Introduction toWord Parts andWord The Urinary System Lesson Plan Chapter 11

The urinary system functions as the sanitary engineer of the body, maintaining the purity and health of the body’s fluids by removing unwanted waste materials and recycling other materials. Its organs consist of:

• Filtration of gallons of fluid from the bloodstream every day.

• Removal of metabolic wastes, toxins, excess ions, and water that leave the body as urine, in a function known as excretion. Urine—which is mostly water, excess electrolytes and metabolic waste material, urea, and ammonia—formation occurs in three stages within each of the nephrons:

• Filtration—The filter is a very thin membrane between the wall of the glomerulus and the inner wall of the Bowman’s capsule. As blood pressure pushes blood through the glomerulus, some of the blood’s plasma is forced through tiny openings in the membrane, filling the Bowman’s capsule with fluid.

• Reabsorption—As fluid flows through the renal tubule, most of the water is reabsorbed back into the bloodstream.

• Secretion—Excess electrolytes (salts in an ionic form) and other waste are transported into the renal tubule.

• Returns needed materials back to the blood.

• Regulates blood pressure, pH, and red blood cell production in bone marrow.

Parts of the kidneys are as follows:

• Hilum—the concave margin where the renal artery, renal veins, nerves, and ureter join the kidney

• Renal pelvis—a membrane-lined basin that collects urine in the center

• Renal medulla—lies external to the pelvis

• Cortex—the outermost area of the kidney

• Nephrons—located in the renal medulla and cortex, they amount to about one million in number, and each has the following:

• Bowman’s capsule—a tube that consists of a hollow ball at one end

• Renal tubule—a long twisted portion at the other end

• Glomerulus—a tightly coiled capillary located within the Bowman’s capsule. This structure, together with the Bowman’s capsule, makes up the renal corpuscle.

2. Ureters—a pair of spaghetti-sized organs that transport urine from the kidneys to the urinary bladder

• They arise from the renal pelvis and extend downward along each side of the vertebral column until they unite with the bladder.

• Their walls consist of:

• The inner mucous membrane—protects the ureter from potentially damaging effects of urine.

• The outer layer of smooth muscle—provides waves of peristalsis that help propel the urine along its way to the urinary bladder.

3. Urinary bladder—a hollow, muscular organ located at the floor of the pelvic cavity that temporarily stores urine. The interior of the urinary bladder has openings for the two ureters and the single urethra. These three openings form a triangular region known as the trigone, which is a frequent site of urinary infection. The bladder is lined with an elastic mucous membrane, and the outer wall is composed of involuntary muscle that contracts during urination.

4. Urethra—a muscular tube that drains urine from the floor of the urinary bladder and transports it to the exterior. The urethra is lined internally with a protective mucous membrane. The release of urine through the urethra is called micturition, or voiding. The urethra consists of the:

• Internal urethral sphincter—a thickening of muscle at the junction between the bladder and the urethra

• External urethral sphincter—muscle that is under voluntary control that surrounds the urethra at the point where it extends through the floor of the pelvic cavity

• External urethral orifice, or urinary meatus—the opening to the exterior or outside the body.

The urethra differs between males and females:

• Females—about 3 to 4 cm (1.5 inches) long and bound to the vaginal wall by connective tissue. The urinary meatus lies between the vagina and the clitoris.

• Males—about 20 cm (8 inches) long and extends from the urinary bladder to the end of the penis, where it opens as the urinary meatus. As it leaves the bladder, the male urethra passes through the prostate gland that surrounds it.

Review an actual urinalysis report in class.

Invite a urologist to class to speak about the components of the urinary system.

Urethral cancer is an extremely rare form of cancer (only about 700 cases reported worldwide). Cancer develops in the urethra as the result of abnormal cell growth within the urethra.

Approximately 440 gallons of blood flow through the renal arteries to be filtered by normal-functioning kidneys every day.

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  Explain the composition of urine, and discuss how much information can be gained about a patient’s state of health by performing a simple urinalysis.
  

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  Don’t let students think that excreting waste is the only thing the kidneys do. Explain how the kidneys are active in regulating blood pressure, blood pH, and the number of RBCs.
  

A kidney donor’s health is not affected by losing one kidney. The remaining kidney enlarges to take over almost full function.

Visual learners will benefit from watching an animation of the urinary system.

Visual learners will benefit from watching an animation of the kidneys.

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  Try to obtain an actual kidney stone, and pass it around for the students to examine. Point out the sharp edges and the shape, which are what cause pain as the stone is being passed.
  

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  Introduce the basic anatomy and physiology of the urinary system through labeling and coloring of the kidney, ureters, bladder, and urethra.
  

Have students complete the Phonetic Spelling Challenge and the Spelling Challenge in Worksheet 1.

Study the pronunciation for medical terms in this chapter in the:

• Text in parentheses following the term

• Glossary at Medical

Make abbreviation flash cards. Shuffle them, and place them facedown on a table. Have students randomly make selections, and provide the class with the meaning.

Ask the students to point on their own bodies to the place where kidney pain is likely to occur (lower back at the waistband, to the right and left of the spine). With what might pain here be confused? (Low back pain; muscular.)

• The urinary system and the male reproductive system share some organs, particularly the urethra. The term genitourinary (GU) is sometimes used to describe the urinary system.

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  The kidney is shaped like a kidney bean. Each weighs 4 to 6 ounces and is 2 to 3 inches wide and about 1 inch thick, or about the size of a fist. Functioning kidneys are needed for life, but it is possible to live with only one functioning kidney.
  

