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- https://bio.libretexts.org/Learning_Objects/Laboratory_Experiments/General_Biology_Labs/BIOL_1107%3A_Principles_of_Biology_I_Lab_Manual_(Burran_and_DesRochers)/01%3A_Labs/1.13%3A_EvolutionWhile 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 a...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.
- https://bio.libretexts.org/Courses/Sacramento_City_College/BIOL_342%3A_The_New_Plagues_-_New_and_Ancient_Infectious_Diseases_Threatening_World_Health_(Hughes)/02%3A_Week_2/02%3A_Disease_and_Epidemiology_(Part_A)/2.01%3A_Tracking_Infectious_DiseasesSome important researchers, such as Florence Nightingale, subscribed to the miasma hypothesis. The transition to acceptance of the germ theory during the 19th century provided a solid mechanistic grou...Some important researchers, such as Florence Nightingale, subscribed to the miasma hypothesis. The transition to acceptance of the germ theory during the 19th century provided a solid mechanistic grounding to the study of disease patterns. The studies of 19th century physicians and researchers such as John Snow, Florence Nightingale, Ignaz Semmelweis, Joseph Lister, Robert Koch, Louis Pasteur, and others sowed the seeds of modern epidemiology.
- https://bio.libretexts.org/Learning_Objects/Laboratory_Experiments/General_Biology_Labs/BIOL_1108%3A_Principles_of_Biology_II_Lab_Manual_(Burran_and_DesRochers)/Lab_05%3A_Sensory_SystemsIn this lab, we will explore the anatomy & physiology used for interpreting the environment both within and outside our bodies. The essential component is neurons, the major functional cells in nervou...In this lab, we will explore the anatomy & physiology used for interpreting the environment both within and outside our bodies. The essential component is neurons, the major functional cells in nervous tissue. In many sensory organs, additional cells and tissues will contribute to the process of signal transduction. The major sensory organs can be grouped based on various characteristics, i.e. what type of matter or energy they detect and subsequently ‘transduce’ to produce our perceptions.
- https://bio.libretexts.org/Learning_Objects/Laboratory_Experiments/Microbiology_Labs/Microbiology_for_Allied_Health_Students%3A_Lab_Manual/3.04%3A_CatalaseCatalase is an enzyme that breaks hydrogen peroxide into water and oxygen. Hydrogen peroxide is a common byproduct of metabolic reactions occurring in an environment where water and oxygen are present...Catalase is an enzyme that breaks hydrogen peroxide into water and oxygen. Hydrogen peroxide is a common byproduct of metabolic reactions occurring in an environment where water and oxygen are present, but it is toxic to cells. Therefore, most organisms that survive in the presence of oxygen contain enzymes to degrade the hydrogen peroxide.
- https://bio.libretexts.org/Learning_Objects/Laboratory_Experiments/Microbiology_Labs/Microbiology_for_Allied_Health_Students%3A_Lab_Manual/3.01%3A_Carbohydrate_FermentationDuring fermentation most bacteria convert carbohydrates into organic acids, with or without the production of gas. One can test for this by adding a pH indicator and an inverted tube (a Durham tube) t...During fermentation most bacteria convert carbohydrates into organic acids, with or without the production of gas. One can test for this by adding a pH indicator and an inverted tube (a Durham tube) to the culture medium. We will use phenol red as the pH indicator. If acid is produced the phenol red will turn yellow (pH below 6.8). Any gas produced will form a bubble in the inverted tube.
- https://bio.libretexts.org/Learning_Objects/Laboratory_Experiments/General_Biology_Labs/BIOL_1108%3A_Principles_of_Biology_II_Lab_Manual_(Burran_and_DesRochers)
- https://bio.libretexts.org/Learning_Objects/Laboratory_Experiments/Microbiology_Labs/Microbiology_for_Allied_Health_Students%3A_Lab_Manual/3.05%3A_Motility_AgarBecause the flagellar staining procedure often produces poor results in the hands of novices, other tests for motility (and the presence of flagella) have been developed. One type of test involves usi...Because the flagellar staining procedure often produces poor results in the hands of novices, other tests for motility (and the presence of flagella) have been developed. One type of test involves using a semi-solid medium that allows motile bacteria to penetrate.
- https://bio.libretexts.org/Learning_Objects/Laboratory_Experiments/General_Biology_Labs/BIOL_1107%3A_Principles_of_Biology_I_Lab_Manual_(Burran_and_DesRochers)/01%3A_Labs/1.07%3A_EnzymesEnzymes 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...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.
- https://bio.libretexts.org/Learning_Objects/Laboratory_Experiments/General_Biology_Labs/BIOL_1107%3A_Principles_of_Biology_I_Lab_Manual_(Burran_and_DesRochers)/01%3A_Labs/1.11%3A_Nucleic_AcidsIn 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 a...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.
- https://bio.libretexts.org/Learning_Objects/Laboratory_Experiments/Microbiology_Labs/Microbiology_for_Allied_Health_Students%3A_Lab_Manual/3.13%3A_Levine_EMB_AgarLevine EMB (eosin methylene blue) agar is an example of a selective and differential medium. This means that only some bacteria will grow on this agar and that the appearance of those that do grow wil...Levine EMB (eosin methylene blue) agar is an example of a selective and differential medium. This means that only some bacteria will grow on this agar and that the appearance of those that do grow will be different. In particular, EMB agar inhibits the growth of Gram-positive bacteria and helps differentiate some of the Gram-negative rods.
- https://bio.libretexts.org/Learning_Objects/Laboratory_Experiments/General_Biology_Labs/BIOL_1107%3A_Principles_of_Biology_I_Lab_Manual_(Burran_and_DesRochers)/01%3A_Labs/1.08%3A_Cell_Respiration_and_PhotosynthesisPhotosynthesis 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 subs...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.
