Introduction to Biology & History of Science

Introduction to Biology for Health Sciences

• Biology is the study of life, derived from the Greek words "bios" (life) and "logus" (study).
• Biology encompasses the origin, history, structure, function, identification, classification, distribution, development, inheritance, and significance of living things, including their interactions with the environment.

How Science Was Developed

• Andreas Vesalius (1543) was an anatomist who studied the human body and created "The Fabrica" with detailed anatomical illustrations and is now known as the Father of Modern Anatomy.
• William Harvey (1628) was a physician who identified the complete blood circulation in the human body through experiments.
• Marcello Malpighi (1661) made key contributions to physiology, medicine, and embryology and is regarded as one of the founders of microscopic anatomy.
• Robert Hooke (1665) discovered the cell, which is the basic unit of life, and published "Micrographia," showing sketches of natural objects under a microscope.
• Anton van Leeuwenhoek (1674) invented the microscope, discovered sperm, and concluded that fertilization occurs when sperm penetrates the egg and is the Father of Microbiology.
• Theodor Schwann, Matthias Schleiden, and Rudolf Virchow are famous for their Cell Theory that states all living things are made of cells; Cells are the basic units of structure and function in living things; and Living cells come only from other living cells.

The Scientific Method

• Observation involves using senses to identify a problem from observations or gathered information.
• Hypothesis formulation involves creating a testable explanation or tentative explanation for an event, based on a scientific theory.
• Experimentation involves conducting experiments to test hypotheses. Hypotheses can be disproven but not definitively proven.
• Analysis and interpretation of data and results require collecting and interpreting data using graphs and tables to accept or reject hypotheses.
• Generalization or formulation of a conclusion involves forming a theory based on analyzed data, supported by experimental evidence.

Branches of Biology

• Cytology is the study of cells.
• Histology studies tissues.
• Organology studies organs.
• Anatomy involves the dissection of body parts.
• Physiology examines the functions of living organisms and their parts.
• Embryology studies the development of the embryo.
• Genetics studies heredity.
• Pathology studies diseases.
• Ecology examines interactions and relationships within an ecosystem.
• Evolution is about the origin of species.
• Paleontology studies fossils and evidence of past life.
• Systematics deals with classification and phylogeny.
• Taxonomy is a classification.
• Nomenclature deals with the naming and assigning of scientific name.
• Biogeography is concerned with the distribution of living things.
• Ontogeny studies the developmental history of an individual.
• Phylogeny studies the ancestral history of an individual.
• Limnology is the study of freshwater habitats.
• Oceanography studies marine habitats.
• Microbiology studies microorganisms.
• Bacteriology studies bacteria.
• Parasitology studies parasites.
• Virology studies viruses.
• Protozoology studies protozoans.
• Phycology studies algae.
• Mycology studies fungi.
• Botany (Phytology) studies plants.
• Bryology studies mosses.
• Zoology studies animals.
• Helminthology studies worms.
• Carcinology studies crustaceans.
• Malacology studies mollusks.
• Entomology studies insects.
• Ichthyology studies fishes.
• Herpetology studies reptiles and amphibians.
• Ornithology studies birds.
• Mammalogy studies mammals.

Unifying Theories of Biology

• The Cell Theory states that all organisms are made of cells, which are the basic unit of life.
• The Biogenesis theory, proposed by Rudolf Virchow and supported by Louis Pasteur, states that life can only come from life.

Characteristics of Living Things

• Metabolism encompasses all chemical and energy transformations in cells and can be anabolic (building up) or catabolic (breaking down).
• Growth refers to an increase in size, directed by genes.
• Irritability is the ability to react to environmental changes or stimuli.
• Reproduction is the ability to produce offspring, either asexually or sexually, passing on DNA and genes.
• Adaptation is the fit of organisms to their environment, resulting from evolution by natural selection.
• Organization refers to the specific arrangement of parts in a living organism.

Assimilation and Definite Chemical Composition

• Assimilation is the process of converting non-living inorganic and organic molecules into a living cell.
• Living things consist of inorganic molecules (water, salts, minerals, gases) and organic molecules (carbohydrates, lipids, proteins, nucleic acids).