lab report -experiment -hemophilia
General Style and Format (10 marks)
Follow the style used by articles from the SAMPLE ISSUE in the journal Ecology (http://www.esajournals.org/loi/ecol). Base your formatting on the PDF version of the journal article, not the “Full Text” version (figures and tables should appear close to the text that refers to them, not at the end of the document).
Use single line spacing, typical 1” margins and Times New Roman 12 point font.
See also the “BIOL 102, 103 Scientific Reports – Helpful Hints” document.
Title Page or Title Section
1. title
• should be descriptive but specific (should not exceed 14 words)
• include the main objective of the study
2. student name and number
3. TA name
4. course name
5. date submitted
Abstract (it’s easiest to write this section last) (= ½ page; 5 marks)
A brief description of your report which briefly summarizes:
1 the purpose of the study
2 the main details of the methods (assume your study involved human subjects, not a simulation)
3 the most important result(s)
4 the main interpretation(s)/conclusion(s) of your study
Introduction (= ¾ page; 10 marks)
States your motivation in conducting the study and provides the reader with context. You already provided most of the information you need to include in your introduction in Part 1 (Questions 1,2 and 3) of this assignment. Include some additional information about your selected genetic disorder, with appropriate references.
Organize into 3 sections:
1. why was this study conducted?
• what is/are the broad question(s) being asked? why is there an interest in this topic?
2. what is currently known about this topic?
? usually the longest portion of the introduction
? provide a concise review of relevant and current research
3. how does this report contribute to the body of knowledge on this topic?
? state your purpose
Introduction:
Hemophilia is a mostly inherited genetic disorder that impairs the body’s ability to make blood clots, a process needed to stop bleeding. Even though the disorder is very rare, but it is incurable and there are still 20,000 people in USA suffer with this disorder. Hemophilia patients have lower clotting factor level of blood plasma or impaired activity of the coagulation factors needed for a normal clotting process. Thus when a blood vessel is injured, a temporary scab does form, but the missing coagulation factors prevent fibrin formation, which is necessary to maintain the blood clot. A hemophiliac does not bleed more intensely than a person without it, but can bleed for a much longer time. In severe hemophiliacs even a minor injury can result in blood loss lasting days or weeks, or even never healing completely. In areas such as the brain or inside joints, this can be fatal or permanently debilitating.Like most recessive sex-linked, X chromosome disorders, hemophilia is more likely to occur in males than females. This is because females have two X chromosomes while males have only one, so the defective gene is guaranteed to manifest in any male who carries it. Because females have two X chromosomes and hemophilia is rare, the chance of a female having two defective copies of the gene is very remote, so females are almost exclusively asymptomatic carriers of the disorder. Female carriers can inherit the defective gene from either their mother or father, or it may be a new mutation. Although it is not impossible for a female to have hemophilia, it is unusual: a female with hemophilia A or B would have to be the daughter of both a male hemophiliac and a female carrier.Hemophilia is usually inherited, meaning that it is passed on through a parent’s genes, so the purpose of this experimental is to study how hemophilia is inherited
Methods (= ½ page; 5 marks)
Provides all the methodological details for a competent biologist (working in the same field) to reproduce the experiment(s).
? briefly describe what was done and how (assume your study involved human subjects like in a clinical setting where medical interviews are conducted, not a simulation)
? justify the experimental design and sampling details (you already spent some time considering sample size for Question 5 in the first part of this assignment)
? write in the past tense, in complete but concise sentences and paragraphs
Lab Procedure
• Choose Human from the Species Selector and one of the following four genetic disorders from the Traits menu: colour blindness, dwarfism, hemophilia, or sickle cell anemia. Make sure Mendelian is checked for Experimental Setup.
• Set your first combination of parental alleles. For practical purposes, you may assume that every couple in your study had 4 children: set the number of offspring to 4.
• Click the cross button repeatedly until the parents have produced ~100 F1 offspring – a large enough sample size to determine the pattern of inheritance of the trait. Make sure that the Include Male/Female box in the lower left corner of the results box is checked.
