Science - Lesson #7: Blood Transfusions

Lesson # 7:

Blood Type and Transfusions

Learning Intention:

Students will be able to explain how blood cells have different types of antigens and humans have antibodies to some of them causing an immune response.

Success Criteria:

Describe how the immune system recognizes antigens by their shape.
Explain why blood types are important when receiving a transfusion.
Apply my knowledge of the immune system to practice questions regarding blood transfusions.

Standards:

HS-LS1-2: Develop and use a model to illustrate the hierarchical organization of interacting systems that provide specific functions within multicellular organisms.

Reminders:

Immune System End of Unit Exam this Thursday, March 12th
Mock Regents on April 15th after school. If you come, we will drop your lowest test grade.

Blood Type and Transfusions_ A Biology Lesson.wav

Something looks Sus'

Looping Warm-Up

(5 min)

Directions:

1) Identify which one is wrong.

2) Explain in detail why the students answer is wrong.

3) Fix their answer to make it correct.

Question #1

Question #2

Question #3

State one reason why there is less energy available at each trophic level, going from the first to third trophic level.

Student Response #1

When trees are cut down they do not make as much oxygen, so there is less oxygen for people to breath.

Student Response #2

As you increase in trophic level, only 10 percent of energy is carried to the trophic level above. The rest is lost as metabolic waste and heat.

Student Response #3

The human heart is constantly beating and therefore its cells need a lot more energy than skin cells. The mitochondria is where energy is made during the process of cellular respiration. Therefore, heart cells would have more mitochondria than skin cells, to supply the energy (ATP) the heart needs to function.

Part 2:

Turn n'Talk

(5 min)

Because their aren't enough human kidneys, scientists are testing implanting genetically modified pig kidneys. This is called xenotransplantation.

On the first patient who received the pig kidney, the surgery was going well but half-way through, the doctors made a mistake and accidentally hit an artery. The patient started bleeding out on the operating table. The surgeons needed to get her blood fast!

Question:

Can the doctors just give her anyone's blood?

Why/Why not?

Part 3:

Active Reading

/Frayer Model

(15 min)

Directions:

Step 1) Actively read the article.

Step 2) Write THREE (3) Annotations as you read:

A) ONE (1) Connection to Life

B) ONE (1) Question you have

C) ONE (1) Main Idea Summarized

Step 3) After you have read and annotated, answer two of the four questions on the Frayer Model below:

Blood Types and Blood Transfusions

Blood types play a critical role in medicine, especially during blood transfusions. Every person’s blood belongs to one of four main types: A, B, AB, or O. These labels are based on the presence or absence of specific molecules called antigens on the surface of red blood cells. Antigens act like identification tags, helping the body recognize its own cells. If the wrong blood type is given during a transfusion, the immune system may attack the donated blood, leading to dangerous complications. This makes understanding blood types essential for safe medical care.

Antigens and Antibodies: The Body’s Security System

Each blood type has a unique combination of antigens and antibodies. For example, Type A blood has A antigens on its red blood cells and anti-B antibodies in its plasma (the liquid part of blood). Conversely, Type B blood has B antigens and anti-A antibodies. Type AB has both A and B antigens but no antibodies against them, while Type O has no antigens but both anti-A and anti-B antibodies. Antibodies are proteins produced by the immune system that target foreign invaders, such as incompatible blood cells. If someone with Type A blood receives Type B blood, their anti-B antibodies will attack the donor’s B antigens, causing red blood cells to clump together—a process called agglutination.

The Immune System’s Role in Transfusions

When incompatible blood is introduced, the immune system springs into action. White blood cells, like phagocytes / macrophages, help identify and destroy foreign cells. Antibodies bind to the antigens on the donor’s red blood cells, marking them for destruction. This triggers inflammation and can block blood vessels, leading to organ damage or even death. This reaction highlights why blood type matching is crucial. The immune system’s job is to protect the body, but in the case of a transfusion error, its defenses can become harmful.

Universal Donors and Recipients

Type O blood is often called the universal donor because it lacks A and B antigens, reducing the risk of triggering an immune response in the recipient. On the other hand, Type AB individuals are universal recipients because their plasma contains no anti-A or anti-B antibodies, allowing them to safely receive any blood type. However, even with these roles, doctors still prioritize using the exact blood match whenever possible to minimize risks. This system ensures that blood transfusions save lives without putting patients in danger.

Frayer Model Transfusion

Part #4:

Turn and Talk

The patient's husband tells the doctors that her blood type is B.

Question:

What blood types can the patient safely receive?

Part 5

Stop n' Jot

(3 min)

Key Concepts:

1) Blood cells have antigens on the surface. There are four antigen possibilities A, B, AB and O.

2) Blood type is determined by which antigen is on the blood cell membrane.

A = A antigen

B = B Antigen

AB = AB Antigen

O = No Antigen

3) You can only receive blood with the same antigen or no antigen. If you receive blood with a different antigen (Blood type B gets blood type A) your body will attack the received blood and you will have symptoms similar to an allergic reaction.

Part 6:

Exit Ticket

(5 min)

Ballet

Jazz

Hip-Hop

Page updated

Google Sites

Report abuse