Summary of

Apuntes

Summary of Required Biological Concepts 1. Characteristics of Living Things Living organisms generally share the following features: * Cellular organization: Made of one or more cells. * Metabolism: Carry out chemical reactions to obtain and use energy. * Homeostasis: Maintain stable internal conditions. * Growth and development: Increase in size or complexity over time. * Reproduction: Produce offspring (asexually or sexually). * Response to stimuli: React to changes in their environment. * Evolution: Populations change over generations through natural selection. Are viruses alive? Viruses show some features of life (genetic material, evolution), but lack others (no cellular structure, no metabolism).
They can only reproduce inside a host cell, so they are generally considered non-living or “at the edge of life.” 2. Central Dogma of Molecular Biology The central dogma describes the flow of genetic information: DNA → RNA → Protein DNA Replication * Purpose: Copy DNA before cell division. * Enzymes: DNA polymerase, helicase, ligase. * Outcome: Two identical DNA molecules. Transcription (DNA → mRNA) * Location: * Prokaryotes: Cytoplasm * Eukaryotes: Nucleus * RNA polymerase ...