Chp 19 the Urinary System and Body Fluids

reabsorbed or unfiltered materials can be moved into the nephron by what process?

tubular secretion

produced by the liver during protein catabolism

urea

which system is responsible for long-term pH regulation?

urinary system

Fluid located between the cells in tissues is called

interstitial fluid

stimulates vasoconstriction

angiotensin

The water retaining hormone is __.

antidiuretic hormone

stimulates kidneys to produce concentrated urin

antidiuretic hormone

which of the following is an important buffer in body fluids?

bicarbonate

Body fluid percentages

blood plasma and lymph (skin, lungs, kidneys, intestine) 5% interstitial fluid (fluid between cells) 15% intracellular fluid (fluid inside cells) 40%

the body's hydrogen ion concentration is regulated by substances in body fluid called

buffers

produced by the kidney in response to low blood pressure

renin

Treatment of incontinence

- Approximately 80% of those affected by urinary incontinence can be cured or improved - Because incontinence is a symptom and not a disease, the method of treatment depends on diagnostic results - Types of treatment are behavioral, pharmacological, and surgical.

Kegel Exercises for the Pelvic Floor

- Pelvic muscles help stop the flow of urine. - For women, pregnancy, childbirth and being overweight can weaken the pelvic muscles. - For men, prostate surgery can weaken pelvic muscles. - Weak pelvic muscles can cause you to leak urine. - People who leak urine may have better control of these muscles by doing pelvic muscle exercises called Kegel exercises.

Urine

Liquid waste excreted by the kidneys

Urine Formation

1. Filtration: pressure pushes water and solute out of blood into bowman's capsule. It does this at a rate of 125 ml/min (180L/day) 2. Reabsorption: movement of substances in filtrate out of the tubules to the Para tubular capillaries & return to circulation 3. Secretion: substance move from the blood back into the nephron for excretion into the urine

How would decreased sodium and water in the interstitial fluid affect blood plasma? How would this change affect arterial blood pressure?

A decrease in sodium and water in the interstitial fluid would result in sodium diffusion from the blood into the interstitial fluid; water would soon follow. This movement of sodium and water would decrease the volume of plasma, and result in decreased arterial blood pressure.

What hormone besides aldosterone would be involved in maintaining water homeostasis?

ADH is secreted in response to decreased plasma volume; ADH increases the amount of water reabsorbed in the collecting ducts of kidney tubules, helping to restore plasma volume.

the hormone ___ is a salt and water losing hormone.

ANH

Micturition

Act of urination; voiding of the urinary bladder

Predict the changes that would occur in the urine of a runner who had just completed a marathon? How about a person who just ate a large bag of popcorn with extra salt?

After a marathon, it would be logical to predict that proteinuria would occur (protein in the urine). In addition, it would not be surprising for the runner to be dehydrated, and the amount of urine produced was less than normal. In the person that ate salty popcorn, with greatly increases salt intake, the person would have decreased salt reabsorption, and therefore a larger amount of salt excreted in the urine. Their urine would be saltier than normal.

Control of Urinary Volume

Aldosterone (adrenal cortex) - stimulates the kidney tubules to reabsorb more sodium - more water is then reabsorbed by osmosis - this reduces urin output, raises blood volume and raises blood pressure - this is a "salt and water" - retaining hormone ADH (antidiuretic hormone - from the posterior pituitary gland) - makes the distal convoluted tubule and collecting tubules more permeable to water - when ADH is present move water in reabsorbed, urine is more concentrated, and body fluid is conserved - "water retaining or urine decreasing hormone" - NO ADH is produced in the condition diabetes insidious so the body produces its of dilute urine ANH (Atrial Natriuretic hormone) - secreted by the heart cells when stretched by high blood pressure - ANH causes the kidneys to secrete more sodium and thus lose more water - inhibits ADH, aldosterone, and Renin secretion - overall effect is to lower blood volume and blood pressure - "salt and water losing hormone" Renin - a hormone secreted by the juxtaglomerular cells of the afferent arteriole in response to low blood pressure or a drop in blood sodium - stimulates production of angiotensin II in the blood which is a strong vasoconstrictor - angiotensin also stimulates aldosterone secretion to conserve sodium and water - both act to raise blood pressure

Explain the salt and water balance maintained by aldosterone and ADH.

Aldosterone is a hormone secreted by the adrenal cortex. It plays an important role in reabsorption of salt by the kidney tubules. Aldosterone also increases tubular water reabsorption. It is described as the water retaining hormone. ADH is present in blood from the posterior pituitary and is called antidiuretic hormone. It decreases the amount of urine by making the collecting tubules permeable to water.

