How do scientists figure out how to cure diseases? Watch this video to learn more about researching systems and disease.
Lesson B14: Researching Systems and Disease
Figure B.4.14.1 – Influenza is caused by viruses.
Figure B.4.14.2 – One influenza symptom is a high fever.
Figure B.4.14.3 – Flu immunizations can prevent the disease from spreading.
Reading and Materials for This Lesson
Science in Action 8
Reading: Pages 154–158
Materials:
No additional materials are needed for this lesson.
Influenza
Influenza, or the flu, is a virus-caused disease. Flu symptoms include a high fever, sore throat, achy muscles, and tiredness. The flu is most dangerous to very young and very old people.
Influenza viruses are constantly changing into new forms. Flu outbreaks happen every year, caused by new types of influenza viruses. Medical researchers create a different flu vaccine every year, based on their best observations about which flu viruses
are likely to spread among people. Sometimes influenza viruses change and infect people before a vaccine can be made to stop them. This is why making flu vaccines is challenging.
Watch More
The Flu Can Change the World
This video explains more about how influenza spreads and why flu viruses change all the time.
Lesson Activity
Vaccinations
Healthcare professionals recommend that people get vaccinations, or immunizations, against life-threatening diseases. Young children are given a number of immunizations against dangerous diseases. Some of these vaccinations require additional
booster shots in adulthood. People travelling outside of Canada often need vaccinations from diseases not found in Canada.
In recent years, some people in developed countries have chosen not to vaccinate themselves or their children. This has led to outbreaks of some diseases that were once eliminated. You can learn more about your own vaccination history through your
family doctor or school nurse.
In this lesson activity, you will collect information and learn more about vaccinations.
Draw a box in the centre of the page titled “Vaccinations”.
Draw 4 lines coming out of the centre box, and draw a box at the end of each line. Title these boxes:
How do vaccines work?
Why should people get vaccinated?
Descriptions of life-threatening diseases that are prevented by vaccines.
Why do some people choose not to get vaccinated?
Watch these videos. As you watch the videos, listen for examples of information that could answer the questions on your mind map. Pause the video when you hear an example and summarize the example in the correct section of your mind map.
These videos explain how vaccines work.
These videos explains how vaccines protect against dangerous diseases, and why some people choose not to get vaccinated.
This video explains how getting a vaccination helps protect other people from disease.
Is it dangerous to get a vaccine? Watch this video to learn more about the low risk of vaccines.
Visit these websites. As you read the information on the websites, look for examples of information that could fit under the headings on your mind map. Summarize the examples in the correct section of your mind map.
Figure B.4.14.4 – Melanoma is a type of skin cancer.
Figure B.4.14.5 – A tumour is a group of abnormal cells in the body.
Figure B.4.14.6 – Radiation therapy is used to target cancer cells inside tumours.
Cancer
Cancer is not an infectious disease that spreads from one person to another. Cancer happens when abnormal body cells start growing out of control.
Abnormal body cells form for several reasons. Cells often make random mistakes when they divide into new cells to replace old dead cells. Sometimes body cells become damaged from the environment, such as from excess exposure to UV light, or from from
toxic substances like tobacco smoke. Certain viruses are linked to creating abnormal body cells.
We all have abnormal cells in our bodies, which naturally die or are killed by the immune system. If an abnormal cell starts reproducing out of control, we call it cancer. A group of abnormal cells forms a tissue called a tumour. Cells can break off
the initial tumour and reproduce in other parts of the body, spreading the cancer. Cancer tumours and cells disrupt normal body functions, which eventually causes a person to die.
There are many different kinds of cancer. Many cancers are named after the body part where they start growing, such as liver cancer and lung cancer. Leukemia is a cancer in the bone marrow which affects the production of new blood cells. Melanoma
is a common type of skin cancer. Melanoma is preventable because it is most often caused by too much exposure to the Sun and tanning beds.
Many cancers, especially if they are caught early, can be treated and cured. Cancer patients often undergo surgery to remove tumours. They take chemotherapy drugs or have radiation treatments to kill any remaining cancer cells in the body. Medical
researchers are constantly trying to develop new cancer treatments. Their efforts have been successful at increasing the survival rate of cancer patients.
Figure B.4.14.7 – Cancer cells are killed with a strong medicine called chemotherapy.
Figure B.4.14.8 – There are many medical procedures used to treat and control cancers.
Watch More
The Fight Against Cancer
Watch this video to learn about how cancer tumors form and spread throughout the body.
Leukemia is a cancer that affects the production of blood cells. Watch this video to learn more about leukemia and how it is treated.
Researchers are developing new types of MRI scans to treat brain tumours more effectively.
Researchers produced a cancer drug that makes the body’s own immune system fight against cancer cells.
Connections
Figure B.4.14.9 – Research teams run many tests in their search for effective medical treatments.
Figure B.4.14.10 – Each small change in an ingredient or technique requires a new set of tests.
Figure B.4.14.11 – Many technologies are used in medical research.
Connections – Career >> Medical Research
Most sick patients only come into contact with doctors and nurses. However, lots of people work behind the scenes in health care, to treat and cure diseases. Medical researchers have a very important role to play in curing disease. Medical researchers
usually study one specific disease. They do many experiments and tests to figure out how the disease is caused and how it spreads. Based on their knowledge of a disease, medical researchers come up with ideas for cures. They do more tests to determine
if their experimental treatments are effective on patients.

