Biology

• Classification of Life


  domain -> kingdom -> phylum -> class -> order -> family -> genus -> species
• Organization of Life


  biosphere -> biome -> ecosystem -> community -> population -> organism -> organ system -> organ -> tissue -> cell
• Carbohydrates


  sugars and polymers of sugars, composed of a carbonyl (C=O) and hydroxide group (-OH)
• Monosaccharide


  single carbon skeleton
• Monosaccharide


  glucose, galactose, fructose
• Disaccharide


  two monosaccharides linked by a glycosidic bond
• Disaccharide


  maltose [glucose + glucose], sucrose [glucose + fructose]
• Polysaccharide


  several linked monosaccharides
• Polysaccharide


  starch, glycogen, cellulose
• Lipids


  hydrophobic nonpolar hydrocarbon molecules
• Fats


  consist of a glycerol connected to a fatty acid through an easier linkage
• Unsaturated Fat


  contains a cis-double bond in the fatty acid, liquid at room temperature
• Saturated Fat


  no fatty acid double bonds, solid at room temperature
• Trans Fat


  contains a trans-double bond in the fatty acid
• Phospholipids


  lipids with a phosphate group attached to the glycerol, has a hydrophobic and hydrophilic end, compose the cell membrane
• Steroids


  carbon skeleton is composed of four fused rings (e.g., cholesterol)
• Proteins


  consist of one or more chains of amino acids
• Amino Acid


  consists of an amino group and carboxyl group; there are 20 kinds of these
• Nucleic Acids


  polymers of nucleotides (e.g., DNA and RNA)
• Nucleotide


  contains a nitrogenous base (purines or pyrimidines), five-carbon sugar, and a phosphate group
• Purines


  cytosine (C), thymine (T), uracil (U)
• Pyrimidines


  adenine (A), guanine (G)
• Nucleus


  control center; houses genetic material
• Ribosome


  free-floating or attached; site of protein synthesis
• Smooth endoplasmic reticulum


  site of lipid synthesis and carbohydrate metabolism
• Rough endoplasmic reticulum


  synthesizer of membranes and proteins; has attached ribosomes
• Golgi apparatus


  modifier, sorter, and shipper of materials throughout the cell
• Lysosome


  digests celular materials
• Vacuoles


  storage sac for water and nutrients
• Mitochondrion


  site of cellular respiration
• Chloroplast


  site of photosynthesis
• Peroxisome


  producer of hydrogen peroxide and other enzymes involved in metabolic reactions
• Cytoplasms


  gel-like substance that fills the cell; site of most biochemical reactions
• Plasmodesmata


  pores between cell walls that allow intercellular communication
• Cell membrane


  semi-permeable layer that surrounds the cytoplasm
• Cell wall


  surrounds and protects the cell membrane
• Lysosome


  absent in plant cell but present in animal cell
• Centrosome with centriole


  absent in plant cell but present in animal cell
• Chloroplast


  present in plant cell but absent in animal cell
• Vacuole


  present (central and relatively larger) in plant cell and also present in animal cell