Conceptos Generales de Biología Humana

General Concepts

• Biología humana is the study of living organisms, including their structures, functions, origins, and evolutionary history, and their interactions with the abiotic environment.
• Key characteristics of living beings are organization, irritability, metabolism, movement, and homeostasis, and reproduction.

Characteristics of Living Beings

• Organization: Living organisms are complex systems composed of interconnected elements, following specific principles of organization (e.g., cells).
• Irritability: Living organisms respond to environmental stimuli.
• Metabolism: Essential for life's functions, involving processes of synthesis (anabolism) and breakdown or degradation (catabolism).
• Movement: Includes the movement of cells, substances, or the entire organism itself.
• Homeostasis: Mechanisms that maintain internal stability in organisms, despite changes in the environment.
• Reproduction: Key process for perpetuating species through asexual or sexual reproduction, ensuring the passing of genetic material.
• Adaptation Living beings can adapt from individual level or species level in response to their environment. This adaptiation may not be based on genetics or it may be transmitted to progeny.
• Evolution: The process of change in populations over time, where populations change and transform their characteristic through generations.

Cell Theory

• Cells are the structural and functional units of living organisms.
• Cells arise from preexisting cells.
• Cells contain genetic information, necessary for performing all functions and processes of living beings.

Levels of Organization

• Chemical level (atoms, molecules).
• Cellular level (cells).
• Tissue level (tissues formed by cells).
• Organ level (organs formed by tissues).
• Organ system level (organ systems formed by organs).
• Organism level (organism).
• Population level (population made of individuals from same species).
• Community level (community formed by various interacting populations).
• Ecosystem level (ecosystem formed by organism and its abiotic environment).
• Biosphere level (all the ecosystems of the earth).