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Writing Formal Lab Reports

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All labs must be written or typed and be submitted to the teacher in a pocketed lab notebook (2”, 3-ring binder with pockets). Always use third person (no personal pronouns) when writing all parts of a lab report. A cover sheet with the lab title, your name, date, and period should be stapled to the front of the lab report. Place the lab report in the front pocket of the Notebook. When typing your report put lab headings and lab questions in bold type (underline when writing). Use Times New Roman font 12 point only and only 1″ margins. Include a floppy disk or CD with your lab report in your lab folder.

Your lab report should be written using the following format:  (Be sure to left align & bold headings)

Title
The title should indicate clearly & concisely the subject and scope of the report. 

Introduction
The introduction should give background information about the experiment. It should also state the purpose of the investigation.

Hypothesis
The hypothesis should be a single statement telling the exact thing you are trying to prove in your experiment.  Never write this statement using “first person”.

Materials
This section includes a list, written in paragraph form, of all the materials and equipment used.  Be sure to include specific amounts and concentrations of chemicals used. 

Methods
This section includes one or more paragraphs explaining the step-by-step procedures used.  The description should be so thorough that someone else could use your listed materials and procedures to conduct the same experiment & get the same results. 

Results
All data should be collected and organized in a logical order.  Results should be illustrated as charts, tables, graphs, &/or diagrams. All graphs should include a title, the independent variable on the horizontal axis, and the dependent variable on the vertical axis.  All lab questions and answers should be included also with this section. ( Bold the questions & italicize the answers)

Error Analysis
Include any important factors that you think may have actually affected your results.

Discussion and Conclusion
In this section, you should interpret the collected data and relate it to the restated hypothesis.  Explain the significance of the results. If additional research and experimentation is needed, explain in this section. 

 

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Lab 8   Population Genetics Write Up

Introduction:

Read and summarize the lab introduction being sure to include both HW equations and what each variable stands for, explain what a population is and what type of population HW applies to, list and explain the 5 assumptions necessary for HW to be true, and be sure to give a brief description (not the procedures) for each of the 4 cases in the lab.

Hypothesis:

Use the objective (s) for the lab and write them into a single statement for your hypothesis.

Materials:

In sentence form list the materials you will need including paper, pencil, PTC paper, index cards, and calculator.

Procedure:

Type 4 paragraphs, one for each case study. Remember to write in paragraph form without numbering steps.

Data & Analysis:

·        Include the 4 case study sheets with all calculations completed

·        Write out and answer the questions from your lab sheet. Remember to underline the question, but not the answer.

·        Write out and answer the questions at the end of Lab 8 in your lab manual.  Remember to underline the question, but not the answer.

Conclusion:

·        Explain the effect each of the situations had on the allele frequencies and genotypic frequencies (include supporting data)

·        Explain why each condition could or could not actually occur in nature

·        Explain the effect natural selection has on recessive traits

·        Explain how the HW law helps determine whether evolution is occurring

Click Here For Case Study Sheets

 

 

 

Lab 10   Physiology of the Circulatory System

 

Introduction: The human circulatory system is a collection of structures thorough which oxygen and nutrient rich blood flows to all tissues of the body for metabolism and growth, and to remove metabolic wastes. The blood is pumped to these tissues by the heart through a circuit composed of arteries, arterioles, capillaries, venules, and veins. Oxygenated blood is pumped to the tissues from the left side of the heart, whereas deoxygenated blood is pumped to the lungs from the right side of the heart. This circuit where gas exchange takes place within the alveoli of the lung is very important and is known as the pulmonary circuit. When the body is exercised changes can take place in the circulatory system that allow more blood to pass to actively respiring muscle cells and less to nonmuscular tissue. Increased heart rate, arterial pressure, body temperature, and breathing rate also occur during exercise.

