BI 101 Online Lab Procedure

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BI 101 Online Lab Procedure
Lab 3: Isle Royale
Learning Objectives:
By the end of this lab you will be able to: ● Describe carrying capacity and how it relates to logistic growth. ● Discuss predator-prey cycles. ● Understand how changes to growing season can impact all organisms in a habitat.
Additional resources needed:
The following resources are located in the Week 3 “Research and Report” section of the Moodle course. ● Lab 3 Report: Use the report to answer some critical thinking questions and describe your
experience using the software. When complete, submit through the submission page in Moodle.
Introduction:
This lab requires you to have registered your SimUText software that you downloaded at the beginning of the term. Be sure to do this early in the week if you have not already done so. If you have trouble getting registered, it is imperative that you resolve any issues with the registration number provided in the ‘Technology Resources’ section of the course Moodle page before Friday afternoon since SimUText customer support may only available during normal business hours. ​Late submissions will not be accepted due to technical difficulties or lack of planning with the software registration​.
Procedure:
1. Log onto the SimUText software. Select “LAB: Isle Royale”.
2. There are 6 sections in the simulation. You will work through section 1 – 3 in order by using the “Next Page” navigation button at the bottom of the simulation screen. In order to receive full credit for this lab you must complete all the practice the first three sections.
3. Work through the assigned sections and answer questions in the Lab Report as you go. Don’t get too hung up on the math presented in the simulation, you are not required to have a detailed understanding of the logistic growth equation, just a strong understanding of logistical growth. You may find it helpful to review the practice module on population growth models if you are struggling with the concept.
4. Section 4, “An Extended Exploration: The t-Test” is beyond the scope of this class, and can be extremely challenging without prior knowledge of statistics. It is not required that you do this exercise.
5. Section 5, “Isle Royale Playground” does not have any specific questions or connection to questions in the lab report, but provides an opportunity to explore other questions you may have regarding this activity, so feel free to play around!
6. From the pulldown menu that lists all the sections in the simulation, select “Section 6: Graded Questions”. You must answer all of these questions and hit submit. Whereas the “correctness” of the practice questions in previous sections doesn’t impact your grade, these questions will, so be sure you have a strong understanding of the simulations before attempting this section. You can navigate back and forth between sections to view your previous answers if you need to review your responses.

Heredity And The Environment

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Heredity And The Environment

In Chapter 3 we learned about how heredity (our genetics) and the environment (our family and how we were raised) can contribute to our personality and who we are today.
Think about your own genetic inheritance – what traits do you share with your parents? Genetics can include such things as eye and hair color, but many personality traits are also thought to have a genetic basis.  Genes can influence such things as whether we tend to be more anxious or relaxed and easygoing.  What part do you think your genetics play in who you are today?
Next, think about the environment in which you were brought up.  What was your family environment like?  How did your parents interact with you?  What about siblings and other family members?  What do you think you learned from peers and teachers?  What part do you think your environment played in forming your personality?
Please write 1-2 paragraphs describing how genetics and environment contributed to who you are today.   word count 300 words or more

