Biology

Mica Piro Chapter 12: The Cell Cycle Most Cell Division Results in Genetically Identical Daughter Cells (12.1) Cellular Organization of the Genetic Material A cell?s endowment of DNA, its genetic information, is called its genome A prokaryotic genome is often a single DNA molecule Eukaryotic genomes usually consist of a number of DNA molecules All of this DNA has to be copied, or replicated, before the cell can divide to form genetically identical daughter cells, and then the 2 copies must be separated so that each daughter cell ends up with a complete genome The replication and distribution of so much DNA is manageable because the DNA molecules are packaged into structures called chromosomes, because they take up certain dyes used in microscopy

Mica Piro Chapter 10: Photosynthesis The Process That Feeds the Biosphere The conversion of light energy from the sun to chemical energy stored as sugar is called photosynthesis (occurs in algae, certain other unicellular eukaryotes, and some prokaryotes) Nourishes almost the entire living world directly or indirectly Organism acquires the organic compounds it uses for energy and carbon skeletons by one of 2 major modes: autotrophic nutrition or heterotrophic nutrition Autotrophs (?self-feeders?) sustain themselves without eating anything derived from other living beings Produce their organic molecules from CO2 and other inorganic raw materials obtained from the environment

Mica Piro Chapter 8: An Introduction to Metabolism An organism?s Metabolism Transforms Matter and Energy, Subject to the Laws of Thermodynamics (8.1) The totality of an organism?s chemical reactions is called metabolism It is an emergent property of life that arises from orderly interactions between molecules Organization of the Chemistry of Life into Metabolic Pathways A metabolic pathway begins with a specific molecule, which is then altered in a series of defined steps, resulting in a certain product Each step is catalyzed by a specific enzyme Metabolism as a whole manages the material and energy resources of the cell Some pathways release energy by breaking down complex molecules to simpler compounds?these degraditive processes are called catabolic pathways, or breakdown pathways

Mica Piro Chapter 6: A Tour of the Cell Biologists Use Microscopes and the Tools of Biochemistry to Study Cells (6.1) Microscopy Microscopes first used by Renaissance scientists are all light microscopes (LM) Visible light passed through the specimen and then through glass lenses Lenses refract/bend the light so the image of the specimen is magnified as it is projected into the eye or into a camera Magnification: ratio of an object?s image size to its real size LMs can magnify about 1,000 times the actual size Higher magnification = less detailed image Resolution: a measure of the clarity of the image?minimum distance 2 points can be separated and still be distinguished as separate points Contrast: the difference in brightness between the light and dark areas of an image