Genetic Alterations: A Comprehensive Look at DNA Changes
Gene Mutations: Types and Impacts
Gene mutations alter the nucleotide sequence of a single gene.
Base Substitutions
Base substitutions account for approximately 20% of all mutations. They involve the replacement of one DNA base with another, affecting only a single nucleotide.
Due to the degenerate nature of the genetic code, a mutated triplet may still encode the same amino acid; this is known as a silent mutation. If the new triplet codes for a different amino acid, it can have serious consequences,
Read MoreEssential Organelles: Structures & Functions of Eukaryotic Cells
Key Organelles and Structures of Eukaryotic Cells
The Nucleolus
The nucleolus is a region within the nucleus, considered an organelle. Its primary function is the production and assembly of ribosomal components.
The Cell Nucleus
The cell nucleus is a membranous organelle found in eukaryotic cells. It contains most of the cell’s genetic material, organized into multiple long, linear DNA molecules complexed with various proteins like histones to form chromosomes. The collection of genes on these chromosomes
Read MoreHuman Body Systems: Nervous System and Neurons Explained
The Body’s Interaction Process
The human body constantly interacts with its internal and external environments to maintain stability and function. This complex process involves several key objectives:
- Adapting the body to changing conditions in both the internal and external environment.
- Connecting and coordinating different parts of our body to ensure they work together seamlessly.
Homeostasis: Maintaining Body Stability
Homeostatic processes are crucial for maintaining the body’s internal stability
Read MoreFood Microbiology Essentials: Safety, Preservation, Nutrition
What is Food Microbiology?
Food microbiology is the study of microorganisms (bacteria, yeasts, molds, and viruses) that grow in or contaminate food. It focuses on how microbes affect food safety, preservation, fermentation, and spoilage.
Significance of Food Microbiology
- Food Safety: Helps identify and control harmful microbes like Salmonella or E. coli.
- Food Preservation: Understands how to use methods like refrigeration or fermentation to control microbial growth.
- Food Production: Supports beneficial
Human Body Systems: Anatomy & Physiology Essentials
Chapter 17: The Special Senses
Olfaction (Sense of Smell)
- Receptors: Olfactory receptor cells in the nasal epithelium.
- Pathway: Odorants → Olfactory nerves → Olfactory bulb → Olfactory tract → Temporal Lobe.
- Adaptation: Rapid; sensitivity decreases quickly.
Gustation (Sense of Taste)
- Taste Buds: Located on papillae; contain gustatory receptor cells.
- Primary Tastes: Sweet, sour, salty, bitter, umami.
- Pathway: Taste buds → Cranial Nerves VII, IX, X → Medulla → Thalamus → Gustatory Cortex.
Vision
- Eyeball
Biological Principles: Life Cycles, Reproduction, Evolution
Biological Processes and Concepts
Fungi Life Cycle
- Haploid (n): Single set of chromosomes.
- Plasmogamy: Haploid cells from two different mycelia fuse to form a heterokaryotic cell (two or more nuclei).
- Dikaryotic (n + n): Cell containing two distinct haploid nuclei.
- Karyogamy: The nuclei fuse to form a diploid (2n) zygote.
- Diploid (2n): Double set of chromosomes.
- Meiosis: Haploid (1n) spores are formed.
Plant Life Cycle
- Alternation of two generations.
- Two multicellular phases: haploid (n) and diploid (2n).