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Here’s a study guide that covers all of the topics you listed, broken down into categories for easier review:

1. Prokaryotes vs. Eukaryotes

• Prokaryotes:

• No membrane-bound nucleus.

• No organelles (except ribosomes).

• Smaller (typically 0.5-5 micrometers).

• Includes bacteria and archaea.

• Divide via binary fission.

• Eukaryotes:

• Membrane-bound nucleus.

• Have organelles (e.g., mitochondria, endoplasmic reticulum).

• Larger (typically 10-100 micrometers).

• Includes plants, animals, fungi, and protists.

• Divide via mitosis or meiosis.

2. Definitions:

• Phylogeny: The evolutionary history and relationships among species.

• Taxonomy: The science of classifying and naming organisms.

3. Three-Domain System with Assigned Kingdoms:

• Bacteria: Kingdoms – Eubacteria (true bacteria).

• Archaea: Kingdoms – Archaebacteria (extremophiles, such as thermophiles).

• Eukarya: Kingdoms – Animalia, Plantae, Fungi, Protista.

4. Characteristics of Eukaryotic Species:

• Membrane-bound nucleus and organelles.

• Can be unicellular (e.g., protists) or multicellular (e.g., animals, plants).

• Larger and more complex than prokaryotes.

5. Characteristics of Prokaryotic Species:

• Lack a nucleus and membrane-bound organelles.

• Smaller and simpler.

• Include bacteria and archaea.

6. Characteristics of Viral Species:

• Acellular (not made of cells).

• Composed of a protein coat (capsid) and sometimes an envelope.

• Require a host cell to replicate.

• Can be DNA or RNA viruses (single-stranded or double-stranded).

7. Species vs. Strains:

• Species: A group of organisms that can interbreed and produce fertile offspring.

• Strains: Variants within a species, often with slight genetic differences.

8. DNA Fingerprinting:

• A technique used to identify individuals or species based on unique patterns in their DNA.

9. Serology:

• The study of blood serum, used to identify antibodies or antigens.

• How it works: Antibodies bind to antigens, indicating the presence of pathogens.

10. Enzyme-Linked Immunosorbent Assay (ELISA):

• Direct ELISA: Used to detect antigens.

• Indirect ELISA: Used to detect antibodies.

• Sandwich ELISA: Detects both antigens and antibodies.

11. Gram Stain Reaction and Characteristics of Bacteria:

• Understand the shape (coccus, bacillus, spirillum) and arrangement (pairs, chains, clusters) of various bacteria.

• Gram-positive bacteria: Thick peptidoglycan, stain purple.

• Gram-negative bacteria: Thin peptidoglycan, stain pink.

• Diseases caused, transmission, habitat, and unique characteristics (e.g., acid-fast, intracellular vs extracellular) for the listed genera:

• Bartonella, Rickettsia, Burkholderia, Brucella, Salmonella, etc.

• Important bacteria like Mycobacterium (acid-fast), Chlamydia (intracellular), and Neisseria (diplococci).

12. Fungal Spores:

• Fungal spores are reproductive cells that can develop into a new organism.

• Characteristics: Some fungi produce asexual spores (e.g., conidia, sporangia), and others produce sexual spores (e.g., ascospores, basidiospores).

13. Fungi:

• Fungi can be unicellular (yeasts) or multicellular (molds).

• Dimorphic fungi: Can change form depending on temperature.

• Diseases: Aspergillus (lung infection), Candida (yeast infections), Histoplasma (respiratory), Mucor (systemic infections).

14. Mycosis Types:

• Systemic mycosis: Fungal infections that affect internal organs (e.g., Histoplasmosis).

• Subcutaneous mycosis: Fungal infections beneath the skin (e.g., Sporotrichosis).

15. Protozoa and Helminths:

• Protozoa: Single-celled eukaryotic organisms (e.g., Giardia, Plasmodium).

• Helminths: Parasitic worms (e.g., Taenia, Ascaris).

• Intermediate hosts: Host where a parasite develops but does not reproduce.

• Definitive hosts: Host where the parasite reaches maturity and reproduces.

