Bacteria In Our School

This week we'll be investigating what types of bacteria grow in our school and where the most bacteria can be found. You conducted an investigation of where students are more likely to contract an illness from bacteria exposure.

While you wait for your cultures to grow, do the following:


Check out the links on the right side of this page. Go to the Bacteria Museum first.

1. What are bacteria?
2. How do bacteria reproduce?
3. How do bacteria evolve?
4. What are the main types of bacteria (shape)?
5. What are some of the benefits and risks of bacteria?

Bacteria is everywhere. Some bacteria can cause illness in people. Can you think of places in the school where there would be harmful bacteria?

Go to the MRSA website.

6. What is MRSA?
7. How do bacteria become drug resistant? Why is this an important evolutionary adaptation?
8. Do you have anti-microbial soap at home? Does it really work? Is it a good idea to have so many anti microbrial products in our homes?

DESIGN AN INVESTIGATION FOR #8

Biology Students Visit Gonzaga University and WSU

The 10th Grade Biology class recently visited Gonzaga University and the Washington State University Health and Sciences Center in Spokane. While at Gonzaga, they particpated in a lab comparing muscle proteins in 4 different animals. The proteins were identified using a process called gel electrophoresis. Proteins are molecules of varying sizes. An electric charge is sent through a gel where samples of the proteins have been placed. The molecules move through the gel with the electric current. The smaller the molecule, the quicker and further it moves through the gel. A standard sample of known proteins is also placed in the gel for comparison. This technology is used for DNA sequencing, studying genetic mutations, evolutionary changes among organisms and has revolutionized modern medicine and science.

After the lab, the students visited the Health and Science Center at the WSU Spokane campus. They got a tour of the building and learned about the different health and science degree programs offered in Spokane as well as what the salaries for those positions are. The highlight of the visit, was a short video on WSU's cadaver lab.

The students were invited back to WSU for a DNA lab. We'll be returning in May.

Intro To e Science Notebooks

Every student in science now has their own blog page and pbwiki page. These two pages will be used as an electronic science notebook. Paper may be used in class for taking notes, but all final work will be submitted electronically.



Click Here to access your blog and wiki page. (The wiki page is set to private, only students and the teacher can see the content).

For help uploading and viewing assignments click here.

Chemistry of Basketball

A good game of basketball is all about chemistry. The ball, the court, the backboard, uniforms and of course the shoes are all made of long chain molecules called polymers. Even your DNA is a polymer. Any molecule that has a repeating sequence of smaller molecules is called a polymer. Some are natural, like the starches in an apple or grain of rice. Others are man made, like theromplastic polyurethane. Thermoplastic poly what? Thermoplastic polyurethane or TPU is a polymer that is extremely elastic and is used to make the bladder in a basketball, and the cushioning in shoes. A slightly similar molecule is used to provide shock absorption in the floor on the court.

Some polymers are unique in thier physical properties because they act like a liquid and a solid interchangeably. These substances are called Non-Newtonian substances. They can be poured like a liquid and take the shape of the container they are put in just like a liquid, but they shatter under extreme force and can hold certain shapes outside of a container.

Non-Newtonian polymers are made from 2 or more polymer chains linked together. For example, in the experiment below, you'll mix glue, which has polyvinyl alcohol(PVA) polymers suspended in water, with borax, which contains another polymer that sticks to the polyvinyl alcohol. Where every the borax connects to the PVA, you get cross linked polymers. The physical properties of this new substance are very different than the original substances.

Experimenting with Polymers

POLYMER 1

Cornstarch Plastic.
1. Place 2 tablespoons of cornstarch in a re-sealable plastic bag.
2. Add 2 tablespoons of water.
3. Add 4-5 drops of corn or other vegetable oil.
4. For additional effect you may add 2-3 drops of food coloring.
5. Zip the bag closed and knead the bag for several minutes to mix.

6. Conduct the polymer tests
7. Unzip a small opening in the top (to vent) and place in a microwave oven on high for 30-40 seconds.
8. Remove the bag and open as soon as it is cool to the touch.
8. Roll into a ball, and try the polymer tests again.

