Bio 202 Exam #2 Flashcards

Questions and Answers

What are antibodies?

Antibodies are specialized, Y-shaped proteins that bind to the body's foreign invaders, such as viruses, bacteria, fungi, or parasites. They are produced by B-lymphocytes.

How do antibodies facilitate destruction of an invading organism?

Antibodies protect against bacteria that multiply outside cells by facilitating uptake of the pathogen by phagocytic cells. Mechanisms include agglutination, precipitation, opsonization, complement fixation, and neutralization.

What cells produce antibodies?

B cells, which are a type of lymphocyte, produce antibodies used to attack invading bacteria, viruses, and toxins.

How was Helga's body able to produce antibodies against E.coli O157 if she had never encountered it before?

Helga's immune system selects among a large number of randomly generated B-cells. B-cells capable of producing antibodies against the E.coli pathogen are selected and activated. Signup and view all the answers

What role did macrophages presumably play in the production of antibodies against the E.coli strain?

Macrophages were likely the first immune cells to attack E.coli. After engulfing and destroying the bacteria, they used MHC II complexes to present bacterial protein to helper T-cells, which activated the appropriate B-cells. Signup and view all the answers

What role did helper T cells presumably play in the production of antibodies against the E.coli strain?

Helper T-cells activate B-cells after being shown an antigen by a macrophage or other antigen presenting cell. Signup and view all the answers

How can Rothgar's immune system produce antibodies capable of attacking a wide variety of pathogens?

Rothgar's bone marrow stem cells continually produce new B-cells. Each new B-cell randomly rearranges the antibody gene so that each one has different specificity. Signup and view all the answers

If Helga encounters the same strain of E.coli again, why will she probably not get very sick?

Some of the B-cells activated during her immune response will become memory B-cells that quickly produce antibodies if E.coli is encountered again. Signup and view all the answers

What are MHC proteins?

MHC proteins are cell surface proteins coded by a set of polymorphic genes essential for the adaptive immune system. Signup and view all the answers

Why are MHC proteins important for the immune response to E.coli O157?

MHC proteins bind to antigens from pathogens and display them on the cell surface for recognition by T-cells, allowing for a quicker response if the virus is encountered again. Signup and view all the answers

How does blood circulation differ before and after birth?

Before birth, blood flow mainly bypasses the lungs through the foramen ovale and the ductus arteriosus. After birth, these openings close and blood flows normally through the heart. Signup and view all the answers

What does the thymus do?

The thymus gland produces hormones and is part of the immune system by training and developing T-lymphocytes/T cells. Signup and view all the answers

Study Notes

Antibodies

Specialized Y-shaped proteins that target foreign invaders like viruses, bacteria, fungi, and parasites.
Function as a part of the immune system’s search-and-destroy mechanism.
Produced by B-lymphocytes.

Mechanisms of Antibody Action

Facilitate bacterial destruction primarily by aiding phagocytic cells in pathogen uptake.
Key mechanisms include agglutination, precipitation, opsonization, complement fixation, and neutralization.

B-cell Production

B-cells, a type of lymphocyte, are responsible for antibody production.
Function to attack invading microbes, toxins, and viruses.

Immune Response to E. coli O157

The immune system selects B-cells that can produce specific antibodies against new pathogens like E. coli O157.
Activation occurs after encountering the pathogen.

Role of Macrophages

Engage and eliminate pathogens before presenting bacterial proteins via MHCII complexes.
Assist in activating helper T-cells to stimulate B-cell responses.

Role of Helper T-cells

Facilitates B-cell activation through antigen presentation by macrophages.
Vital for triggering the antibody production process against antigens.

Diversity of Antibody Production

Bone marrow stem cells in Rothgar continually generate new B-cells.
Each B-cell undergoes random genetic rearrangement for varying antibody specificity.

Memory B-cells

Some activated B-cells transform into memory B-cells after an initial immune response.
Enable rapid antibody production upon re-exposure to the same pathogen.

Major Histocompatibility Complex (MHC) Proteins

A complex of genes coding for cell surface proteins critical to the adaptive immune response.
MHC molecules are essential for displaying pathogen-derived antigens to T-cells.

Importance of MHC in E. coli Response

MHC proteins bind to antigens, facilitating T-cell recognition.
Play a role in shaping future immune responses to pathogens.

Changes in Blood Circulation Before and After Birth

Prenatal blood flow bypasses the lungs via the foramen ovale and ductus arteriosus.
Post-birth changes redirect blood flow through the heart and to the lungs.

Function of the Thymus

Produces hormones and is critical for the development of T-lymphocytes (T-cells) in the immune system.
Proportionately larger in children compared to adults, reflecting its role in early immune development.

T-cell Receptors and Lymph Nodes

T-cell receptors in lymph nodes provide support and necessary conditions for T-cells after their activation and functionality.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Prepare for your Bio 202 exam with these flashcards focused on antibodies and their role in the immune system. Each card describes key concepts that are essential for understanding how antibodies aid in defending the body against various pathogens.