org/wiki/Fission_(biology)

http://www.scienceclarified.com/Al-As/Amoeba.html

http://www.enchantedlearning.com/paint/subjects/protists/amoeba.shtml