1d.How would his body work to control his alkalosis and maintain homeostasis of the pH of his body fluids?

Because of the high altitude, respiratory control measures may not be effective because the low amount of oxygen diffusing into the blood could still result in hyperventilation. The kidneys would be the most important control mechanism; the kidney tubules would secrete fewer hydrogen ions into the urine and reabsorb fewer bicarbonate ions from the urine, thereby helping to decrease the pH of the blood to the normal range.

1a.A mountain climber, Justin, spent several days camped at a very high altitude on a mountain. He noticed he was breathing much faster than normal and he began to feel very nervous and excitable. Suggest a reason for his symptoms.

Because of the very high altitude, the amount of oxygen Justin was breathing was greatly decreased; the decreased oxygen in his blood continually stimulated his breathing, resulting in hyperventilation. Continued hyperventilation produces alkalosis when excessive amounts of carbon dioxide are removed from the blood. Symptoms of alkalosis include hyperactivity of the nervous system.

Interstitial

Between; pertaining to an organ's spaces or structures between active tissues; also refers to the fluid between cells

Major Ions

Cations Sodium - maintain osmotic balance and body fluid volume, main positive ion in extracellular fluids; maintain acid-base balance Potassium - transmission of nerve impulses; positive ion in ICF; involved in enzymatic activities Calcium - required for bone formation, muscle contraction, nerve impulse transmission, blood clotting Magnesium - muscle contraction; action of some enzymes Anions Bicarbonate - buffer in body fluids Chloride - essential formation of hydrochloric acid in the stomach; regulate fluid balance and pH; most abundant anion in extracellular fluids Phosphate - essential in carbohydrate metabolism, bone formation, acid-base balance; found in plasma membranes, nucleic acids (DNA, RNA), and ATP

Glomerulus

Cluster of capillaries surrounded by the kidney tubule's glomerular capsule

Bladder infection is referred to as __.

Cystitis

How would decreased arterial blood pressure affect aldosterone secretion? What would be the results of this change in aldosterone secretion?

Decreased arterial blood pressure results in increased aldosterone secretion. An increase in aldosterone secretion increases the amount of sodium reabsorbed into the blood from the kidney tubules; once again, water soon follows. As a result, blood sodium levels are restored, and blood volume is restored.

Other excretory system

Digestive system - eliminates water, some slats, and bile, in addition to digestive residue, all contained in the feces. Liver is important in eliminating products of red blood cell destruction and in breaking down certain drugs and toxins Respiratory system - eliminates carbon dioxide and small amounts of water. Integumentary system (skin) - excretes water, salts, very small quantities of nitrogenous wastes.

the last twisted segment of th renal tubule is called___

Distal convoluted tubule

Renin

Enzyme released from the kidney's juxtaglomerular apparatus that indirectly increases blood pressure by activating angiotensin

Glomerular filtrate

Fluid and dissolvent material hat leave the blood and enter the kidney tubule

Incontinence

Loss of bladder or bowel control Is a symptom - not a disease in itself. A broad range of conditions and disorders can cause incontinence - birth defects, pelvic surgery, injuries to the pelvic region or to the spinal cord, neurological diseases, multiple sclerosis, poliomyelitis, infection, and degenerative changes associated with aging. - It can also occur as a result of pregnancy or childbirth.

the network of blood capillaries located inside of Bowman's capsule is called ___

Glomerulus

Urinary bladder

Hollow organ that stores urine until it is eliminated

Antidiuretic hormone (ADH)

Hormone released from the posterior pituitary gland that increases water reabsorption in the kidneys, thus decreasing urinary output

Behavioral Techniques of Incontinence

Keep the pelvic floor muscles healthy through contraction Scheduled toileting - Visiting bathroom every 2-4 hours Bladder retraining - Gradually lengthening time between scheduled toileting Pelvic Muscle Rehabilitation - Involves pelvic muscle exercises alone or in conjunction with biofeedback therapy, vaginal weight training, pelvic floor stimulation, and magnetic therapy

The lithotripter is used to treat __.

Kidney stones

Main parts of Urinary system

Kidneys (2) - extract wastes from the blood, balance body fluid, from urine Ureters (2) - tubes conduct urine from kidneys to urinary bladder Urinary bladder - reservoir receives and stores the urine brought to it by the two ureters Urethra - tube conducts urine from bladder to the outside of the body for elimination

Nephron

Microscopic functional unit of the kidney; consists of the glomerulus and the renal tubule; maintain volume and composition of body fluids; also regulate pH and remove waste; done through urine formation

Anion

Negatively charged particle (ion)

Urea

Nitrogenous waste product excreted in the urine; end product of protein metabolism

How does the action of aldosterone and ADH affect urine volume and content?

