Biology 12

SKILL FOCUS

Initiating and planning

Predicting

Performing and recording

Analyzing and interpreting

Investigation 4 • B

130 MHR • Unit 2 Homeostasis

Pre-lab Questions

How widespread are food allergies in your class?

Which are the most common food allergies among

students in your class?

Problem

What will the data you collect and analyze indicate

about the importance of food allergies?

Prediction

Predict how many people in your class have food

allergies.

Procedure

1.Design a questionnaire to collect data. Your

questionnaire should include questions that

determine whether or not a person is aware of any

food allergy he or she has, which foods the person

is allergic to, and what symptoms they experience.

2.Distribute your questionnaire to the students in your

class. Keep in mind that the smaller your sample

size, the less dependable your results are. Clearly

state that this survey is completely voluntary.

Students should feel free to participate or not

participate: respect for privacy is essential. Those

who do participate should be urged to answer

questions as completely and accurately as possible.

They need not put their names on the questionnaire.

Food Allergy Survey

Most people who have food allergies are aware of the foods or food products they

should avoid. In this investigation you will gather data on how widespread food

allergies are in your class and determine which are most common.

Biology At Work

Immunologist

Dr. John Jacob Lyanga

Back to the Roots

“Early in life,” Dr. John Jacob Lyanga remembers, “I started

on the road of one day becoming a healer.” Dr. Lyanga

grew up in Tanzania. “In our culture, dogs were very

important because they were used for hunting and were

responsible for the surveillance of cattle and premises. If

the dogs became ill, it was my job as the oldest in the

family to make them well. I had to learn the medicinal

properties of local plant roots and leaves.”

Natural Killer Cells

Throughout his life, Dr. Lyanga wondered why some

forms of treatment work and others do not, depending

largely on the patient. After studying medicine in Tanzania

and then England, Dr. Lyanga obtained an internship at

Queen’s University in Kingston in 1973. This marked the

beginning of his study of immunology. Here he

encountered patients receiving kidney transplants and

was puzzled as to why some people accepted while

others rejected a transplanted kidney. Dr. Lyanga learned

that “kidney rejection is a harmful immune reaction; the

body is attacking the donor kidney in order to kill it or get

rid of it. Certain cells can kill other cells if they appear

foreign or threatening to the host. They are called natural

killer cells (or NK cells).” The study of immunology seeks

to understand why some cells accept, while others react

against, foreign cells.

The Allergy Capital of Canada

Today, Dr. Lyanga works as a doctor in allergy and clinical

immunology in Windsor, Ontario, sometimes referred to