Arterial blood pressure is directly dependant on the amount of blood pumped by the heart per minute and the resistance to blood flow through the arterioles. This is an important measurable aspect of the circulatory system and it is measured using a sphygmomanometer. This device has an inflatable cuff that connects to a hand pump and a pressure gauge, graduated in millimeters of mercury, by rubber tubing. The cuff is wrapped around the upper arm and inflated, the person taking the pressure then listens for two sounds and observes the gauge to determine what the blood pressure is. The systolic number is determined by the first noise heard as the cuff is deflated, and the diastolic number is determined by the last distinct noise heard.

Hypothesis: From this experiment it is expected that a subject’s heart rate and blood pressure will change during rest and exercise based on how physically fit they are. If the subject is in good shape the heart rate will not increase significantly and the blood pressure will increase. The opposite is true of someone in poor shape.

Materials: The materials used in this experiment include a blood pressure kit, alcohol swabs, a stopwatch, two depression slides, a cotton ball, four rubber bands, a pipet, a petri dish, a Daphnia culture, a stereomicroscope, and some ice.

Methods:

A. Measuring Blood Pressure: To measure blood pressure, one member of the lab group sat down in a chair, rolled up his sleeve, and then the sphygmomanometer cuff was placed around his upper left arm at heart level. The cuff was then pumped to 200mm Hg, which is safely higher than the blood pressure of the subject. The stethoscope was then placed in the well of the subject’s elbow, where the brachial artery is located, and pressure was slowly released as the taker listened for a pulse. The pressure on the gauge was noted when first sound of Korotkoff was heard, which is the pressure that blood is first able to pass through the artery during systole, representing systolic pressure. The sounds of Korotkoff are heard between the systolic and diastolic blood pressures. The diastolic pressure is the reading of the gauge at the time the sounds of Korotkoff can no longer be heard. The subject’s blood pressure was taken two more times and an average was calculated and recorded in Table 1.

 

Average Blood Pressure

 

 

	Systolic Pressure		Diastolic Pressure
Age in Years	Men	Women	Men	Women
10	103	103	69	70
11	104	104	70	71
12	106	106	71	72
13	108	108	72	73
14	110	110	73	74
15	112	112	75	76
16	118	116	73	72
17	121	116	74	72
18	120	116	74	72
19	122	115	75	71
20-24	123	116	76	72
25-29	125	117	78	74
30-34	126	120	79	75
35-39	127	124	80	78
40-44	129	127	81	80
45-49	130	131	82	82
50-54	135	137	83	84
55-59	138	139	84	84
60-64	142	144	85	85
65-69	143	154	83	85
70-74	145	159	82	85

 

B. Physical Fitness Test: The first numbers recorded from this section of the experiment were those of standing vs. resting blood pressure. To do this a member of the lab group had to lie down on a table for five minutes. After five minutes the subject’s blood pressure was taken while he was still lying down and the numbers were recorded in Table 2. The subject remained lying down for another two minutes, stood up, and their blood pressure was taken again. The standing systolic pressure was subtracted from the resting systolic pressure and recorded in Table 2. A chart was used to determine the number of points received by the subject and recorded in Table 3.

The next part of this section is where the subject’s standing heart rate was determined. Taken by the subject was the radial artery pulse by counting the number of beats for 30 seconds. That number was multiplied by 2 to obtain the number of beats per minute. That number was recorded in Table 3. Another chart was used to determine the amount of points the subject received for this section and that number was also recorded in Table 3.

Next the resting heart rate was determined by having the subject lie down on a table for five minutes. After five minutes the subject’s pulse was taken and recorded in Table 3. Once again a chart was used to determine the number of points the subject received for this section of the experiment and the number was recorded in Table 3.

Next the Baroreceptor reflex test was given to the subject. The subject had to lie down for five minutes, stand up quickly, and record the pulse. From this number the resting heart rate was subtracted and recorded in Table 3. A chart was then used to determine the number of points the subject received for this section and recorded in Table 3.