Urine volume would decrease as a consequence of the action of aldosterone and ADH, the sodium content of the urine would decrease, and the potassium content of the urine would increase, because aldosterone also causes increased secretion of potassium into the kidney tubules.

Kidney

Organ of excretion, hormone synthesis, and blood pressure regulation

Extracellular

Outside the cell

If the kidney excretes an abnormally large amount of urine, the condition is referred to as __.

Polyuria

Cation

Positively charged particle (ion)

the movement of substances out of the renal tubules into the blood capillaries during the process of urine formation is called

Reabsorption

Changes in electrolytes or amount of fluid in the ICF or ECF affect every system in the body. Sometimes chemicals or infectious organisms can result in extreme irritation of the cells lining the large intestine. In response to this irritation, these cells may secrete sodium into the large intestine. Suggest the changes that would occur in the interstitial fluid if sodium were excreted from the intestinal lining into the large intestine.

Remember the statement "where sodium goes, water follows." If large amounts of sodium were present in the large intestine, water from the ICF of the intestinal cells would follows the sodium into the large intestines, producing diarrhea. If the ICF of intestinal cells had decreased sodium and water, then sodium would diffuse from the interstitial fluid into the ICF of the intestinal cells, and water would soon follow. Thus the interstitial fluid would have decreased amounts of sodium and water

Excretion

Removal and elimination of metabolic waste products from the blood

Tubular reabsorption

Return of substances in the glomerular filtrate to the circulation through the renal tubule

Angiotensin II

Substance produces from inactive precursors by the action of the renal enzyme renin and other enzymes; increases blood pressure by causing vascular constriction, simulating the release of aldosterone from the adrenal cortex and ADH from the posterior pituitary, and increasing thirst

pH

Symbol indicating hydrogen ion (H+) concentration; lower numbers indicate a higher H+ concentration and higher acidity

Osmolality

Term that refers to the solute concentration of a solution; osmotic concertation

1c.He took several antacid tablets, which contained sodium bicarbonate. Was this a good idea? How would this affect his alkalosis?

This was definitely not a good idea, because the increased sodium bicarbonate in his system would only serve to increase his alkalosis. His condition would probably worsen.

Name the three hormones that regulate the urine volume. State where each is made and the specific effect on urine volume.

Three hormones that regulate urine volume are 1) ADH, antidiuretic hormone from the posterior pituitary gland that decreases the amount of urine and thus reduces the amount of water loss by the body; 2) aldosterone, secreted by the adrenal cortex which stimulates the tubules to reabsorb sodium and water; 3) ANH secreted from the atrial wall of the heart that stimulates the kidney tubules to secrete sodium and lose water.

Ureter

Tube that carries urine from the kidney to the urinary bladder

Urethra

Tube that carries urine from the urinary bladder to the outside of the body

Types of Incontinence

Urge incontinence, or overactive bladder - Urgent need to pass urine and the inability to get to a toilet in time. - Occurs when nerve passages along the pathway from the bladder to the brain are damaged. Stress incontinence - Occurs when pelvic muscles have been damaged - Bladder leaks during exercise, coughing, sneezing, laughing, or any body movement which puts pressure on the bladder. Mixed incontinence - Occurs when symptoms of both stress and urge types are present. Overflow incontinence - Leakage that occurs when the quantity of urine produced exceeds the bladder's holding capacity. Fecal incontinence - Inability to control the passage or loss of gas, liquid and/or solid stool - Partial or complete

Urine passes from the bladder through the urethra to the exterior through an external opening called the __.

Urinary meatus

Excretory system

Urinary system; removal and elimination of unwanted substance from the blood

1b.He felt ill later on and vomited several times. How would this affect his alkalosis?

Vomiting produces metabolic alkalosis because of the loss of chloride ions from the stomach. Therefore, the alkalosis would increase, and his symptoms would probably become more severe.

Intracellular

Within a cell

produced by the kidney in response to hypoxia

erythropoietin

which structure is responsible for voluntary control of urination?

external urethral sphincter

what is the cluster of capillaries through which material enter the nephron tubule

glomerulus

the functional unit of the kidney is the

nephron

the medullar of the kidney can be subdivided into triangular areas called

pyramids

each kidney is located outside the abdominal cavity in the __space

retroperitoneal

which structure is responsible for evaporative water loss?

skin

the amount of dissolved substances in urine is indicated by its

specific gravity