Biology 101: Exploring the Diversity of Life

1. Bacteria & Archaea

Classifications

Three Domains (Woese: small subunit rRNA): Bacteria, Archaea, Eukarya. Comparison of three domains, relationships; ‘Prokaryotes’ (=Monera) paraphyletic. [Monophyletic vs. paraphyletic – know the meaning of these terms]

Prokaryotic Cell Structure

Bacterial cell wall with peptidoglycan, Gram +/– difference, cell shape, capsule, flagellum, plasmid, endospores; archaeal cell membrane branched isoprene chains.

Reproduction & Genetic Novelties

Binary fission,

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Levels of Organization and Human Body Systems

Levels of Organization: Complexity in Living Matter

Atomic and Molecular Level

Matter is made up of atoms, which come together to form molecules held by chemical bonds. Atoms in living matter are called bioelements. Molecules in living things are biomolecules.

Inorganic Molecules

These have a simple chemical structure and include water and minerals. They are found in both living and non-living matter.

Organic Biomolecules

These are found in living things and contain carbon. They are usually polymers and

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From DNA to Protein: Understanding Gene Expression

The Central Dogma of Molecular Biology

DNA affects the traits of an organism by providing the instructions for synthesizing proteins. Gene expression involves two main phases: transcription and translation.

Messenger RNA (mRNA) molecules contain information that is used to synthesize polypeptides. To begin transcription, RNA polymerase must bind to a segment of DNA called the promoter. The strand of DNA that is not transcribed is called the coding strand.

Transcription and Translation

During translation,

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Space Maintainers in Dentistry: A Comprehensive Guide

Space Maintainers in Dentistry

Contraindications of Space Maintainers

  • No alveolar bone over erupting tooth
  • Space closure desired for congenitally missing tooth
  • Gross discrepancy requiring corrective orthodontics
  • Excessive space
  • High caries activity and poor oral hygiene
  • Poor patient and parent cooperation

Requirements of Space Maintainers

  • Passively maintain the space and prevent rotation or tipping of the abutment tooth
  • Not cause damage to teeth or injury to soft tissue
  • Not interfere with growth and development,
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Keeping Healthy: Understanding Diseases and Prevention

Keeping Healthy

Lifestyle Diseases

Types of Microorganisms That Can Cause Disease:

Virus:
  • Flu (Gripe)
  • Polio
  • Common Cold (Resfriado Común)
  • AIDS (SIDA)
  • Measles (Sarampión)
  • Meningitis
  • Rabies
  • Chicken Pox (Varicela)
  • Papilloma

Microorganisms that can only live and reproduce inside living cells.

Bacterium:
  • Tonsillitis (Anginas)
  • Tuberculosis
  • Plague (Plaga)
  • Cystitis
  • Tetanus
  • Botulism (Enfermedad producida cuando te comes alimentos en malas condiciones)
  • Cholera (Cólera, Gastroenteritis)

One type of single-celled microorganism.

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Understanding Monera: Characteristics, Types, and Importance

Monera

General Characteristics

  • Cosmopolitan distribution (found everywhere)
  • Prokaryotic cells (lack true nucleus and membrane-bound organelles)
  • Circular DNA
  • Rigid cell wall
  • Heterotrophic (most species) and some autotrophic
  • Vegetative and asexual reproduction
  • Decomposers, contributing to soil fertility

Types of Monera

1. Archaebacteria (Ancient Bacteria)

2. Eubacteria (True Bacteria)

  • Bacteria
  • Cyanobacteria

Bacteria

Discovery and History

Bacteria were first discovered by Anton Van Leeuwenhoek in 1675. Ehrenberg coined

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