Explain and describe one physical and one chemical mutagen and its application

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Biotechnology is the use of microbes to make practical products.  The top three justifications for manipulating the genomes of cells are:
1. to eliminate undesirable phenotypic traits in humans, animals, plants and microbes.
2. to combine the beneficial traits of two or more organisms to create a new more valuable organism.
3. to create cells that synthesize products humans need.
Recombinant DNA technology employs a number to tools and techniques to isolate genes and insert them into cells grown in culture. The following are five tools of recombinant DNA technology and examples of application of the tools.
Mutagens are physical and chemical agents that produce mutation.  Some mutations are beneficial, so creating a large number of mutations increases the probability of discovering a beneficial mutation. For example the fungus Penicillium may be mutated to syntheisize a more effective antibiotic. Mutagens include uv radiation and ionizing radiation. Mueller first demonstrated the effects of X rays on Drosophilia, establishing cause and effect between radiation and genetic changes manifested in phenotypic changes.  Chemical mutagens in bacteria may be carcinogenic in humans.  The Ames test utilizes bacteria to test for mutagenic activity, and identify chemicals that may induce cell changes that lead to cancer. Ethidium bromide which may be used to visualize DNA on gel, is also a mutagen because it disrupts base pairing.
1. Explain and describe one physical and one chemical mutagen and its application.
Reverse transcriptase  synthesizes cDNA from mRNA, which is the reverse of information flow as depicted in the central dogma of molecular biology, i.e.  DNA is transcribed to RNA which is translated to peptides. Cells may have millions of copies of mRNA, so being able to synthesize the complementary DNA reveals the gene that is being expressed. In addition, cDNA contains no introns because of processing in the eukaryotic transcription, so that cDNA may be inserted into a prokaryotic cell and may be translated into the corresponding peptide.
2. Explain how reverse transcriptase differs from RNA polymerase.  Give one example of an application of reverse transcriptase in recombinant DNA technology.
Synthetic nucleic acids are synthesized in vitro using enzymes from cells. Currently there are machines that syntheized DNA or RNA by having the sequence of bases entered tthrough a keyborad.
3.  If each letter of the keyboard represents a base in DNA, how many keys does the keyboard require? How does this means of DNA synthesis differ from DNA replication in the cell?
Synthetic nucleic acids were used to elucidate the genetic code, create genes for specific proteins, synthesize probes to locate genes in a genome, to synthesize antisense nucleic acids and to make PCR primers.
4. What is the genetic code, how might a synthetic nucleotide be used to determine which amino acid corrresponds to which codon?
5. Give an example of a probe with a flourescent tag that will be used to locate a gene associated with an aggressive form of breast cancer.
Restiction enzymes cut dsDNA at restriction sites, or palindromes. Examples of restriction enzymes are EcoRI and HindIII.  There are hundreds of restriction enzymes isolated from bacteria and used to cut DNA at predictable sites.  One type of restriction enzyme cuts dsDNA to make blunt ends and the other type creates sticky ends.
6. Compare and contrast blunt and sticky ends, and give one example of each type of restriction enzyme.
Vectors insert DNA into a new cell so that the cell acquires a new phenotype.   Vectors are pieces of DNA that are small enough to manipulate in a lab, survive inside the new cell, contain a recognizalbe genetic marker and carry the gene regions necessary to ensure the gene is transcribed and translated.   Examples of vectors are plasmids, viruses and transposons.
7. Explain one risk of a viral vector that inserts itself into a necessary gene and causes a mutation.
Gene library is a collection of cells or viruses, in which each member carries a portion of a given organism’s genome.  Gene libraries provide a ready
Techniques of recombinant DNA technology include the polymerase chaing reaction (PCR)  developed by Cary Mullis.  PCR has three steps that are repeated while the same sample of primers, target gene, taq polymerase and nucleotides are cycled through three different temperatures in a microfuge tube. Gel electrophoresis separated fragments of molecules by size, shape and charge.  DNA microarrays are able to monitor thousands of genes on one plate. Applications of these techniques include diagnostics or vaccine design.
8. Explain how a subunit vaccine is designed using  genes from a pathogen and a viral vector? p502-504.
One proposed way to stop the spread of arboviruses by mosquitoes is to vaccinate the mosquito.  This type of vaccine is a transmission blocking vaccine (TBV).  One typeof TBV vaccinates the human so that a blood meal from a vaccinated human would prevent the mosquito from being infected.  Another strategy is to use the gene drive known as Crispr-Cas9 which would edit the mosquito genome to confer resistance to diseases mosquitoes transmit to humans, and is very targeted.  This requires wild type mosquitoes to mate with lab mosquitoes that have been genetically modified.  Some data would indicate the lab mosquitoes are not competitve with wild type males.
9. Explain one advantage and one disadvantage of the TBV approach for controlling the spread of arboviruses.
10. Does the public have any control over the use of gene drives to alter species in the ecosystem for public health concerns?
 

Explain the importance of monitoring plateau pressures and its use in calculating static compliance

