BIO 250 Lab 14 The Urinary System COMPLETE NEW SOLUTION 2025
Straighterline
Student Name:
Access Code (located on the lid of your lab kit):
Lab Report Format Expectations
Utilize college level grammar and professional formaṄng when completing this worksheet.
Submissions without proper formaṄng, all required photos or sufficient responses will be
rejected. Pre- lab Questions
1. What is the function of the ureter?
The ureter is a tube that carries urine from the kidney to the urinary bladder. Each
kidney has one ureter. The urine is transported through peristaltic movement of the
smooth muscle in the ureter wall.
2. Compare and contrast the male and female urethra.
The male urethra is longer than the female urethra and serves a dual purpose, it carries
both urine and semen out of the body. It also passes through the prostate gland and
penis. While on the other hand, the female urethra is shorter and only serves to carry
urine. It opnes just above the vaginal opening.
3. Describe the two layers of the kidneys.
The kidney has two main layers: the cortex and the medulla. The cortex is the outer
layer and contains the glomeruli and most of the nephrons which filters the blood. The
medulla is the inner layer and is made up of renal pyramids, which contains the
collecting ducts that channel urine toward the renal pelvis.
,Lab 14 The Urinary BIO202
L
System
EXPERIMENT 1: KIDNEY FILTRATION
Introduction Questions
1. What specific part of the kidney does the dialysis tubing represent? What is this part’s
function? The tubing represents the ureter, which are ther narrow tubes in the body.
The function of the ureter is that it carries urine from the kidney to the urinary bladder
2. What does the yellow food coloring represent at the end of the experiment? What
does the Congo Red represent?
The yellow food coloring represents glucose in the urine, while the congo red represnts
the proteins in the urine.
, Lab 14 The Urinary BIO202
L
System
Data and Observations
Record your observations as required by the experimental procedure in the table below.
Table 1: Solutions Present in Each Container Before 60 Minutes Submersion
Solution Dialysis Tubing Beaker
Congo Red Black None
Yellow Food Coloring Black None
Table 2: Solutions Present in Each Container After 60 Minutes Submersion
Solution Dialysis Tubing Beaker
Congo Red Red None
Yellow Food Coloring None Dark Yellow
Results and Discussion
1. Why is it important that the kidney filters the blood? In your response, discuss what
is being removed and what is being selectively retained.
It is important for the kidney to filter the blood because this process maintains the
body's internal balance(homeostasis) by removing harmful waste products and excess
subtstance while ratianing essential components. The kidney removes waste products
such as urea, creatinine, and excess salts on top of toxins and excess water. While at the
same time, it selectively retains important substances such as glucose, amino acids,
electrolytes, and water, depending on the body's current needs.This selective filtration
helps regulate blood pressure, maintain pH balance, and ensure proper hydation and
nutrient levels, which are all importnatn for overall health and homeostasis.
Straighterline
Student Name:
Access Code (located on the lid of your lab kit):
Lab Report Format Expectations
Utilize college level grammar and professional formaṄng when completing this worksheet.
Submissions without proper formaṄng, all required photos or sufficient responses will be
rejected. Pre- lab Questions
1. What is the function of the ureter?
The ureter is a tube that carries urine from the kidney to the urinary bladder. Each
kidney has one ureter. The urine is transported through peristaltic movement of the
smooth muscle in the ureter wall.
2. Compare and contrast the male and female urethra.
The male urethra is longer than the female urethra and serves a dual purpose, it carries
both urine and semen out of the body. It also passes through the prostate gland and
penis. While on the other hand, the female urethra is shorter and only serves to carry
urine. It opnes just above the vaginal opening.
3. Describe the two layers of the kidneys.
The kidney has two main layers: the cortex and the medulla. The cortex is the outer
layer and contains the glomeruli and most of the nephrons which filters the blood. The
medulla is the inner layer and is made up of renal pyramids, which contains the
collecting ducts that channel urine toward the renal pelvis.
,Lab 14 The Urinary BIO202
L
System
EXPERIMENT 1: KIDNEY FILTRATION
Introduction Questions
1. What specific part of the kidney does the dialysis tubing represent? What is this part’s
function? The tubing represents the ureter, which are ther narrow tubes in the body.
The function of the ureter is that it carries urine from the kidney to the urinary bladder
2. What does the yellow food coloring represent at the end of the experiment? What
does the Congo Red represent?
The yellow food coloring represents glucose in the urine, while the congo red represnts
the proteins in the urine.
, Lab 14 The Urinary BIO202
L
System
Data and Observations
Record your observations as required by the experimental procedure in the table below.
Table 1: Solutions Present in Each Container Before 60 Minutes Submersion
Solution Dialysis Tubing Beaker
Congo Red Black None
Yellow Food Coloring Black None
Table 2: Solutions Present in Each Container After 60 Minutes Submersion
Solution Dialysis Tubing Beaker
Congo Red Red None
Yellow Food Coloring None Dark Yellow
Results and Discussion
1. Why is it important that the kidney filters the blood? In your response, discuss what
is being removed and what is being selectively retained.
It is important for the kidney to filter the blood because this process maintains the
body's internal balance(homeostasis) by removing harmful waste products and excess
subtstance while ratianing essential components. The kidney removes waste products
such as urea, creatinine, and excess salts on top of toxins and excess water. While at the
same time, it selectively retains important substances such as glucose, amino acids,
electrolytes, and water, depending on the body's current needs.This selective filtration
helps regulate blood pressure, maintain pH balance, and ensure proper hydation and
nutrient levels, which are all importnatn for overall health and homeostasis.