• Save or record your data. Click the Reset button at the bottom.
• Repeat steps 2-4 with all possible combinations of parental alleles.
MALE AND FEMALE ARE COUPLES
N= NORMAL
A=AFFECT
FEMALE NA=CARRIER
MALE NA= AFFECTED
125 COUPLES EACH OF THEM HAVE 4 CHILDREN
Results (= ½ page, not including figures; 10 marks)
Presents the findings of your experiment in figures and/or tables as well as text. Include the graph you submitted for Question 6 in the first part of this assignment and any other results you consider relevant.
• present data in a straightforward manner without engaging in interpretation/ discussion
• summarize the most important data and findings presented in the figures and tables (especially patterns or trends)
• without being redundant regarding specific details, enough information should be provided in the text such that the reader would be able to understand the results of each experiment without looking at the figures and tables
• figures and tables should be placed on the same or next page after they are referred to (e.g. “Figure 1”) in the text
Figures and Tables
• data are only presented once (i.e. a figure or a table but not both)
• figure captions begin with a descriptive statement and are located beneath the figure; table captions (or headings) are located above the table (refer to examples in the sample issue of the journal Ecology)
• captions should be informative enough that the figure/table can be understood without reference to the main text
• graphs must have properly labeled axes (with correct units) and, if useful, an appropriate legend to identify different data symbols
Discussion (= 1½ pages; 15 marks)
Provides analyses and interpretations of results obtained in the study, relating back to the purpose posed in the introduction and to the relevant current literature.
May be organized into 3 sections:
1. introduction to the discussion
• briefly revisit points first brought up in the introduction to tie everything together
2. analysis and interpretation of results
• the longest portion of the discussion
a) introduce a result, or some aspect of a result with respect to the purpose; do not just reiterate the results as were presented in the Results section, rather you should focus on a key aspect that you wish to interpret
b) provide an interpretation of the result based on your data combined with background scientific knowledge
c) does your result/interpretation agree with the literature? if not, provide a possible explanation (assume you were working with human subjects; provide explanations only in terms of biological possibilities)
3. summary
? summarize any conclusions you have drawn from your study and discuss potential implications with regard to the broader question(s)
? include suggestions for future work
Points to remember when writing this section:
• writing should be concise, the paragraphs should flow logically from one to the next, and your argument should be easy to follow
• the bulk of the discussion should be the analysis of (but not a repeat of) your results, not a review of what is already present in the literature; citations are meant to play a supporting role only and should be included only if they are relevant to your arguments
• all of the main results should be discussed, even (especially) if they were unexpected and appear not to agree with your other results or with what is presented in the literature
• some instructors will ask that problems encountered during your experiment(s) be discussed, especially if they hamper firm conclusions
Literature Cited (= 6 primary references; 10 marks)
A listing of all the references you have cited.
Points to remember when writing this section:
? use the referencing style in the journal Ecology and pay attention to details such as order of authors (alphabetical, by last name of first author), capitalization, punctuation, abbreviation, indentation and text emphasis (e.g. no bold or italics); include journal volume number but not issue number
? also refer to Ecology for examples as to how citations should be inserted within the body of your report
? be sure to include all (and only) the works cited in your text
Points to consider when selecting references:
• include enough references to substantiate (or contradict, as the case may be) your arguments but not so many that your text looks like a “cut and paste” of citations
• attempt to include the most recent and relevant works
• in most cases references should be exclusively primary literature; reviews (secondary references) should only be cited to indicate that work has been done in a certain area, to make note of commonly held ideas or theories, or as a means to provide the interested reader with a source of additional information
• do not include textbook, encyclopedia, general web site references or anything that is general knowledge; only in certain circumstances should you include anything other than peer-reviewed publications
• do not quote extensively from any other work; summarize findings from other studies in your own words
Overall Impression (15 marks)
See “Overall Impression Marks for Research Reports” on page 5 of the “BIOL 102, 103 Scientific Reports – Helpful Hints” document.