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Learning Objectives Covered:
1. Explain the importance of monitoring plateau pressures and its use in calculating static compliance
2. Explain the use of volume-controlled ventilation and pressure-controlled ventilation
3. List and describe ventilatory support treatment plans for patient’s based on their clinical diagnosis
Background
Compliance is a measurement of the distensibility of the lung or the ability of the lung to distend. It is expressed as a change in volume divided by a change in pressure using the standard units of Liters/cmH20. The normal lung + thorax compliance of an adult is around 0.1 L/cmH20. When the compliance is low, more pressure will be needed to deliver a given volume of gas to a patient. Diseases that cause low lung compliance are classified as restrictive diseases and include Adult Respiratory Distress Syndrome (ARDS), pulmonary edema, pneumonectomy, pleural effusion, pulmonary fibrosis, and pneumonia among others. Emphysema is a typical cause of increased lung compliance.
When measuring lung compliance one must know the delivered tidal volume and must also know the change in alveolar pressure that results from the addition of that known tidal volume. Alveolar pressure is the pressure in the distensible parts of the respiratory tract and is determined by the tidal volume and the lung/chest compliance. Airway pressure is the pressure measured at the patient’s airway during mechanical ventilation. Airway pressure is equal to alveolar pressure when there is no occurrence of airflow. At the end of a mechanical inspiration, flow to the distal parts of the lungs continues even after inspiratory flow from the ventilator stops, as time is required for gas to reach the periphery of the lung. To measure alveolar pressure, one must measure the airway pressure at a time when both pressures are equal, i.e. when there is no flow.
We normally assume that alveolar and airway pressure starts out at atmospheric (our zero reference) before an inspiration starts. To equalize airway and alveolar pressures, we only have to prevent exhalation after inspiration has ceased by utilizing an inspiratory hold maneuver. The actual calculation is to divide the delivered tidal volume by the plateau pressure where the plateau pressure is the steady-state pressure measured during an inspiratory hold maneuver. Since approximate values are adequate for clinical use, clinicians use the plateau pressure minus the end expiratory pressure that is then divided into the exhaled tidal volume as measured by the ventilator. This compliance measurement is referred to as static compliance since it is measured after an inspiratory hold and there is no gas flow during its measurement.
Cstatic =                    exhaled VT (ml)                                    Pplat (cmH2O) – PEEP (cmH2O)
Where:
VT – Tidal Volume
Pplat = Plateau Pressure
A spontaneously breathing person has a normal compliance of approximately 100mL/cmH2O. In intubated patients, normal compliance is approximately 50mL/cmH2O.
Volume Control Ventilation is a type of ventilation in which a clinician sets a constant preset volume that is delivered to the patient’s lungs. In order for volume to remain constant with each breath, if compliance or airway resistance is changed then the ventilator changes the amount of pressure needed to deliver the breath. In other words, pressure will adjust to ensure that the preset tidal volume is delivered. For example, a patient receiving mechanical ventilation has developed congestive heart failure. Congestive heart failure is a restrictive disorder that results in pulmonary edema filling the interstitial spaces of the lungs. The edema makes inflating the lungs difficult. Since the ventilator is set to deliver a specific tidal volume, the pressure needed to deliver the tidal volume will be increased because the pressure needed to overcome elastic compliance is increased. Using excessive pressures to deliver ventilatory support increases the risk of injury to the lungs. This type of injury an is referred to as barotrauma. Barotrauma is injury to the lungs as a result of pressure changes. A specific type of injury that commonly occurs during delivery of mechanical ventilation is a pneumothorax, which is a rupture of one or both lungs.
The pressure used to overcome both elastic compliance (of the lungs and chest wall) and airflow resistance of the airways is referred to as the Peak Inspiratory Pressure (PIP or Ppeak). Peak inspiratory pressure is the maximum pressure in the circuit reached during delivery of a mandatory breath from a ventilator. Therefore, if volume remains constant then pressure must be adjusted to ensure that the set tidal volume is delivered despite any changes that occur in the lungs. The advantage of volume control ventilation is that alveolar ventilation remains constant so PaCO2 is not affected. During volume control ventilation, a minimum minute ventilation can be guaranteed which is useful when stabilizing ventilation.
Pressure Control Ventilation is a type of ventilation in which the ventilator delivers an inspiration until a preset pressure is reached. During pressure control ventilation, pressure is limited and if the compliance or airway resistance is changed then the volume of air delivered is changed. In other words, the preset pressure will not be exceeded but the tidal volume will change depending on changes that occur in the lungs. Take for example a patient who has developed secretions in the airway. Secretions accumulate in the airways and cause airflow resistance. The more airflow resistance that is encountered on inspiration the more pressure that is needed to overcome the obstruction. Think of pressure as a driving force. Inspiratory pressure overcomes the resistance and compliance of the lungs to inflate the lungs so the lungs can be filled with air. However, in pressure control ventilation the delivered pressure is limited. Once the set pressure is reached inspiration is terminated. This may result in the lungs may not being fully inflated which means less air delivered to the lungs with smaller tidal volumes. The more airway resistance affecting the lungs the less volume of air will be delivered. The same works for compliance. The lower the compliance (stiffer lungs) the less volume of air will be delivered.
Prompt
For this assignment, you will provide detailed responses to the following questions.
Be sure to review the link below regarding Calculations Commonly Performed in Respiratory Care
RT Equations
1. Describe the difference between dynamic compliance and static compliance. What useful information do we receive by monitoring dynamic compliance? What useful information do we receive by monitoring static compliance?
2. Calculate compliance given Vt = 500 ml, Peak airway pressure = 30 cmH2O, Plateau pressure= 25 cmH20, PEEP = 10 cmH2O.
3. Calculate static and dynamic compliance given Vt = 760 ml, Peak airway pressure = 38 cmH2O, Plateau pressure= 33 cmH20, PEEP = 7 cmH20.
4. Calculate static and dynamic compliance on a patient who is on a volume ventilator and has the following measurements: Tidal Volume = 780 ml, Peak Airway Pressure = 45 cmH20, Plateau pressure 40 cmH2O,  PEEP = 10 cmH2O.
5. Calculate static and dynamic compliance: Tidal Volume 800 ml, Peak Airway Pressure 20 cmH2O, Peak Inspiratory Pressure 30 cmH2O, Plateau pressure 35 cmH2O, Peep 10 cmH2O.
6. Explain permissive hypercapnia and why this strategy is used for ventilating COPD patients in acute respiratory failure.
7. What is the recommended strategy for ventilating patients with ARDS?
8. What is the recommended strategy for ventilating patients with traumatic brain injury?
Submit your answers in at least 500 words on a Word document. You must cite at least three references to defend and support your position.