The endurance test was the last leg of this section of the experiment. To do this the subject stepped up with one foot onto an 18 inch high surface and then brought up the other foot onto the surface. This was continued for 15 seconds, and then his pulse was taken at several intervals. First the pulse was taken right after the exercise for 15 seconds and multiplied by four. This was repeated one more time after that as well. Then the pulse was taken every 30 seconds for 120 seconds after that. The data was recorded in Table 4. The amount of time it took for the subject’s heart rate to return to normal was figured and a chart was used to award points. These heart rates were then compared to the standing heart rate. Next, the standing heart rate was subtracted from the rate taken right after exercise, and yet another chart was used to award points.

 

C. Investigating Heart Rate in Daphnia: Two depression slides were obtained and a small piece of cotton was placed in the center of one of the slides. Several Daphnia were placed on the slide with a pipet and the other slide was placed on top of this slide and wrapped together with a rubber band on each end. A petri dish was filled with room-temperature water, 1cm deep and the slides were placed into it. The heart of the largest Daphnia was then located under the stereomicroscope and the number of beats in 15 seconds was determined, multiplied by four, and the results placed in Table 5. Into the dish was then added ice water and the same Daphnia’s heart rate was determined and recorded in Table 5. Gradually warm water was added and the heart rate was taken at five minute intervals until the normal heart rate is noted. These results were put in Table 5.

Results:

Table 1

 

 

Blood Pressure	Systolic	Diastolic
Trial 1	115	72
Trial 2	115	70
Trial 3	115	74
Average	115	72

 

Table 2

Standing vs. Resting Blood Pressure

 

Position	Systolic	Diastolic
Lying Down 5 min.	110	72
Lying to Standing	120	72
Change	10	0

 

 

Table 3

Fitness Points

 

Activity	Result	Fitness Points
Change in Blood Pressure	10	3
Standing Pulse Rate	78	3
Resting Pulse Rate	64	3
Baroreceptor Reflex	76	3
Heart Rate Recovery After Exercise	28	4
Heart Rate Increase After Exercise	18	2
Total Points	–	18

 

 

Table 4

Heart Rate After Exercise

 

Interval	No. of Beats		Heart Rate
0 to 15 sec.	24	X4=	96
16 to 30 sec.	19	X4=	76
31 to 60 sec.	35	X2=	70
61 to 90 sec.	35	X2=	70
91 to 120 sec.	35	X2=	70

 

 

 

Total Score	Cardiovascular Fitness
17 to 18	Excellent
14 to 16	Good
8 to 13	Fair
7 or less	Poor

 

 

 

Questions:

1. What changes occur in the circulatory system when a person stands up from a prone position? How do these changes affect the heart rate and blood pressure of the individual?

 

The circulatory system is not working very hard when a person is at rest so when that person stands up suddenly the blood pressure and heart rate of that person increase.

 

2. How does the circulatory system, and the heart in particular, of a conditioned athlete differ from that of a person in poor shape?

 

The heart of a conditioned athlete is stronger because it has been worked harder pumping more blood when that person exercises. The heart of a person in poor shape has not been worked as hard.

 

3. Why is high blood pressure dangerous? What health problems does it lead to?

 

High blood pressure is dangerous because the heart has to work to hard to push the blood through the various veins and arteries and a heart attack can occur.

 

4. What sort of behaviors encourage high blood pressure? Why?

 

Eating fatty foods and not exercising cause high blood pressure because the heart is not working hard to pump the blood, which makes it weak.

 

Table 5

 

 

Temperature (C)	Heartbeats per Minute
Room Temperature	200
0 to 5	84
10	160
15	152
20	204
25	200
30	212
35	216

 

 

Change in Metabolic Rate

 

 

Temperature Range	Rate of the reaction (change in heart rate)
0-10	Q10 =1.9
10-20	Q10 =1.275
20-30	Q10 =1.04

 

 

 

Questions:

1. Why does the rate of activity of ectothermic organisms increase with a rise in the temperature of its environment? How is this different from an endothermic organism?

 

Ectothermic organisms’ body heat is determined by the environment, so their metabolic rates also change with this. Endotherms have a constant body temperature and do not change their metabolic rate strictly based on environmental conditions.

