Understanding Biotic Potential, Ecosystems, and Components

The biotic potential is the maximum reproductive capacity of living organisms under ideal environmental conditions. It represents the highest possible vital index of a species, occurring when the species has the highest birth rate and the lowest mortality rate. Primary factors determining biotic potential include the organism’s rate of reproduction and its litter size – the number of offspring produced at one birth.

Under ideal environmental conditions, a species’ capacity to reproduce is known

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Respiratory Infections and Mononucleosis: Diagnosis and Treatment

Respiratory Infections: A Comprehensive Overview

Upper Respiratory Tract Infections

Pharyngoamigdalitis

Most cases are viral, so antibiotics should only be administered when the patient has a fever > 38°C, exudate, anterior cervical lymphadenopathy, and absence of cough. The preferred treatment is Amoxicillin 500mg/8h for 10 days.

Rhinitis

Most cases are mucopurulent and viral. Antibiotics are only indicated when symptoms persist for more than 7 days, often involving sinus involvement.

Sinusitis

Common

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Common Infectious Diseases: Malaria, Diarrhea, TB, AIDS, Flu & More

Common Infectious Diseases

Malaria

Malaria is caused by protozoan microorganisms of the genus Plasmodium, transmitted by Anopheles mosquitoes. These parasites infect liver cells and erythrocytes (red blood cells), where they reproduce. This cellular exploitation leads to episodes of intense fever, chills, anemia, and spleen inflammation due to the proliferation of defensive cells.

Malaria can be treated with medication, but reinfection is possible. A fully effective vaccine is not yet available.

Diarrheal

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22 Key Pathogens: Diseases, Symptoms, and Prevention

  1. Salmonella enteritidis

    • Genus/Species: Salmonella enteritidis
    • Disease: Salmonellosis (food poisoning)
    • Symptoms: Fever, stomach cramps, diarrhea
    • Virulence Factors: Invades intestinal cells, produces enterotoxins
    • Mechanism: Enterotoxins disrupt ion transport, causing diarrhea
    • Treatment: Rehydration; Ciprofloxacin or Azithromycin in severe cases
    • Prevention: Cook poultry thoroughly, practice good hand hygiene
    • Break Chain: Destroy animal reservoirs, inspect food products
  2. Geobacillus stearothermophilus

    • Genus/Species:
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Anthrax, Bacillus Cereus, and Listeria: Characteristics, Pathogenesis, and Prevention

Bacillus anthracis:

Bacillus anthracis can enter through the skin, gastrointestinal tract, and the airway (less frequent but more lethal).

  • Gram-positive bacilli
  • Facultative anaerobe
  • Forms spores that can survive for years
  • Undemanding growth
  • Presents a polypeptide capsule (poly-D-glutamic acid)
  • Coded by 3 genes: capB, capC (Plasmid 1)
  • Plasmid 2 (B. anthracis virulence)

Encodes 3 Exotoxins:

  1. Protective antigen (binds to the host cell)
  2. Edema factor
  3. Lethal factor

Edema Toxin:

Edema factor + protective antigen = responsible

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Anthrax, Tetanus, Staphylococcus, and Cholera: Identification, Transmission, and Prevention

Bacillus anthracis (Anthrax)

Identification: The first infectious disease, Anthrax, is caused by Bacillus anthracis, a gram-positive, aerobic bacterium that forms endospores and is encapsulated. It can be found in ordinary cultivars.

Transmission: Transmission of Anthrax typically occurs through contact with animals, inhalation, or ingestion of contaminated, uncooked meat.

Manifestations: Initially, cutaneous anthrax presents as a superficial, itchy lesion at the site of entry. This lesion becomes

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