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BIOL 1107: Principles of Biology I Lab Manual (Burran and DesRochers)

  • Page ID
    • Lab 1: The Scientific Method
      The scientific method is central to the study of biology: it is a process of acquiring and verifying information through experimentation. The general steps of the scientific method are depicted in the figure below. The hypothesis, or suggested explanation for the observation, is the basis for setting up experiments. A good experimental design is essential to the scientific method. A few keys to good experimental design include effective use of controls, reproducibility, a large sample size, and
    • Lab 2: Taxonomy
      Because the diversity of life on Earth is so vast, biologists use a general system of classification and naming organisms (taxonomy) to track and organize species based on evolutionary relatedness. The broadest taxon is the domain; organisms belong to one of the three domains (Bacteria, Archaea, and Eukarya). Within the domains are increasingly specific taxa, ranging from kingdom and phylum all the way to genus and species. In this lab, you will be learning the basics of taxonomy and its usage.
    • Lab 3: Biological Molecules
      Biological systems are made up of four major classes of macromolecules: carbohydrates, lipids, proteins, and nucleic acids (nucleic acids will be covered separately later). In this lab, you will perform different tests to confirm the existence of each macromolecule. Then, you will use these techniques to identify the macromolecules present in the unknown mixture.
    • Lab 4: Microscopy
      A microscope is an instrument that magnifies an object so that it may be seen by the observer. In addition to magnification, microscopes also provide resolution. A combination of magnification and resolution is necessary to clearly view specimens under the microscope. In this lab, parts of the microscope will be reviewed. Students will learn the proper use and care of the microscope and observe samples from pond water.
    • Lab 5: Cells
      The cell theory states that all living things are composed of cells, which are the basic units of life, and that all cells arise from existing cells. In this course, we closely study both types of cells: prokaryotic and eukaryotic. There are vast differences between cell types but a few features are common to all cells. In this lab, bacterial, animal, and plant cells will be observed using the microscope. Students will draw what was visualized to record their observations.
    • Lab 6: Diffusion and Osmosis
      Diffusion is the process by which molecules spread from areas of high concentration to areas of low concentration. This movement, down the concentration gradient, continues until molecules are evenly distributed. Osmosis is a special type of diffusion: the diffusion of water through a semipermeable membrane. In this lab, you will observe both diffusion and osmosis through different surfaces.
    • Lab 7: Enzymes
      Enzymes are biological catalysts and are usually proteins. They greatly increase the rate of chemical reactions by lowering the activation energy, which is the energy required to start a reaction. The metabolism of a cell depends on enzymes functioning correctly. Enzymes are sensitive to environmental conditions. If the conditions deviate too much, enzymes may stop functioning. In this lab, you will examine the effects of environmental changes on enzymatic activity using the enzyme catalase.
    • Lab 8: Cell Respiration and Photosynthesis
      Photosynthesis fuels ecosystems and replenishes the Earth's atmosphere with oxygen. Like all enzyme-driven reactions, the rate of photosynthesis can be measured by either the disappearance of the substrate or the accumulation of the products. In this investigation, you will use a system that measures the accumulation of oxygen in the leaf and explore a case study of cellular respiration failure.
    • Lab 9: Mitosis and Meiosis
      All cells come from preexisting cells and eukaryotic cells must undergo mitosis in order to form new cells. The replication of a cell is part of the overall cell cycle which is composed of interphase and M phase (mitotic phase). Failure of chromosomes to separate during mitosis or meiosis will result in an incorrect number of chromosomes in daughter cells, known as nondisjunction. In this lab, you will observe mitosis taking place as well as explore nondisjunction events during meiosis.
    • Lab 10: Inheritance
      In diploid organisms, each body cell (or 'somatic cell') contains two copies of the genome. Each somatic cell contains two copies of each chromosome and two copies of each gene. The exceptions to this rule are the sex chromosomes that determine sex in a species. The paired chromosomes that are not involved in sex determination are called autosomes, to distinguish them from the sex chromosomes. The different forms of a gene that are found at a specific point on chromosome are known as alleles.
    • Lab 11: Nucleic Acids
      In 1953, James Watson and Francis Crick established the structure of deoxyribonucleic acid (DNA). The structure is a double helix, which is like a twisted ladder. The sides of the ladder are made of alternating sugar (deoxyribose) and phosphate molecules. The rungs of the ladder are pairs of 4 types of nitrogen bases. Two of the bases are purines - adenine and guanine. The pyrimidines are thymine and cytosine. The bases are known by their coded letters A, G, T, C.
    • Lab 12: Biotechnology
      Gel electrophoresis is a procedure that separates molecules on the basis of their rate of movement through a gel under the influence of an electrical field. When forensic scientists try to determine the source of DNA found at a crime scene, they can run the DNA samples from the crime scene and the suspects side by side on a gel and compare them to determine if the banding patterns are the same. Today’s lab illustrates the process of gel electrophoresis with dyes instead of with DNA.
    • Lab 13: Evolution
      While in the Galapagos Islands, Darwin noticed that the beaks of various finches were different lengths, shapes, and sizes. The differences he observed led him to several of his most important ideas about the mechanisms and processes that are responsible for descent with modification, including natural selection.