POLYMER 2

Gloob

1 - Use a ruler to make a mark that is 1 cm from the bottom of a small cup.
2 - Pour white glue into your cup until you reach the 1 cm mark.
3. Add 2 drops of food coloring to the glue. Use a clean graduated cylinder to measure out 7 ml of water and add it to the glue. Mix well.
4 – Use a clean graduated cylinder to measure out 8 ml of borax solution. Add it to the glue mixture and stir.
5 - Once the polymer is formed, remove it from the cup and knead it with your hands for several minutes. It should start to form a nice blob after a few minutes.
6 – Complete the polymer tests and type your answers in the comment box at the bottom of this post.
7 - Use a dry paper towel to wipe out your cup and clean your hands. Save the cup for the next slime.

Polymer Tests
Record your observations in the comment box below. Remember to include your name.
Description – What does your polymer look like, feel, smell (waft), etc.?

Slime Rating – Rate it from 1 = not very slimy to 5 = very slimy

Slow Poke Test – Roll the polymer into a ball and slowly poke your finger into it. What happens?

Quick Poke Test – Roll the polymer into a ball and quickly poke it with your finger. What happens?

Slow Pull Test – Roll the polymer into a ball and slowly pull on the ends with your fingers. What happens? Write your observations on your worksheet.

Quick Pull Test - Roll the polymer into a ball and slowly pull on the ends with your fingers. What happens? Write your observations on your worksheet.

Blob Test – Grab a timer. Roll your polymer into a ball and sit it on your plate or the table. How long does it take for it to flatten out?

Hang Test - Grab a timer and a ruler. Roll your polymer into a ball and hold it at a height of 30 cm above the table. Time how long it takes for it to reach the table.

Bounce Test - Roll your polymer into a ball and drop from a height of 30 cm above the table. What happens?

Muscling Our Way to State!!!

Playing basketball requires the coordination and well tuned contraction of millions of muscle cells. These cells allow our bodies to move. Our muscles are made up of 2 different types of fibers: slow-twitch and fast-twitch. Slow-twitch fibers are those that contract gradually. They generate little power, but have high aerobic capacity. This makes them resist fatigue. These are the fibers your body uses for endurance. Fast-twitch fibers contract more quickly and generate more power. These fibers tire quickly though, making them suitable for short bursts of energy. Both types of muscle are needed for basketball. Muscles contract two different ways. Isotonic contractions result in the shortening of of the muscle fibers (lift an object with your arm, your bicep muscle shortens, allowing your arm to bend). Isometric contractions occur when the muscle fibers try to contract but can't because the object is extremely heavy and the muscle can not produce enough force to lift the object.

Do you have more slow-twitch or fast-twitch muscle in your quadriceps (upper legs)?

Experiment
1. Move to an area where each student can have a section of wall to lean against.
Stand with your back against the wall. With the back still touching the wall, slowly lower down into a seated position. At this point, your thighs should be parallel to the ground and your back should be flat against the
wall.
2. Keep track of how long you can sit like this. Try to hold the position as long as possible, but stop when you cannot tolerate the burning sensation that is felt in the upper legs.

Compare your time to the standards below to see how your quadricapes measure up.

Less than 30 seconds: you probably have more fast-twitch muscle fibers in your upper legs.
More than 30 seconds but less than 1 minute: Your upper leg muscles are probably around 50% slow-twitch muscle fibers. The closer to 1 minute, the closer the percentage is to 50%.
More than 1 minute: Your upper leg muscles consist primarily of slow-twitch muscle fibers.

Questions: Post your answers as comments.
1. Create a data table of all the students and their times. Compare the student athletes to students not involved in sports in the class. Who has greater endurance?
What about different sports? Compare volleyball players to basketball or baseball to basketball. Is there a difference in their endurance?

2. Which is more advantageous overall in basketball? slow-twitch or fast-twitch? Why?

3. List 3 moves or plays in basketball that require fast-twitch muscle to improve performance.

How Muscle Cells Work

Click on the link below and complete the following questions in your notebook.

Muscle Cell Parts and Function
1. List the 9 components of a skeletal muscle cell
2. Which part of the muscle cell is responsible for contraction?
3. Muscle cells need a lot more ATP than other cells. Remember ATP is produced through cellular respiration. Do you think muscle cells have more mitochondria or the same as other cells? Why?

4. What mineral was responsible for triggering the whole contraction process?

5. What food sources are good for this mineral?

6. Soft drinks like Mountain Dew and Pepsi interfere with the absorption of calcium. Why should a basketball player avoid drinking soft drinks on a game day?

7. What types of foods should they eat?