Sheep Kidney Observation Lab
Name:
Class:
Date:_________________________
_
The human kidney anatomy is well equipped to perform all its crucial functions. The following kidney
diagram represents the structure of a kidney... sliced vertically.
KIDNEY ANATOMY
The kidneys are dark-red, bean-shaped organs. One side of the kidney
bulges outward (convex) and the other side is indented (concave). There
is a cavity attached to the indented side of the kidney, called the Renal
Pelvis... which extends into the ureter.
Each Kidney is enclosed in a transparent membrane called the renal
capsule... which helps to protect them against infections and trauma.
The kidney is divided into two main areas... a light outer area called the
renal cortex, and a darker inner area called the renal medulla. Within
the medulla there are 8 or more cone-shaped sections known as renal
pyramids. The areas between the pyramids are called renal columns.
Kidney Anatomy and Excretion
The most basic structures of the kidneys, are nephrons. Inside each kidney there are about one million of
these microscopic structures. They are responsible for filtering the blood... removing waste products.
The renal artery delivers blood to the kidneys each day. Over 180 liters (50 gallons) of blood pass
through the kidneys every day. When this blood enters the kidneys it is filtered and returned to the heart
via the renal vein.
The process of separating wastes from the body fluids and eliminating them, is known as excretion. The
body has four organ systems which are responsible for excretion. The urinary system is one of the organ
systems responsible for excretion. It excretes a broad variety of metabolic wastes, toxins, drugs,
hormones, salts, hydrogen irons, and water. The kidneys are the main organs of the urinary system.
Kidney Anatomy and Blood Vessels
The kidney is full of blood vessels. Blood vessels are integral to efficient kidney function. Every function
of the kidney involves blood, therefore, it requires a lot of blood vessels to facilitate these functions.
Together, the two kidneys contain about 160 km of blood vessels.
KIDNEY LOCATION
The normal kidney location is towards the back of the abdominal cavity, just above the waist. If you put
your hands on your hips, your kidneys are located just about where your thumbs are. One
kidney is normally located just below the liver, on the right side of the abdomen and the other is
just below the spleen on the left side. In rare cases, however, one or both kidneys may be
located much lower in the abdomen. This is not necessarily a problem except probably in the
case of pregnancy. As the fetus begins to develop in the womb this could sometimes place
pressure on the kidney which is located in the lower abdomen.
NORMAL KIDNEY SIZE
The normal kidney size of an adult human is about 10 to 13 cm (4 to 5 inches) long and
about 5 to 7.5 cm (2 to 3 inches) wide. It is approximately the size of a conventional
computer mouse. A kidney weighs approximately 150 grams. Kidneys weigh about 0.5
percent of total body weight.
Sheep Kidney Size ________________
Mass of Sheep Kidney: ____________
How does the sheep kidney size and mass compare to an adult human kidney?
Internal Kidney Structures
Using the sheep kidney specimens, locate each of the following internal parts of the
kidney and color-code them with the labels to the right.
Now raise
your hand
and have
your
teacher
come over
and let you
identify
these parts
on the
specimen:
Teacher
initials:
Identify that Value!
Fill in the left hand column with the terms/values from the list: 15%; thirst; 66%; 80%; kidneys;
hypothalamus
The proportion of the body’s water found within the cells
The part of the brain concerned with controlling water
balance
The proportion of the body’s water an animal will not
survive losing
This is the main mechanism for diluting the blood
The proportion of an animal’s body that consists of water
These organs are important for controlling water balance
MATH CHALLENGE (Show your Work!)
The kidneys are almost as busy as the heart! They process 45 liters of blood per day and remove
about 1.5 liters of waste per day. Over a lifetime that can really start to add up.
1) What if you wanted to find out how many liters of blood the kidneys processed in one year?
2) What if you wanted to find out how many liters of waste the kidneys removed in one year?
3) What if you lived to be one hundred years old? How many liters of blood will your kidneys
have processed?
4) What if you lived to be one hundred years old? How many liters of waste will your kidneys
have removed?
Review Questions - Answer in complete sentences.
1.
What are the two primary functions of the kidneys?
2. Which blood vessel, the renal artery or renal vein contains less nitrogenous wastes such as urea?
Explain why.
3. Which blood vessel, the renal artery or renal vein carries more oxygen? Explain why.
4. What do you think is the function of the adipose tissue around the kidney?
5. What structure allows the urine to flow from the kidney to the urinary bladder?