Fundamentals of Virology
Introduction to Virology
Comparing Viruses and Cellular Life
Viruses are infectious, obligate intracellular parasites, while cellular life can reproduce independently.
Viruses possess either a DNA or RNA genome, while cellular life possesses a DNA genome.
Viruses require a host cell for ribosomes, energy sources, genome replication, assembly, and preformed components.
Ubiquity of Viruses
Viruses are everywhere and infect all life forms.
There are more viruses in a liter of seawater than humans on the planet.
Unraveling Genetics: From Ancient Insights to Mendel’s Laws
Introduction to Genetics
Genetics is the branch of biology responsible for studying biological inheritance. Biological inheritance refers to the capacity of living organisms to transmit their genetic information from one generation to the next.
Historical Perspectives on Heredity
Early Insights into Inheritance
Since the Neolithic period, as humans began to ponder the mysteries of life, the emergence of agriculture led to sedentary lifestyles. This allowed early civilizations to observe and influence
Read MoreKey Concepts in Earth’s History and Microbiology
Earth’s Ancient History and Life’s Emergence
Major Evolutionary Milestones
- Solar System Forms: Approximately 14 billion years ago (bya)
- Earth Forms: Approximately 4.6 bya
- Formation of Planet Earth: 4.5 bya
- Prokaryotes First Appear: 3.5 bya
- Eukaryotes First Appear: 1.8 bya
- Multicellular Organisms Appear: 1.5 bya
- Animals Appear in Fossil Record: 600 million years ago (mya)
- Fungi and Plants Colonize Land: 490 mya
- Early Humans Appear (Not Modern Man): 2.5 mya
Early Earth Conditions
- Initially fiery and chaotic.
- Atmosphere
Cell Division Fundamentals: Mitosis, Meiosis, and Genetic Principles
Essential Genetic Definitions
Understanding cell division begins with key genetic terms:
- Zygote: A fertilized egg.
- Genome: A cell’s complete set of DNA, packaged as a double-stranded molecule.
- Prokaryotic Genome: Typically a single, double-stranded DNA molecule forming a loop or circle within the nucleoid region.
- Plasmids: Found in prokaryotes, these are small, non-essential DNA molecules. Bacteria can exchange plasmids to acquire new genes, potentially leading to traits like antibiotic resistance.
- Eukaryotic
Life’s Fundamental Principles: Characteristics and Evolutionary Theories
Characteristics of Living Organisms
Living organisms perform vital functions. They are able to:
- Exchange matter and energy with their environment, processed and transformed by processes called metabolism. To maintain life activity, nutrition is essential.
- Create replicas or copies of themselves through the function of reproduction. This function requires the duplication of genetic information.
- Receive and respond to environmental information, a function of relation.
Living things are composed of molecules
Read MoreDNA, Cell Division, and Reproduction: Core Biological Processes
Understanding DNA: The Molecule of Life
DNA is the biomolecule that contains the genetic information for making proteins in the cell. This fundamental molecule dictates the characteristics and functions of all living organisms.
Chromosomes and Chromatin Structure
The genetic material within a cell is organized into structures called chromosomes. These are formed from a complex material known as chromatin, which is an association of DNA and proteins.
- When the cell is at rest, the chromatin is dispersed