 

2. If this experiment were performed on a human subject, what results would you expect? Explain.

 

A human’s heart would also be affected by the temperature changes, but not to the extent that the Daphnia heart did.

Error Analysis: The only possible source of error in this lab would have been the slight misreading of the gauge on the sphygmomanometer.

Conclusions: Cardiovascular fitness is very important to living a healthy life. If one doesn’t exercise and eat healthy foods they run a risk of being in poor shape and having a heart attack or other serious things. Heart rate and blood pressure readings can give a person a good idea about how healthy they are or how healthy they need to be. Blood pressure is so important to a person’s health it is checked at every visit to the doctor or hospital.

 

BACK

Introduction to Biology Review

1. All living things are called _______________________.

2. The approximately 40 million types of living things on Earth are known as ______________________.  How many have been identified? __________________.

3. The land, water, and air on Earth that sustains life is known as the ___________________________.

4. A species is a group of organisms so similar to one another that they can _______________________ or _____________________________.

5. Evolution simply means ______________________________________.

6. When hereditary information from two parts of a single organism or from two organisms of the same species is combined it is called  _______________________.

7. An organism that must take in food is a(n) _________________________.

8. The encoded, genetic instructions for making many other molecules necessary for life is called  __________________. 

9.  Produces greatly magnified images of surface details ________________  _____________  __________________  or ______________.

10. Increase of an object’s apparent size is ________________________________.

11. The production of offspring is called __________________________________.

12. The formation of two cells from an existing cell is called ______________   _____________________________.

13. Produces a greatly magnified image of internal details ___________________  _______________   ______________ or _____________.

14. Ultimately, almost all living organisms get their energy from the _______________.

15. ______________________  reproduction involves no recombination of genetic material, or exact duplication of the parent.

16. ________________________ reproduction involves combining hereditary information from two  different species or from two organisms of the same species.

17. A short segment of DNA that contains instructions for a single trait is called a(n) __________________________.

18. What is the smallest unit of life capable of carrying out all life functions?

19. Sum of all chemical processes of an organism _______________________________.

20. Through the process of ____________________________________ plants capture the energy from the sun and change it into a form of energy that can be used by living things.

21. Capability of showing clear details refers to ________________________________.

22. The study of how organisms interact with each other and their environment is called ___________________________.

23. The process by which an adult organism arises is called _______________________.

24. When hereditary information from different organisms is not combined it is called __________________________ reproduction.

25. An organism that makes its own food is called a(n) __________________. Give an example.

26. To maintain their internal organization, all living things must have a constant supply of _____________________.

27. Reproduction involves the transfer of genetic information from _____________________  to ____________________.

28. The stable internal environment maintain by living things is called ________________.

29. The most important driving force in evolution is ____________________.

30. The scientific process that involves using the five senses is _______________________.

31. Data that are quantitative are always represented by __________________________.

32. A hypothesis is a statement that can be _______________________________.

33. A broad and comprehensive statement of what is believed to be true is a(n) ______________________________.

34. A small part used to represent an entire population is called a(n) __________________________________.

35. Organisms that are composed of only one cell are called _________________.

36. Organisms composed of more than one cell, such as a plant, are called ______________________.

37. What type of microscope has the greatest magnification?

38.  Cell division and cell enlargement together results in ____________________.

39. Cell division and cell differentiation results in ________________________.

40. How does a theory differ from a hypothesis?

41. List the six major characteristics of living things.

 

42.  Compare cell division in unicellular & multicellular organisms.

 

43. Why is it important for scientist to communicate about their work?

 

44. Why do scientists use SI rather than the system of measurement adopted for use in their own country?

45. How do autotrophs differ from heterotrophs in obtaining energy?

46.  Would a field biologist who studies the ecology of a bird species necessarily use the same scientific methods as a laboratory biologist who studies how a virus infects cells?  Why or Why Not?

47.  How does the growth of a nonliving thing differ from growth of a living thing?

48. Why are so many organisms yet to be discovered, identified, and described?

 

49. List the six major themes of biology.