Why is it important to be aware of the differences between prokaryotic cells and eukaryotic cells when using prokaryotic models to study eukaryotic cellular processes or molecules?  

You have discovered a new single-celled organism. Describe how you would classify it as Bacteria, Archaea, or Eukarya based on the genetics strand of cell biology. Your answer should be a couple sentences long and should include at least one tool or method you would use, the information that tool or method would provide, and what information you would expect to obtain if your organism belonged to each of the above domains.

DNA is continually damaged by exposure to chemical agents and ionising radiation. What are the effects of these agents on the DNA molecule? Choose one specific example and show how the damage caused might be repaired.

Describe the process of gene regulation using the diphtheria toxin gene. More correct, relevant detail is better.

Question 3.

Human haemoglobin is a complex protein molecule made up of four poly-peptides joined to an iron-containing haem group. In normal human adult haemoglobin, haemoglobin A, or HbA, two kinds of polypeptides designated as alpha and beta are found. Two identical alpha and two identical beta chains plus the haem group make up each molecule of haemoglobin A. Haemoglobin S, or HbS, is a haemoglobin variant occurring in individuals affected with the heritable disorder sickle cell anaemia. A comparison of the amino acid sequences of the polypeptides in haemoglobins A and S indicates that the alpha chains in the two molecules are identical, but that the beta chains differ in a single interior amino acid.

a.   How many of genes are necessary for the synthesis of haemoglobin S in an adult who is homozygous for the S allele?

b.   Assuming that the gene for the beta chain of HbS arose from the gene for the beta chain of HbA through a single mutation, what general type of mutation was most likely responsible?

c.   The difference between the beta chains of haemoglobin S and A is restricted to the sixth amino acid from the amino (-NH₂) end of the polypeptide. In haemoglobin S, the amino acid at the site is valine and in haemoglobin A it is glutamic acid. From your knowledge of the genetic code (and with reference to the genetic code) what can you deduce about the specific (and simplest) base alteration in the beta polypeptide that would produce the amino acid substitution?

1. Explain the role of FSH and LH in the reproductive systems of humans. What does each hormone do, and what parts of the reproductive tract are affected?

2. Why is the action potential considered an "all or nothing" event?

3. Describe two ways in which the nervous and endocrine systems interact to help regulate body systems.

Please answer these 3 questions and please write shortly Thank you.

are polysaccharides formed by hydration or dehydration reactions?

What is the classification and history of Providencia?

What is the significance of it? How does it relate to science, environment, or health?

Is it pathogenic? If so, what does it cause and what is the treatment? Who does it affect? What part of the world is it found in?

Is there anything about Providencia that makes it unique and interesting?

Why are antibiotics ineffective against viral infections?

1. Amino acid symbols and properties. Complete the table. Spend several minutes looking at Table 3-1 first. Then try to fill in the below by memory. Then try to remember those you forgot. The one and two letter codes are how parts of genome sequence are reported. You will need to understand this language to interpret these data, which are increasingly used in medicine and research. These symbols are used in many subsequent lecture as well.

For this discussion assignment, select a fungal, helminth, or parasitic species of your choice and prepare an initial post describing the optimal growth conditions, location, and unique characteristics which helps the microbe adapt to this niche. Include images if possible.

Is there any therapeutic application for this microbe in healthcare?

Please no picture or written responses - only typed answers

PARASITOLOGY QUESTION:

Amoeba case study

Calatagan is a third-class municipality in the province of Batangas, Philippines. It has a total population of 30,500 with a total of 8 barangays. The municipality’s major revenue comes from agriculture and aquaculture. A section of the population is employed in “Ang Pulo,” an island housing a mangrove forest conservation park located in the northeast. Some residents of Calatagan are settled along the major highway that connects it to neighboring municipalities, while some live further inland, usually near farms. Major streets are cemented but small streets are not. Deep well is the main source of water but there is one water distillery station serving three barangays in the municipality. In the summer of 2005, there were 950 cases of a rare eye infection in one barangay that affected residents of different ages. The infection is characterized by severe pain and reddening of the cornea. Antiviral drugs where administered but the patients’ condition did not improve. There were also 1500 reported cases of diarrhea by the RHU. Stool examination results from specimens submitted by patients revealed an increase in WBC count. Strange crystal-like structures were also seen under the microscope in some of the stool specimens. The mayor of Calatagan ordered an immediate investigation of the probable cause of the cases.

Questions to answer:

1. Identify the probable cause of the incidents in Calatagan, Batangas. Justify. (provide references for your answers)

2. What could have been the sources of infection of the residents in Calatagan? Describe the probable mode of infection for each identified cause. Cite examples and references.

3. Briefly provide a possible plan of action on how to control the cases in Calatagan.