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    Human Biology

    MIC Calculation & Dilution series

    The MIC of penicillin for Staphylococcus epidermis was determined to be in tube #5. The starting concentration was 1000g/ml in tube #1 and a 5-fold dilution was performed. What is the MIC? Show how you would do the dilution series?

    Determining Neuronal Activity

    Since at any moment a neuron is likely to have thousands of neurons releasing neurotransmitters at its surface, how is neuronal activity (to fire or not to fire) determined?

    EPSP/IPSP

    Please answer the following: (a) Explain the difference between an EPSP and an IPSP. (b) What specifically determines whether an EPSP or IPSP will be generated at the postsynaptic membrane?

    Action Potential Generation

    This job describes the events that must occur to generate an action potential (AP). It then relates the sequence of changes in permeability to changes in the ion channels and explains why the AP is an all-or-none phenomenon.

    Concentration of the Protein in the Serum

    2.00 mL serum sample is analyzed for protein by the modified Kjeldahl method. The sample is digested, the ammonia is distilled into boric acid solution, and 15.0 mL of standard HCl is required for titration of the ammonium borate. The HCl is standardized by treating 0.330g pure (NH3)2SO4 in the same manner. If 33.3 mL acid is re

    Calculate osmolar clearance and free water clearance

    A 35-year-old female complains to her doctor that she is suffering from frequent urination. Her resting blood pressure and heart rate are 120/80 and 72, respectively. Her plasma creatinine is 0.85 mg/dl, urine flow is 5 ml/min, and urine osmolarity is 190 mOsm/l. Her plasma osmolarity is 290 mOsm/l. Calculate her osmolar clea

    MHC uniqueness of individuals

    Find the correct answer: The uniqueness of an individual is defined in part by the a. Type of antibodies produced by that individual b. Antigens to which the individual can respond c. Ability to produce T cells after passage through the thymus d. MHC proteins on the surfaces of the individual's cells.

    Integumentary homeostasis

    You go to the beach to swim on an extremely hot, sunny summer afternoon. This job describes two ways in which your integumentary system acts to preserve homeostasis during your outing.

    Neurobiology questions

    1. Two types of GABA receptors have been identified. The GABA(a) receptor is an ion channel permeable to CL-; and the GABA(b) receptor is a G-protein-couple receptor (activates a second messenger cascadein the postsynaptic cell) which causes K+ selective channels to open. What effect would the activation of GABA(b) receptors hav

    Volume & Concentration Problem is asssessed.

    I have 100mls of an antibiotic stock solution at a concentration of 6mg/ml. I would like a final volume of 10mls of the antibiotic at a concentration of 1.5mg/ml. How much of the stock solution do I need to obtain this?

    Serial Dilutions are explained.

    You are given a milk sample that Mr. Milkman claims contains 3.8 x 10^8 CFU/ml. He claims this is within the limit of acceptable CFU/ml for Grade A milk. Diagram a procedure he could use to determine the CFU/ml and information pertinent to proving or disproving Mr. Milkman's claim. Is the milk within the acceptable limit?

    Auditory System

    Consider two hearing-impaired persons. One is deaf in the left ear but has normal hearing in the right ear. The second cannot hear frequencies above 1 kHz in either ear, but has normal hearing in both ears for lower frequencies. What problems would these two persons have with such everyday auditory tasks as localizing sound in s

    Dilution Series for Liquid Culture of Staphylococcus Aureus

    If you had a liquid culture of Staphylococcus aureus and transferred 2ml to test tube "R", which contains 8ml of nutrient broth, what would be the final dilution (in simplest terms) of the culture in test tube "R"? From the culture in "R" make a 1:15 dilution in tube "S". What is the final dilution of the culture in tube "S"?

    Dilution Series

    I am looking for a detailed solution and explanation. I give you 10mls of an overnight culture of Micrococcus luteus at a concentration of 4.7 x 10^7 CFU/ml. Diagram a dilution series by using tubes containing 9ml nutrient broth (NB) and fixed-volume 1ml pipettes (won't measure any more or less than 1ml).