Watch More
What is a Medical Researcher?
What does a medical researcher do? Watch this video to learn more.
This video explains the process of becoming a medical laboratory technologist in Canada.
Figure B.4.14.12 – Smallpox is an eradicated disease.
Figure B.4.14.13 – Health organizations are working on eradicating malaria.
Eradicating Disease
A disease is eradicated when it is completely eliminated from all people on Earth. Worldwide vaccination against a disease reduces and eventually eliminates its ability to infect people. Smallpox is the only human disease that has been eradicated
completely, but polio and malaria are on their way to eradication. A major part of eradicating diseases involves educating people about the safety and effectiveness of vaccines. People around the world refuse immunizations for various reasons, such
as believing they are unsafe.
Watch More
Can We Ever Completely Eliminate a Disease?
Smallpox was eradicated in 1979. Watch this video to learn the story of how humans eradicated smallpox.
Why is it so hard to eradicate a disease? Watch this video to learn more.
Figure B.4.14.16 – Penicillin is a common antibiotic.
What Are Antibiotics?
 Antibiotics
are substances that kill bacteria. Antibiotics such as penicillin are effective at treating bacterial infections. Some common bacterial infections include strep throat, infected wounds, urinary tract infections, pneumonia, and ear infections. Antibiotics
do not kill viruses. Since colds and influenza are caused by viruses, antibiotics are not effective at treating these diseases.
People have started overusing antibiotics. Patients sometimes ask doctors to prescribe antibiotics for a cold or the flu, when antibiotics won’t have any effect. Antibiotics prevent farm animals from getting sick and dying. As a result, farmers
often overuse antibiotics in cows, pigs, and chickens.
The problem with antibiotic overuse is that some bacteria have started changing and becoming resistant to the effects of antibiotics. Antibiotics don’t kill these “superbugs”. For example, a type of antibiotic-resistant bacteria called MRSA can
infect open wounds. A person with a weak immune system can’t defend against this bacteria, and antibiotics do not kill this bacteria. Something as simple as a papercut infected with MRSA could cause a person to die.
Watch More
The Use and Abuse of Antibiotics
How do antibiotics work? Watch this video to learn more.
How do “superbugs” develop? Watch this video to learn more.
Scientists are currently researching ways to kill antibiotic-resistant bacteria. Watch these videos to learn more.
Make sure you have understood everything in this lesson. Use the Self-Check below, and the Self-Check & Lesson Review Tips to guide your learning.
Unit B Lesson 14 Self-Check
Instructions
Complete the following 6 steps.
Don't skip steps – if you do them in order, you will confirm your
understanding of this lesson and create a study bank for the future.
ANSWER all the questions on the downloaded quiz in the spaces provided. Think carefully before typing your answers. Review this lesson if you need to. Save your quiz when you are done.
COMPARE your answers with the suggested "Self-Check Quiz Answers" below. WAIT! You didn't skip step 2, did you? It's very important to carefully write out your own answers before checking the suggested answers.
REVISE your quiz answers if you need to. If you answered all the questions correctly, you can skip this step. Revise means to change, fix, and add extra notes if you need to. This quiz is NOT FOR MARKS, so it is perfectly OK to correct
any mistakes you made. This will make your self-check quiz an excellent study tool you can use later.
SAVE your quiz to a folder on your computer, or to your Private Files. That way you will know where it is for later studying.
CHECK with your teacher if you need to. If after completing all these steps you are still not sure about the questions or your answers, you should ask for more feedback from your teacher. To do this, post in the Course Questions Forum,
or send your teacher an email. In either case, attach your completed quiz and ask; "Can you look at this quiz and give me some feedback please?" They will be happy to help you!
Be a Self-Check
Superhero!
Self-Check Quiz Answers
Click each of the suggested answers below, and carefully compare your answers to the suggested answers.
If you have not done the quiz yet – STOP – and go back to step 1 above. Do not look at the answers without first trying the questions.
If increased numbers of people stop getting vaccines for dangerous diseases, people lose their “herd immunity”. We could see life-threatening diseases outbreak, infect, and possibly a wide population of people again. This threat can be prevented
by vaccinations.
Clinical trials are needed in medical research to make sure a drug is effective against a disease, and also to make sure that the drug doesn’t cause negative unintended side effects. Trying out a new drug on a small group of patients allows
researchers to make sure that a drug is safe and effective, before releasing it to a wider population.
The overuse of antibiotics has led to some types of bacteria becoming resistant to antibiotics. Existing antibiotics are becoming less effective against some types of bacterial infections. Research to find new antibiotics is important to prevent
deaths from antibiotic-resistant bacterial infections.
Colds are caused by viruses, not bacteria. Antibiotics do not kill viruses, so they are not effective on colds. Giving a patient antibiotics for a cold contributes to the problem of antibiotic overuse.
Doctors and nurses diagnose diseases and give medicines directly to patients. However, without medical researchers, doctors and nurses would not understand the causes of diseases and they would not have access to medicines that treat diseases.
Doctors and nurses use the knowledge discovered by medical researchers in order to treat patients. Without knowledge passed on by medical researchers, doctors and nurses could not be successful at their jobs.
Reading and Materials for This Lesson
