Dissection of a Sheep's Kidney and Function & Simulation of Urine Analysis Ib Biology Lab Report

Dissection of a sheep's kidney and function and simulation of urine analysis.

International College

12/05/2007

1. Dissection of a sheep's kidney

Material

• One sheep's Kidney per student
• Scalpel
• Dissecting Tray
• Disposable Gloves

Procedure:

• Cut the kidney longitudinally along a plane passing in the hilum (region where the ducts leave the kidney) and the convex side. Observe in each part obtained: Cortical region, medulla region, pelvis, renal artery, renal vein and ureter.
• Draw and label all the parts observed

Data Collection:

2. Simulation of urine analysis

Material required

12 test tubes Urine sample without glucose
Glass-marking pencil Urine sample with phosphate
Test tube rack Urine sample without phosphate

Test tube holder Urine sample with albumin

10-ml graduated cylinder Urine sample without albumin
Hot plate Urine sample with chloride
Bunsen burner Urine sample without chloride
400-ml beaker Benedict's solution
Matches Silver nitrate solution
Urine sample with glucose 10% acetic acid solution

Procedure

• Part A: Test for glucose

1. Place two test tubes in a rack, label one G and keep the other unlabeled
2. Prepare a hot water bath using a 400-ml beaker
3. Add 3ml of a benedict reagent to both test tubes
4. Add 3ml of urine sample with glucose to the test tube labeled G, and 3 ml of urine sample without glucose to the unlabeled test tube
5. Record the appearance of the substances in both tubes, then place them in the hot water bath for 2 minutes.
6. After 2 min, remove the test tubes from the hot water bath, place them in the rack and record any change in appearance in both.

• Part B: Test for Chloride

1. Place two test tubes in a rack, label one with a C and keep the other unlabeled
2. Add 5 ml of the urine sample with chloride to the test tube labeled C and 5 ml to the urine sample without chloride to the unlabeled test tube.
3. Record the appearance of the substances in both tubes.
4. Carefully add 3 drops of silver nitrate solution to each test tube
5. Record the appearance of the substances after the addition of silver nitrate solution.

• Part C: Test for Albumin

1. Place two test tubes in a rack, label one A and keep the other unlabeled
2. Half fill the test tube labeled A with the urine sample with albumin and the unlabeled one with the urine sample without albumin
3. Record the appearance of each substance in the tube
4. Using a test tube holder pass the top surface of each tube over the flame of a Bunsen Burner for 15 - 20 sec then record the appearance of each substance
5. Add 5 drops of acetic acid to each test tube and record your observations

• Part D: Test For Phosphate

1. Place two test tubes in a rack, label one P and keep the other unlabeled
2. Half fill the test tube labeled P, with the urine sample with Phosphate and the unlabeled one with the urine sample without Phosphate
3. Record the appearance of substances in each test tube
4. Using a test tube holder pass the top surface of each test tube over the flame of a Bunsen burner for 15 - 20 seconds. Record the appearance of the substances in the two tubes after heating
5. Add 5 drops of acetic acid to each test tube. Record your observations

• Part E: Testing an unknown urine sample

1. Obtain a sample of artificial urine marked unknown. Record the identification number of the sample
2. Using four clean test tubes perform the glucose, chloride, albumin, and phosphate tests on your unknown sample. Follow the above procedures.
3. Record your results, and identify your sample

Data Collection

Part A: Test for glucose

Table 1: Notable changes in test tubes before and after administering test revealing presence of glucose

Tubes

Initial Observation (before heating with Benedicts solution)

Final Observation after 2 minutes (after heating in water bath)

Tube labeled G

(Urine sample + Glucose)

Transparent blue color + light yellow/green transparent color at the top

Dark red-brick murky color

Unlabelled tube

(Urine sample without Glucose)

Transparent blue color + light yellow/green transparent color at the top

No change

Part B: Test for chloride

Table 2: Notable changes in test tubes before and after administering test revealing presence of chloride ions

Tubes

Initial Observation

Final Observation (after adding 3 drops of silver nitrate)

Tube labeled C

(Urine sample + Chloride )

Faint Yellow Color

Dark opaque yellow + more condensed than initial + forming a precipitate.

