Microbiology Essay

1597 words - 7 pages

Chapter 17 Study Guide

We will focus on only a few key concepts from this chapter. You should already be familiar with many of these concepts from other courses.

1. It is believed that the first organisms appeared on Earth around 3.8 billion years ago. What evidence do each of the following for this occurrence?
• Stromatolites

-the earliest forms of lfe for which we have clear fossil evidence
-a bulbous mass of sedimentary layers of limestone accreted by microbes over years
-within the outer layers, microbes grow as a microbial mat (sort of like a biofilm)
-outer laters of mat contain oxygenic phototrips that exude bubbles of oxygen
-a few mm below surface, red light ...view middle of the document...

View the animation “Phylogenetic trees” to refresh your memory about cladograms. These trees make the assumption that the rate of nucleotide change is constant. For each of the following explain why this is not always true.
• sequences that code for functional genes change slower
• genes in rapidly replicating organisms change faster
• different environments result in different selective pressur

-functional sequences change slower→ why?
-functinal sequences: code for structures: ribosomes→ differ because theyre more important and the organism can’t survive if they change

-selective pressure: genes that provide desireable genes

phylogenetic tree: estimates the relative amounts of evolutionary divergence between the sequences
-if divergence rate over time or mutation rate is the same for all sequences compared, then divergence data can be used to infer the length of time since two species shared a common ancestor

-Maximum Parsimony: evolutionary distances are computed for all pairs of taxa based on the numbers of nucleotide or amino acid substitution between them
- a proposed common ancestor is reconstructed, all possible trees comparing relative time of divergence from the common ancestor are computed
-the best fit tree is the one with the fewest mutations to fit the fata

Maximum Liklihood: for each possible tree, the likelihood that such a tree would have produced the observed DNA sequences
-the probability of given mutations is based on complex statisrical calculations
-require large amouns of computation but obtain the most info from the data

3. Compare the three domains of life. Traditionally trees of life have shown the Domain Bacteria branching off first (Figure 17.21), then the Arachea branching off later from the lineage leading to the Domain Eukarya. Use the information summarized in Table 17.2 to explain the evidence that supports this hypothesis.

-archaea are roughly as distant from bacteria as eukaryotes
-thee domans → Woese

-root of the tree: compare a pair of homologous genes wth one organims, homologs that diverged from a common ancestral gene and acquired distant functions

-most phylogenetic data so far indicate a root between Bacteria and the common ancestor of Archaea and Eukarya
-thus Bacteria diverged before Archaea and Eukarya diverged from each other

-All domains have distinctive traits absent of scarce in the other two

Eukaryotes: have nucleus and complex membranous organelles
-mitrochondira and chloroplasts which evolved from internalized baceria
-bacteria and archaea have no nucleus and have relatively simple intracellular membranes
-size is limited by diffusion across the cell membrane with occasionall exceptions
-the larger size and complexity of eukaryotic cells generally require the most high-powered sources of energy such as aerobic respiration and oxygenetic photosynthesis although some protists conduct fermentation
-prokaryores have a wider...

Other Papers Like Microbiology

Microbiology Essay

2628 words - 11 pages Anti-Microbials and their source Microorganism | Drug + additional notes | Bacillus subtilis | Bacitracin: G(+), topical, nephrotoxic*doxycycline can be used for chronic renal disease*minocycline for acne & meningococcemia | Bacillus polymyxa | Polymyxin | Streptomyces nodosus | Amphotericin B | Streptomyces noursei | Nystatin | Streptomyces lincolnensis | Lincosamine | Streptomyces orientalis | Vancomycin: for MRSA

Microbiology Essay

1347 words - 6 pages Name and course section: LeKesha Hinds Title: Bacterial Morphology- Lab #2 Purpose: Being able to observe morphologies by preparing wet mount slides and learning direct and indirect staining techniques. Procedure: First, set up the microscope. View the prepared slides of bacterial morphology. Use each morphological type as a comparative tool for the remainder of the exercise. Disinfect your work area with a 10%-bleach solution using the

Microbiology

1067 words - 5 pages Laporan Praktikum Tanggal Praktikum: Kamis, 22 Maret 2012 Mikrobiologi Pangan PJ Praktikum : Lukie Trianawati, STP, Msi. Asisten : Mariska Pratami P, A.Md PENGGUNAAN MIKROSKOP (Pengamatan Morfologi Kapang dan Khamir Menggunakan Mikroskop) Kelompok 2/BP1 Putra Mahardiman J3E111078 Dian Mawarni J3E111027 Dina Crownia J3E111087 Niken Indah C. J3E111081 Rosi Rizki R. J3E111034 SUPERVISOR JAMINAN MUTU

Microbiology Lab Report

543 words - 3 pages tube? E.coli and Proteus H. Did your direct and indirect observations of motility show the same results? If they didn’t, why do you think that may have been the case? Both results showed that the E. coli and Proteus were motile while the S. epidermidis was nonmotile. No they were not the same results. Direct observation they were moving. References Van Meter, K. C., Van Meter, W. G., & Hubert, R. J. (2010). Microbiology for the Healthcare Professional (1st ed.). [https://online.vitalsource.com/#/books/978-0-323-04594-0/cfi/0]. Retrieved from https://online.vitalsource.com/#/?return=/books