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  Medical Terminology Bee: Create PowerPoint flash cards of new combining forms and suffixes presented in this chapter. Have all students stand, and ask one to define the word part. If the student is correct, he/she remains standing. If the student is wrong, he/she sits down. Continue until only one student is standing.
  

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  Visual learners will benefit from watching the video on the topic of urinalysis .
  

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  Visual learners will benefit from viewing a video on the topic of renal failure.
  

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  Note that ur/o and -uria are two of the most important word parts in this chapter.
  

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  Explain how the kidneys not only filter the blood and create urine, but also secrete a hormone—erythropoeitin—that signals the bone marrow to make more red blood cells when their level becomes low.
  

The root noct/o occurs in nonmedical terms as well. Example: Nocturnal animals (animals that are awake at night).

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  Explain the differences between the male and female urinary systems. Explain how the male shares structures with both the reproductive system and the urinary tract. In the male, the system is referred to as the genitourinary or urogenital system.
  

Dissect medical terms into their component roots, prefixes, and suffixes as you introduce them.

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  Challenge students to “invent” some other types of uria’s by combining this suffix with roots from other chapters. Encourage them to get as silly as possible!
  

1. Who is most prone to have kidney stones?

2. What preventive behaviors can you begin to avoid urinary system disease?

3. You can live with only one kidney. Under what conditions would you consider donating a kidney, and why?

4. What is the action of cranberry juice on the kidneys? If an individual with a UTI feels better after drinking cranberry juice, does that person still need to take an antibiotic?
Teaching Tips

Explain the composition of urine, and discuss how much information can be gained about a patient’s state of health by performing a simple urinalysis.

The term calculus means “pebble” in Latin. In medicine, a calculus is a stone somewhere in the body. The term calculus also is used as a name for a particular branch of advanced mathematics. What’s the connection? In ancient times a small stone was used to assist in mathematical calculations.

Try to provide as many images as possible so that students can really visualize the disorders and procedures you are discussing.

Have students complete the Word Search in Worksheet 1.

• Text in parentheses following the term

• Glossary at Medical

Terminology Interactive

Present an unlabeled diagram of the urinary system. Have students select printed labels from a box and assign them to the correct anatomy, describing the function of the part.

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  Encourage/remind students to add new word parts to flash cards.
  

When discussing the anatomy and physiology of the urinary system, try to obtain a beef kidney to dissect so that the internal structures can be revealed and studied.

The urinary bladder contains almost no bacteria.

• 
  Dissect medical terms into their component roots, prefixes, and suffixes as you introduce them.
  

Divide the class into groups, assign a disease to each group, and have each write a case study created from word parts that students have already learned.

Have students complete the True/False, Fill in the Blank, and Short Answer sections of Worksheet 1.

• Text in parentheses following the term

• Glossary at Medical

Terminology Interactive

Invite a registered dietitian to talk about the correlation of diet and kidney health.

Ask the students to create a concentration game from urinary system terms and abbreviations.

Encourage students to learn more about dietetics by visiting the following Websites:

• American Academy of Nutrition at www.nutritioneducation.com

• American Dietetic Association at www.eatright.org

• Society for Nutrition Education at www.sne.org
Have the students construct sentences using abbreviations.

Abbreviation	Meaning
BUN	blood urea nitrogen
cath	catheter, catheterization
HD	hemodialysis
IVP	intravenous pyelogram
RP	retrograde pyelogram
SG	specific gravity
UA	urinalysis
UTI	urinary tract infection
VCUG	voiding cystourethrogram

Teaching Tips

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  Students often confuse the ureters with the urethra. Emphasize the difference between these sound-alike words.
  

• With age, the urinary bladder shrinks and loses some of its ability to contract and relax. As a result, older people must go to the bathroom more often.

• By 70 to 80 years of age, most people have 50% fewer nephron units and so are less able to concentrate urine.
Teaching Tips

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  Write sentences on the board using common words. Have students substitute the correct medical terms.
  
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  Emphasize to students the importance of correctly spelling terms and how sounding out terms can assist in learning how to spell the terms.
  

Have students make word part flash cards using index cards. One word part should be placed on each card. Challenge the students to include a doodle that helps them picture the word.

Also, have students use index cards to make flash cards for important muscle diseases and procedures. Encourage students to use pictures rather than lengthy definitions on these flash cards.
Teaching Tips

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  Say each new term in class and have the students repeat it.
  

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  Jeopardy game: Have students create questions for terms in this section for a Jeopardy game to be played in class
  
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  Select two students to do 5-minute presentations of their Internet research in class.
  

1. Women are more prone to urinary tract infections (UTIs) than are men. Why do you suppose that is?

2. What preventive measures can women take to avoid urinary tract infections?

3. What types of disorders can a urinalysis help us diagnose? Are any of these disorders outside the urinary system?

4. Do you think there are any differences between the male and female urinary systems? If so, what are they?
Did You Know?

Glomerulus comes from a Latin word meaning “ball of yarn” and gets its name because the glomerulus’s network of intertwining capillaries resembles a ball of yarn.
Homework Assignments

Students complete the Abbreviation Matchup in Worksheet 1.

• Text in parentheses following the term

• Glossary at Medical

Terminology Interactive

Worksheet 1: Chapter Review

Worksheet 2: Dictation Report

Worksheet 3: Word Surgery

Worksheet 4: Case Study

Worksheet 5: Medical Report Analysis

Worksheet 6: Which Term Does Not Belong?

Worksheet 7: Labeling