Unlabelled tube

(Urine sample without Chloride)

Faint Yellow Color

No Change: Still faint yellow

Part C: Test for albumin

Table 3: Notable changes in test tubes before and after administering test revealing presence of albumin

Tubes

Initial Observation of solutions

Observation after heating with Bunsen burner for 15-20sec

Observation after adding 5 drops of acetic acid solution

Tube labeled A

(Urine sample + Albumin )

Clear Yellow color + White precipitate

-Yellow transparent color + formation of gas bubbles and cloudy white particles. -Formation of a white albumin precipitate.

Heavy formation of solidified albumin at top

Unlabelled tube

(Urine sample without Glucose)

Clear Yellow Color

Yellow transparent color, little formation of gas bubbles (insignificant).

No change

Part D: Test for phosphate

Table 4: Notable changes in test tubes before and after administering test revealing presence of phosphate

Tubes

Initial Observation of solutions

Observation after heating with Bunsen burner for 15-20sec

Observation after adding 5 drops of acetic acid solution

Tube labeled P

(Urine sample + Phosphate )

Clear Yellow color

Stronger yellow color with significant formation of gas bubbles and sudden eruptions

Foggy Opaque Yellow Color

Unlabelled tube

(urine without phosphate)

Clear Yellow color

Formation of little gas bubbles

No change

Part E: Testing an unknown urine sample

Unknown substance to test: unknown substance C

Tubes and tests administered

Indicator

Initial Observation

Final

Observation (after adding indicator)

Tube G (testing for presence of glucose)

Benedicts solution + heat

Clear yellow color + white precipitate

Dark red-brick murky color

Tube C (testing for presence of chloride)

Silver nitrate + heat

Clear yellow color + white precipitate

Dark condensed yellow + Forms a precipitate.

Tube A (testing for presence of albumin)

Acetic acid + heat

Clear yellow color + white precipitate

-Yellow transparent color + formation of gas bubbles and cloudy white particles. -Formation of a white albumin precipitate.

Tube P (testing for presence of phosphate)

Acetic acid + heat

Clear yellow color + white precipitate

Foggy Opaque Yellow Color

Conclusion and evaluation

Simulating urine analysis

The experiments and testing were conducted on artificial urine. Two test-tubes were allocated for each experiment, one as a control and the other a variable. Thought all the experiments the control test tube was filled with urine clean of the presence of any supplementary substances. The variable tube in each experiment (A through D) consisted of urine containing 1 of 4 substances, the latter being Glucose, Chloride, Albumin and Phosphate.

In each experiment, we added a reagent to identify the presence of the variable substances:

In Part A we added Benedict's reagent, which forms a red-brick precipitate in the presence of Glucose, due to the oxidizing power it has reducing sugars (glucose being one of them).

In Part B, the Chloride test, we added silver nitrate (AgNO3), which reacts with Cl2 to form AgCl, producing a white precipitate.

In Part C, the albumin test, we first heated the solution and then added acetic acid, which is used to detect the presence of albumin, which forms a heavy solidified white precipitate.

In Part D, the Phosphate test, we again heated acetic acid, but this time to detect the presence of phosphate, which forms a foggy yellow color.

In Part E, we were handed a urine sample with an unknown substrate content. We conducted all 4 experiments again using only this sample, to test for any forming precipitates or changes in color, so that we could identify the variable. We separated the contents of the tube into 4 other tubes in order to conduct one of the four tests on each one. After finishing the experiments, we tabulated our observations and compared them to our results from parts A through D. Results were similar to those observed previously in the test tubes containing chloride, glucose and phosphate. These results allow us to assume that glucose, chloride, albumin and phosphate were present in our unknown.

Since the urine experiment only had qualitative data to be reported there was not a large margin for false data to be reported in the whole experiment.

Dissection of a sheep's kidney and function

The dissection of the sheep's kidney was very insightful compared to just observing the drawn diagrams in our textbooks. However, the kidneys sizes were too small and did not have its different components (such as veins, arteries and valves) died in different colors in order for the student to easily identify them.