    Dilution Series

    Perform a 2-fold serial dilution using 4 tubes containing 1ml of NB each and a 20ml broth culture of Bacillus subtilis; use the same B. subtilis culture and perform a 2-fold serial dilution using 4 tubes containing 2ml of NB each; repeat in a similar fashion using 4 tubes containing 0.5ml each.

    Dilution Series

    I give you a very expensive strain of E. coli containing 10^12 CFU/ml and tell you that I need exactly 10ml of the same E. coli culture at a concentration of 10^4 CFU/ml (I don't want any excess culture). Using a dilution series, how would you get the correct concentration and volume of bacteria? Make this a realistic scenario.

    Reproductive strategies, the human population, population growth

    Identify the two most extreme types of reproductive strategies and make a distinction between the traits that would characterize these extremes. Give an example of an organism that illustrates each strategy. Identify the major problems anticipated with the increase in the human population in the 21st century and explain why i

    Flow Chart to Represent the Organizational Relationships

    Draw a flow chart to represent the organizational relationships between the following terms from the most inclusive to the least inclusive: ecosystem, population, species, community, and biosphere. Please provide a brief definition of each.

    Define and Identify the Relationship with Stress

    I started to answer these could you please help me ? C. Define and identify the relationship that the following have with stress: Epinephrine: A hormone secreted by the adrenal medulla. Epinephrine plays a central role in the short-term response to stress reaction. It is the physiological response to threatening excitemen

    The combination of atoms in molecules

    The combination of atoms in molecules depends in large measure on the a) Number of neutrons b) Placement of electrons in the shells c) Presence of organic matter in the environment d) Proton configuration of the nucleus

    Protein and Elements in Solution

    Can you please confirm my choices for the below question? 1. A denatured protein is one that a. Has lost its three dimensional structure. b. Has reverted to a carbohydrate. c. Lacks amino acids. d. Lacks covalent bonds. My choice is (D) 2. Ions and atoms of an element differ in the a. Number of electrons they posse

    IS THIS SCIENCE?

    1. IS THIS SCIENCE? Promotional materials for a sports drink say that "water is not enough" for people who are exercising and that it's important to instead consume a liquid that contains flavoring, carbohydrates, potassium and sodium. Do you think that consuming a sports drink after exercise can help maintain homeotasis? E

    Topic: Smoking( see full description)

    Topic: Smoking The topic must relate to the human body and contain in the following: 1. Introduction stating issue/problem and opinion/stance on this issue. 2. Main body- history/background supporting documentation, opposing Opinions, pros/cons. 3. Summary 4. Bibliography (at le

    Muscle biopsies and functions of the cytoskeleton

    3. If muscle biopsies (sample of tissue) were taken from the legs of a world-class marathon runner and a typical couch potato, which would you expect to have higher density of mitochondria? Why? How would the density of mitochondria in a muscle biopsy from the biceps of a weight lifter compare with those of the runner and th

    Provide solution

    Consider the consequences if a large meteor were to impact with Earth. What characteristics would be essential for survival ? What types of characteristics would be detrimental? What would have to be preserved in order to establish a diversity of life? What are the implications on evolution? What is your predic

    'What would the world be like if solid water (ice) was denser than liquid water?

    One of the science fiction magazines is having a call for conference topics. You decide to submit the following topic: ''what would the world be like if solid water (ice) was denser than liquid water?" Create a brief synopsis and include a brief discussion on the following issues: how you think the world would be diffe

    Role of fungi in forests

    If all the fungi were removed from our Pacific Northwest Forests how would that change our forests? (brief but thorough)

    Roles of energy in biology

    1. Relate energy concepts to living things - 1 paragraph. 2. Why energy is not recycled in an environment ? 1 paragraph . 3. Why an ecosystem can only support a finite population of species. 1 paragraph. 4. Discuss human's excessive consumption of energy and its implications upon future generations