FL #14 Immune System 10BC

Antigen-binding

sites

Antigen Antibody

Section 40-2

Figure 40–8 Structure of an Antibody

bacterium

•The bacterium is an antigen

An infectious disease is caused by

PathogensBacteria, viruses, &

fungi (germs).

•Antibodies-protein that helps destroy pathogens

Has 2 antigen binding sites Pathogen invades bodyAntigens on pathogen recognized by some B cells

Specific DefensesA. Humoral immunity-Immunity against pathogens in the body fluids (blood & lymph)

1-B cells (WBC) lymphocyte-produce antibodies

Antigen/antibodies2- Activated B cells grow and

divide rapidly (a million)3-Produce specialized B cells-

plasma cells (T cells help with this also)

4-Plasma cells-release antibodies into the blood to attack the pathogen causing infection

A person who receives a vaccine for the flu-

influenzaIs able to produce

antibodies against the flu

When a person receives a vaccine(shot) their body

create plasma cells (B cells) that can produce antibodies against a specific pathogen. (flu, polio, hepatitis)

Function of Antibodies:

Attach to antigens and attract phagocytes which engulf (eat) the antigens

phagocytes-engulf & destroy bacteria –most WBC are this type

“phag”=eat, “cytes”=cell

Inflammatory ResponsePathogens detectedMillions of WBC’s produced to

fight infectionBlood test reveals increase in

WBC’s-body is dealing w/ a serious infection

Immune system releases chemicals that increase core temperature

FEVER- INCREASED body temp

Many pathogens survive in a narrow temp. range

Elevated temp:1) slows down or stops growth of pathogens

2) increase heart rate, WBC’s get to infection quicker

3)Speeds activities of WBC’s & rate of chemical reactions that repair damaged tissues

1. (10b) Humoral immunity is carried out by A.Killer T CellsB.LymphocytesC.AntibodiesD.macrophages

2. (10b) In the figure below the red bacterium represents a A.Antigen or pathogenB.AntibodyC.Killer T CellD.Antigen binding site

E

3. (10b) Which of the following is the function of antibodies in the immune response?A.Antibodies produce

antibiotics.

B.Antibodies attach to antigens and attract phagocytes which engulf & destroy the antigen.

C.Antibodies produce interferon.

4. (10c) When a person receives a vaccine, his or her body creates a memory thatA.Receives antibodies against a

specific pathogen B.Creates plasma cells that can

produce antibodies against that specific pathogen.

C.Has polio antibodies in the bloodD.Has antipolio killer T cells in

blood

A. Preventing Viruses from replicating

D. Growing green mold that stops bacterial growth

B. Killing infected cellsC. Helping leucocytes identify pathogens

5. 10B Antibodies fight infections by