16. Stages of Animal Virus Multiplication:

1. Attachment: Virus attaches to host cell receptors.

2. Entry: Virus or genome enters the cell.

3. Uncoating: Viral genome is released.

4. Replication & Transcription: Host cell machinery is used to replicate viral genome and produce proteins.

5. Assembly: New viral particles are assembled.

6. Release: New virions are released from the host cell.

17. Stages of Bacteriophage Multiplication:

• Lytic cycle: Results in the destruction of the host cell.

• Lysogenic cycle: Viral genome integrates into the host genome and replicates without killing the host immediately.

18. Prion Replication:

• Prions are misfolded proteins that cause other proteins to misfold, leading to diseases (e.g., Creutzfeldt-Jakob disease).

19. Cancer-Causing Viruses:

• Some viruses (e.g., HPV, Epstein-Barr virus) can integrate into the host genome, causing uncontrolled cell growth and cancer.

20. Virus Replication:

• DNA viruses: Replicate in the nucleus.

• RNA viruses: Replicate in the cytoplasm (positive-sense RNA serves directly as mRNA).

• Retroviruses: Use reverse transcriptase to convert RNA into DNA for integration into the host genome.

21. Reverse Transcriptase:

• Reverse transcriptase is crucial for retroviruses (e.g., HIV) to replicate their RNA genomes into DNA.

22. Viroids:

• Viroids are small, circular RNA molecules that cause disease in plants (not animals).

Enzyme-Linked Immunosorbent Assay (ELISA):

• Definition: A laboratory technique used to detect and quantify substances like proteins, antibodies, and hormones.

• Principle: Uses an enzyme-linked antibody to bind to the target antigen, causing a color change when a substrate is added.

• Types: Direct ELISA, Indirect ELISA, Sandwich ELISA, and Competitive ELISA.

Bacterial Characteristics & Gram Stain Reactions:

Bartonella

• Gram Reaction: Gram-negative

• Shape: Bacillus (rod-shaped)

• Arrangement: Single or in pairs

• Habitat: Intracellular in endothelial cells

• Disease: Bartonellosis (e.g., Cat scratch fever)

• Transmission: Flea bites, scratches from infected cats

• Unique Characteristic: Intracellular bacteria

• Cell Wall: Lacks peptidoglycan in typical amounts

Rickettsia

• Gram Reaction: Gram-negative

• Shape: Coccobacillus

• Arrangement: Single or pairs

• Habitat: Intracellular (within endothelial cells)

• Disease: Rocky Mountain spotted fever, typhus

• Transmission: Vectors (e.g., ticks, fleas)

• Unique Characteristic: Obligate intracellular pathogen

• Cell Wall: Contains lipopolysaccharides (LPS) but no typical peptidoglycan layer

Burkholderia

• Gram Reaction: Gram-negative

• Shape: Bacillus

• Arrangement: Single or in pairs

• Habitat: Soil, water

• Disease: Burkholderia infections (e.g., pneumonia in cystic fibrosis)

• Transmission: Aerosol, direct contact

• Unique Characteristic: Can be resistant to many antibiotics

• Cell Wall: Thin peptidoglycan layer with LPS

Brucella

• Gram Reaction: Gram-negative

• Shape: Coccobacillus

• Arrangement: Single

• Habitat: Intracellular (monocytes, macrophages)

• Disease: Brucellosis (Undulant fever)

• Transmission: Contact with infected animals, unpasteurized dairy

• Unique Characteristic: Obligate intracellular parasite

• Cell Wall: LPS with minimal peptidoglycan

Salmonella

• Gram Reaction: Gram-negative

• Shape: Bacillus

• Arrangement: Single or in pairs

• Habitat: Intestinal tract of animals

• Disease: Salmonellosis, Typhoid fever

• Transmission: Fecal-oral route

• Unique Characteristic: Motile, can survive in diverse environments

• Cell Wall: Typical Gram-negative with LPS

Ehrlichia

• Gram Reaction: Gram-negative

• Shape: Coccobacillus

• Arrangement: Intracellular (in white blood cells)

• Habitat: Leukocytes

• Disease: Ehrlichiosis

• Transmission: Ticks

• Unique Characteristic: Obligate intracellular bacteria

• Cell Wall: Lack peptidoglycan; atypical Gram-negative

Bordetella

• Gram Reaction: Gram-negative

• Shape: Coccobacillus

• Arrangement: Single

• Habitat: Respiratory tract

• Disease: Pertussis (whooping cough)

