Eukaryotic Microbes Overview

Eukaryotic Microbes

• Fungi include yeasts, molds, and mushrooms
• Protozoa include Plasmodium
• Algae are a type of microbe
• Viruses are composed of genetic material (DNA or RNA), a protein shell, and sometimes a lipid envelope
• Viruses are non-metabolic and cannot reproduce independently
• Viruses invade cells to reproduce
• Viruses are non-cellular microbes

Representative Sizes of Microbes

• 1 μm = 1,000 nm
• Microbes can vary in size, with some visible to the naked eye (like some protozoa and algae), and others (like many bacteria) requiring a microscope.
• Microbes' sizes range greatly from visible to almost invisible to the naked eye

Other Challenges with Microbe Definitions

• Some microbes form biofilms, which are made of cells with various functions
• Some microbes grow in mycelial filamentous structures
• Some microbes (like some protozoa and algae) are visible to the naked eye
• Animals, mites, and roundworms are not considered microbes

Microbes Shape Human History

• Microbes play a crucial role in maintaining life
• They fix nitrogen, release oxygen, degrade organic matter, and build organic matter

Medical Microbiology and Immunology

• Germ theory: Specific diseases are caused by microscopic organisms
• Diseases like cholera, HIV, and more have significance in crowded areas during times of conflict
• Florence Nightingale's work demonstrated the significance of sanitation in reducing mortality rates
• Robert Koch developed a scientific method to establish the cause of infectious disease

Koch's Postulates

• Microorganisms identified with disease must be consistently found in every case of the disease
• Microorganisms must be grown in pure culture
• Introduction of the pure culture to healthy individuals must cause the same disease in the healthy individual
• Microorganisms must be isolated from the affected individuals and confirmed in a pure culture

Controlling Infectious Diseases

• Prevention includes immunization, hygienic practices, and sterilization
• Treatment involves antivirals, antifungals, antiprotozoals, and antibiotics

Vaccines

• Edward Jenner developed the concept of vaccination by using cowpox to prevent smallpox
• Louis Pasteur developed attenuated vaccines to induce immunity without causing severe symptoms
• Rabies is a disease which vaccines were developed for and attenuated vaccines are used today
• Microbes can cause disease and be useful and have played and continue to play a crucial role in human history.

Antiseptics and Disinfectants

• John Snow stopped a cholera epidemic by identifying its cause and preventing access to the source
• Ignaz Semmelweis and Joseph Lister improved hygiene practices to prevent surgical infections
• Alexander Fleming discovered penicillin, which revolutionized medicine by fighting bacterial infections

Antibiotics

• Penicillin, discovered by Alexander Fleming, was later purified and mass-produced by Florey and Chain.
• Overuse of antibiotics can lead to antibiotic resistance rendering many bacteria, or other microbes unable to be treated, thus limiting the usefulness of such treatments.

This quiz covers the diverse world of eukaryotic microbes, including fungi, protozoa, and algae. It discusses their defining characteristics, sizes, and the challenges in classifying them. Explore the nuances that differentiate these organisms from other life forms like viruses.