Communicable Diseases and Plant Defenses

Study Notes

Communicable Diseases

Communicable diseases are illnesses caused by infectious agents like bacteria, viruses, fungi, or parasites.
Transmission routes can include direct contact, airborne droplets, contaminated food or water, or vectors.
Examples include influenza, HIV/AIDS, tuberculosis, and malaria.
Diagnostic methods range from observing symptoms to laboratory tests like blood tests and cultures.

Plant Defenses

Plants, lacking a mobile immune system like animals, employ various defense mechanisms to protect against pathogens and herbivores.
These defenses can be categorized as physical, chemical, and mechanical.
Physical barriers include the plant's cuticle, cell walls, and bark.
Chemical defenses encompass the production of toxins, antimicrobial compounds, and defensive proteins.
Mechanical defenses involve thorns, spines, and trichomes.
Some mechanisms are constitutive (always present), while others are induced in response to pathogen attack.

Non-Specific Defenses

Non-specific defenses, also known as innate immunity, are the body's first line of defense against pathogens.
These defenses provide a general response to a wide range of pathogens, not targeting a specific one.
Examples include the skin, mucous membranes, inflammatory response, fever, and phagocytosis.
Skin acts as a physical barrier, while mucous membranes trap pathogens.
The inflammatory response isolates infected areas and promotes healing.
Fever increases body temperature, slowing pathogen replication.
Phagocytes, like macrophages and neutrophils, engulf and destroy pathogens.

Monoclonal Antibodies

Monoclonal antibodies (mAbs) are identical antibodies produced in the laboratory from a single clone of B-cells.
They have a single specificity, targeting a particular antigen.
Compared to polyclonal antibodies, mAbs are more uniform and have higher specificity.
Production involves fusing a B-cell producing the desired antibody to a myeloma (cancer) cell, creating a hybridoma.
Hybridoma cells then produce large quantities of the specific antibody.
Monoclonal antibodies find broad applications in diagnostics, research, and therapeutics—specifically treating cancer, autoimmune diseases, and infections.
Examples include treatments for some types of cancer, autoimmune diseases like rheumatoid arthritis, and some viral infections.
Important aspects include the method of production, high specificity, and diverse applications.

Description

Explore the fascinating world of communicable diseases and plant defenses. This quiz covers how infectious agents cause illnesses and the various mechanisms plants use to protect themselves against pathogens and herbivores. Test your knowledge on these essential biological concepts!