Microbiology Exam 3

1913 words - 8 pages Microbiology Exam 3 Amber E. Baity Excelsior College 1.Blood isolated from an emergency room patient contains antibodies against the measles virus. Please explain whether or not the patient should be quarantined immediately because they are infected with the measles virus and why? What are the other plausible explanations for anti-measles antibodies in the patient’s blood? Though this could appear a critical situation, this patient does

Microbiology Lab-Bacterial Growth and Controlling It

1342 words - 6 pages for the microorganisms to use for growth. H. When you use sources, include all in-text citations and references in APA format. References: Alonzo, Cynthia. (n.d.). Aseptic Technique & Culture Microbes. In Microbiology – MLT1 (pp.84-99) Englewood, CO: Hands-On Labs, Inc. Betsy, T., & Keogh, J. (2005). Microbiology Demystified. Blacklick, OH, USA: McGraw-Hill Professional Publishing.

Microbiology Task 12 Yeast, Molds and Fungi

840 words - 4 pages grow at 37oC) and morphologic forms (e.g., yeasts / hyphae) that facilitate their multiplication within the host. For example, the fungi that colonize skin, hairs, and nails have enzymes that digest keratin. Candida albicans exists in a unicellular yeast like morphology, but when it invades tissues it becomes filamentous; also, the systemic fungi histoplasmas are molds in nature and change to a unicellular morphology when they cause disease and growth promoting disease in the host (Gladwin, & Trattler, 2011). References Gladwin, M., & Trattler, B. (2011). Clinical Microbiology made ridiculously simple

Medical Microbiology

2318 words - 10 pages A Case Of Non-Hodgkins Lymphoma A case was presented of a possible infection with non-hodgkins lymphoma. The patient is a 60 year old man that presented symptoms petering to the development of a follicular lymphoma. The patient has been suffering from colds and fevers more frequently in the past weeks and upon physical examination swelling was observed under his left armpit. Preliminary diagnosis suggests follicular lymphoma which is indicative

Brandy Distillation Microbiology

990 words - 4 pages Brandy Brandy is an alcoholic beverage produced by the distillation of wine with an alcohol content of between 35 – 60% by volume. It is mostly served as an after-dinner drink, but also popular in bars and nightclubs in many countries. It can also be produced by fruits other than grapes but is sold under different names, such as eaux-de-vie in France and schnapps in Germany. There are varying requirements held by countries in order to

Global and Chinese Food Microbiology and Safety Equipment Industry, 2009-2019 Market Research Report

859 words - 4 pages Market Research Report on Global and Chinese Food Microbiology and Safety Equipment Industry, 2009-2019 is a professional and in-depth market survey on Global and Chinese Food Microbiology and Safety Equipment industry. The report firstly reviews the basic information of Food Microbiology and Safety Equipment including its classification, application and manufacturing technology; The report then explores global and Chinas top manufacturers of

Emerging and Reemerging Diseases Module 8-Microbiology

1381 words - 6 pages Module 08 Homework Assignment 1. Discuss the four (4) different classifications of emerging and re-emerging infectious diseases and give examples of diseases for each class. How do these classes differ from the three groups classified by the National Institute of Allergy and Infectious diseases (NIAID)? There are four major groups of emerging and reemerging diseases which are classified as newly emerging, reemerging, new manifestations

Related Essays

Microbiology Essay 935 Words

935 words - 4 pages Diagnosis of an Infected Patient: Microbiology Paper Bio 212 18 January 2015 Diagnosis of an Infected Patient After collecting a sputum sample from a patient that is suspected or may be infected with a bacterium from one of the following genera: Escherichia, Mycoplasma or Bacillus; Each bacteria listed should be isolated by utilizing each of the various staining techniques. The best staining techniques to use is the Gram stain or the

Microbiology Essay 576 Words

576 words - 3 pages pattern of the colonies that grew from your S. epidermidis. S. epidermidis colonies are 1 to 2 mm in length that is white in color and slightly raised. The bacteria cells are arranged in clusters (Staphylococci). References Gladwin, M., & Trattler, B. (2011). Clinical Microbiology made ridiculously simple Ramakrishnan, S., & Sulochana, K. N. (2012). Sankara Nethraylaya's manual of medical laboratory techniques. New Dehli, India: Jaypee Brothers Medical Publishers.

Microbiology Essay 576 Words

576 words - 3 pages pattern of the colonies that grew from your S. epidermidis. S. epidermidis colonies are 1 to 2 mm in length that is white in color and slightly raised. The bacteria cells are arranged in clusters (Staphylococci). References Gladwin, M., & Trattler, B. (2011). Clinical Microbiology made ridiculously simple Ramakrishnan, S., & Sulochana, K. N. (2012). Sankara Nethraylaya's manual of medical laboratory techniques. New Dehli, India: Jaypee Brothers Medical Publishers.

Microbiology Essay 4585 Words

4585 words - 19 pages degradation of organic materials u. Live on land 28. Helminths v. Roundworms w. Tapeworms x. Parasitic 4. What are the three domains of living organisms and what differentiates them? l. Bacteria, Archaea, Eukarya 5. Explain the importance of observations made by Hooke and van Leeuwenhoek. m. Microbiology was found in 1674 n. Early