• Transmission: Droplets from cough/sneezing

• Unique Characteristic: Produces toxins (e.g., pertussis toxin)

• Cell Wall: Contains LPS and outer membrane proteins

Neisseria

• Gram Reaction: Gram-negative

• Shape: Diplococci

• Arrangement: Pairs

• Habitat: Human mucosal surfaces

• Disease: Gonorrhea, Meningococcal meningitis

• Transmission: Sexual contact (gonorrhea), respiratory droplets (meningitis)

• Unique Characteristic: Oxidase-positive, fastidious

• Cell Wall: Contains peptidoglycan and LPS

Pseudomonas

• Gram Reaction: Gram-negative

• Shape: Bacillus

• Arrangement: Single or pairs

• Habitat: Soil, water, hospital settings

• Disease: Pseudomonas infections (e.g., pneumonia, skin infections)

• Transmission: Direct contact, inhalation of aerosolized particles

• Unique Characteristic: Highly antibiotic-resistant

• Cell Wall: Contains LPS, endotoxins

Fungi Characteristics:

• General Characteristics: Eukaryotic, non-motile, chitin in the cell wall, reproduce via spores.

• Dimorphic Fungi: Yeast at 37°C (body temperature) and mold at 25°C (ambient temperature).

• Aspergillus: Causes Aspergillosis; common in immunocompromised individuals.

• Candida: Causes candidiasis (oral thrush, vaginal yeast infections).

• Histoplasma: Causes Histoplasmosis; found in bird and bat droppings.

• Mucor: Causes mucormycosis; found in decaying organic matter.

Systemic Mycoses & Subcutaneous Mycoses:

• Systemic Mycoses: Histoplasmosis, Coccidioidomycosis, Blastomycosis, Paracoccidioidomycosis.

• Subcutaneous Mycoses: Sporotrichosis, Chromoblastomycosis, Mycetoma.

Parasites:

• Trichomonas: Causes trichomoniasis, transmitted sexually.

• Giardia: Causes giardiasis, transmitted via contaminated water.

• Entamoeba: Causes amoebiasis, transmitted via fecal-oral route.

• Balamutia, Acanthamoeba: Causes brain infections, transmitted by contaminated water.

• Toxoplasma: Causes toxoplasmosis, transmitted via cat feces.

• Plasmodium: Causes malaria, transmitted by Anopheles mosquito.

• Trypanosoma: Causes sleeping sickness (T. brucei) and Chagas disease (T. cruzi).

• Taenia: Causes taeniasis, transmitted via undercooked pork/beef.

• Clonorchis sinensis: Causes clonorchiasis, transmitted by eating undercooked fish.

• Schistosoma haematobium: Causes schistosomiasis, transmitted via contaminated water.

• Ascaris lumbricoides: Causes ascariasis, transmitted via fecal-oral route.

• Enterobius vermicularis: Causes pinworm infection, transmitted via fecal-oral route.

• Necator americanus/Ancylostoma duodenale: Cause hookworm infection, transmitted through skin contact with contaminated soil.

Viral Replication and Prions:

• Stages of Animal Virus Multiplication: Attachment, penetration, uncoating, replication, assembly, release.

• Bacteriophage Multiplication: Attachment, penetration, biosynthesis, maturation, release (lytic cycle); incorporation of viral DNA into host DNA (lysogenic cycle).

• Prion Replication: Infectious prions induce misfolding of normal proteins, creating more prions.

• Mechanism of Cancer by Viruses: Viruses like HPV, Epstein-Barr virus, and Hepatitis B cause cancer by integrating their DNA into host DNA, causing uncontrolled cell division.

• Reverse Transcriptase: Found in retroviruses (e.g., HIV), reverse transcriptase converts RNA into DNA for integration into the host genome.

• Viroid: Small, circular RNA molecules that infect plants

Bacterial Disease Transmission and Cell Wall Components:

• Intermediate Host: Hosts that harbor the parasite for a temporary period, often as a developmental stage.

• Definitive Host: The host in which a parasite reaches its mature, reproductive stage.

• Unique Characteristics of Bacteria: E.g., Mycobacterium’s mycolic acid makes it acid-fast; Rickettsia’s intracellular lifestyle differentiates it from other bacteria.