THE URINARY SYSTEM

Chapter 29A&P

OBJECTIVES

Describe the purpose and function of the urinary system

Identify the organs and the function of each List 3 processes involved in the production of

urine Normal constituents of urine. Common disorders Lifespan considerations Case study

INTRODUCTION

The urinary system consists of organs that produce and excrete urine from the body.

Urine contains waste: mostly excess water, salts and nitrogen compounds.

Primary organs are the kidneys Normal adult bladder can store up to .5 liters. Also responsible for regulating blood volume

and blood pressure. Regulates electrolytes.

ORGANS OF THE URINARY SYSTEM

The components of the urinary system include :

the kidneys the ureters the urinary bladder the urethra.

MALE URINARY SYSTEM

KIDNEYS The kidneys are bean-

shaped organs located at the back of the abdominal cavity.

They lie on either side of the spinal column.

This area is known as the flank area and is against the muscles of the back.

The external kidney has a notch at the concave border known as the hilum.

The hilum is the entrance for renal artery, veins, nerves and lymphatic vessels.

INTERNAL STRUCTURE OF THE KIDNEY

The cortex is the outer layer; arteries, veins, convoluted tubes and glomerular capsules

The medulla is the inner layer; renal pyramids

NEPHRONS

1 million nephrons The functional unit

of the kidney Remove waste

products of metabolism from the blood plasma.

Waste products are urea, uric acid, creatinine, sodium, potassium chloride and ketone bodies.

URETERS, BLADDER AND URETHRA Ureters -tubes that

carry newly formed urine from the bladder to the kidneys.

Bladder-muscular sac that serves as a reservoir for urine; bladder stretches to accommodate urine.

Urethra- tube extends from the bladder to the external opening of the urinary system, the urinary meatus

URINE

The formation of urine has 3 processes, filtration, reabsorption and tubular secretion.

Urine consists of 95% water and 5% solid substances.

The need to urinate is usually felt at 300-350ml of urine in the bladder.

Typically 1000-1500 mL is voided daily. Observations of urine?

COMMON DISORDERS

Cystitis- inflammation of the bladder “honeymoon disease”

Glomerulonephritis- a type of kidney disease Incontinence- stress, urge, overflow, functional,

reflex and mixed Kidney stones- renal calculi caused my mineral

salt deposits in the kidneys Polycystic kidney disease- cysts develop in the

kidneys Pyelonephritis- infection of the kidney and renal

pelvis. Renal Failure- kidney do not function as they

should

LIFESPAN CONSIDERATIONS

Child At 10 weeks

gestation the kidney begin to form

Newborns kidneys are not able to concentrate urine

Kidneys are more susceptible to trauma

Diapers- more susceptible to UTI

Older Adult Kidney lose mass and the

blood vessels degenerate Kidneys lose their ability

to filter Dehydration can happen

more quickly Electrolyte balance

happens more quickly Loss of muscles tome in

urinary structures Decreased bladder

capacity

CASE STUDY

What substance was found in his urine?

If he could not pass the kidney stone, what treatment would have to be done?

What types of dietary restrictions should be followed?

THE FAR SIDE