1. Gel electrophoresis separates DNA fragments based on their __________.

2. True or false, larger DNA fragments move faster because the larger pieces can fall faster.

3. What is a proper title for the graph? 4. What type of correlation is shown? 5. Predict the percentage at day 12.

2/5 Daily Catalyst Pg. 14 MRI

Seating Chart

Scientific Discovery Unit #2 test Friday, Feb. 6th

Class points by Thursday 100 points Friday, after test we will watch Walle

Interims on Friday Extra credit

Ecology Unit #3 Next Monday

2/5 Class Business Pg. 14 MRI

Daily Catalyst Class Business Gel Electrophoresis work time MRI notes Writing in Science Review for test

2/5 Agenda Pg. 14 MRI

Directions: With your partner, complete the gel electrophoresis packet. This packet is due TODAY. When you finish, study for the unit test tomorrow with your partner.

Time: 15 minutes Noise: 1 (with partner)

Gel Electrophoresis

Cite examples of scientific advances and emerging technologies and how

they affect society (e.g. MRI, DNA in forensics).

2/5 Objective

In order to solve the grand challenge and assess MRI safety issues, we must learn how the MRI

machine works. We can then combine this knowledge with our knowledge of magnetic fields to

determine safety issues with the MRI. Safety engineers are always looking for points of weakness in order to eliminate any potential safety hazards.

Why are we learning about this?

Key Point #1: MRI Magnetic Resonance Image

A noninvasive imaging technique

Note time

Key Point #2: No radiation is used. magnetic fields and radio waves are used

to scan the body

What’s the difference between x-ray and MRI’s?

MRI is helpful for looking at a person's eyes, ears, heart, and circulation system. It also helps doctors see inside joints, cartilage, ligaments, and tendons.

MRI lets doctors detect problems in the brain, spinal cord, skeleton, chest, lungs, abdomen, pelvis, wrists, hands, ankles, and feet.

It helps doctors identify infections and conditions that cause swelling inside the body.

It allows doctors to see when there isn't a problem inside the body — like a tumor, for example. Doctors call this "ruling out" a condition.

MRI

Fasting is not required, but removing all metal items is.

Key Point #3: No metal items may be worn due to the strong magnetic field.

Last 20-90 minutes depending on the need of each patient.

A radiologist will read your scans and discuss with your doctor your results.

Preparing for a MRI

Overall, MRI’s are safe and effective. With all procedures, there are potential hazards. One potential effect is the tearing of tissues due

to the strong magnetic field.

Side Effects

Most of the human body is made up of water molecules, which consist of hydrogen and oxygen atoms.

Key Point #4: ~70% of body is made of water (H2O) At the center of each hydrogen atom there is an even

smaller particle called a proton. Every hydrogen has a proton in the center

Protons are + charge Protons are like tiny magnets and are very sensitive to

magnetic fields.

How MRI works

When you lie under the powerful scanner magnets, Key Point #5: the protons in your body line up in the

same direction, in the same way that a magnet can pull the needle of a compass.

Short bursts of radio waves are then sent to certain areas of the body, knocking the protons out of alignment. When the radio waves are turned off, the protons realign and in doing so send out radio signals, which are picked up by receivers.

Key Point #6: Radio waves knock the protons out of order. When the radio waves turn off, the protons realign and send a message.

How MRI works

These signals provide information about the exact location of the protons in the body. They also help to distinguish between the various types of tissue in the body, because the protons in different types of tissue realign at different speeds and produce distinct signals.

In the same way that millions of pixels on a computer screen can create complex pictures, the signals from the millions of protons in the body are combined to create a detailed image of the inside of the body.

Key Point #7: the protons combine to create images of the body.

How MRI works

http://kidshealth.org/teen/cancer_center/diagnostic_tests/mri.html#

How MRI works

Discuss the steps to the design process. Be sure to know these steps! Refer back to quiz #3 for reference!

Review for Test

Review for Test

Partner 1

DNA When was DNA

discovered? What is DNA’s structure? List the parts of DNA. Who discovered DNA? What is the purpose of

DNA? Where is DNA stored?

Partner 2

Gel Electrophoresis How is it used? How is DNA separated? What is DNA’s charge? What type of molecules

move?

Review for Test

Partner 1

DNA Extraction Define extraction: What is the purpose of

the soap and the meat tenderizer?

Define lyse and emulsify. Where is DNA released

from?

Partner 2

MRI Define MRI: What is the body made

up of? What aligns in an MRI? Does MRI use radiation? What creates images?