General Biology 1 - PDF

GENERAL BIOLOGY 1 BIOLOGY - The study of living organisms. - Derived from the Greek words "bios" (life) & "logos" ("study"). The three major branches - Botany - zoology - Medical science  MEDICAL SCIENCE - it includes the study of several plants used in medicines. ...

GENERAL BIOLOGY 1 BIOLOGY - The study of living organisms. - Derived from the Greek words "bios" (life) & "logos" ("study"). The three major branches - Botany - zoology - Medical science  MEDICAL SCIENCE - it includes the study of several plants used in medicines.  BOTANY - it includes the study of plants.  ZOOLOGY - it includes the study of animals ARISTOTLE FATHER OF BIOLOGY  He is also regarded as the Father of Zoology. He started classification with two kingdoms animal and plantae. Aristotle's theory of biology is known as “Aristotle’s Biology” which describes metabolism, temperature, regulation, and embryogenesis.  CELL - the smallest unit that can live on its own and that makes up all living organisms and the tissues of the body DID YOU KNOW?  How many cells make up an average human being? - The average human being is composed of around 100 trillion individual cells!!! - It would take as many as 50 cells to cover the area of a dot on the letter “i” The smallest cells are SMALLEST CELL Bacteria-like mycoplasmas, which can be as small as 0.00004 inch (0.1 micrometer) in diameter. CELL THEORY ROBERT HOOKE (1665) - Cork specimen - Coined the word “cell"  ANTON VAN LEEUWENHOEK (1676) - “Animalcules”(an old term for microscopic organisms that includes bacteria, protozoans, & very small animals.  ROBERT BROWN (1831) - Inside the cell is a dark, dense spot which he termed “nucleus” (pl. Nuclei) FELIX DUJARDIN (1835) - State that cells were not hollow and described about the jellylike material in animal cells and termed it as “sarcode”. MATTHIAS SCHLEIDEN (1838) - concluded that all plant parts are made of cells  THEODOR SCHWANN (1839) - stated that all animal tissues are composed of cells RUDOLF VIRCHOW (1858) stated that all cell come from pre-existing cells  All living organisms are composed of cells. All cells are basically alike in structure and functions. The function of an organism as a whole is the result of the activities and interactions of constituents of the cell. 1. All living organisms are composed of one or more cells  2. The cell is the basic unit of life in all living things. 3. All cells come from pre-existing cells.  What is the importance of the postulates of cell theory? TYPES OF ORGANISMS BASED ON NUMBER OF CELLS Types of organisms based on number of cells: Unicellular Multicellular SIMILARITIES: Multicellular and unicellular organisms are similar in a way that they show almost all the life functions and processes such as reproduction and metabolism. Both unicellular and multicellular organisms have genetic materials embedded in them and they even contain similar organelles. TYPES OF CELLS BASED ON THE PRESENCE OF MEMBRANE-BOUND ORGANELLES Prokaryotic cells / prokaryotes - No true nucleus; has nucleoid - No membrane-bound organelles Eukaryotic cells / eukaryotes - Has true nucleus - Has membrane-bound organelles