Essentials of Anatomy and Physiology

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CHAPTER 18

Chapter Outline

Kidneys
Internal Structure of the Kidney
The Nephron
Renal corpuscle
Renal tubule
Blood Vessels of the Kidney
Formation of Urine
Glomerular Filtration
Tubular Reabsorption
Mechanisms of reabsorption
Tubular Secretion
Hormones That Influence Reabsorption of Water
Summary of Urine Formation
The Kidneys and Acid–Base Balance
Other Functions of the Kidneys
Elimination of Urine
Ureters
Urinary Bladder
Urethra
The Urination Reflex
Characteristics of Urine
Aging and the Urinary System

BOX18–1 FLOATING KIDNEY

BOX18–2 RENAL FAILURE AND HEMODIALYSIS

BOX18–3 ERYTHROPOIETIN

BOX18–4 KIDNEY STONES

BOX18–5 BLOOD TESTS AND KIDNEY FUNCTION

BOX18–6 URINARY TRACT INFECTIONS

Student Objectives

• Describe the location and general function of each
  organ of the urinary system.


• Name the parts of a nephron and the important
  blood vessels associated with them.


• Explain how the following are involved in urine
  formation: glomerular filtration, tubular reabsorp-
  tion, tubular secretion, and blood flow through the
  kidney.


• Describe the mechanisms of tubular reabsorption,
  and explain the importance of tubular secretion.


• Describe how the kidneys help maintain normal
  blood volume and blood pressure.


• Name and state the functions of the hormones
  that affect the kidneys.


• Describe how the kidneys help maintain normal
  pH of blood and tissue fluid.


• Describe the urination reflex, and explain how vol-
  untary control is possible.


• Describe the characteristics of normal urine.