A&P II Unit 4  

Stretch receptors

Distension of the bladder while filling stimulates _________ in the bladder wall which sends impulses to the spinal cord resulting in a reflex action which keeps the sphincter muscles closed

Large proteins

During glomerular filtration all solutes except _______ leave the blood and enter the Bowman's capsule

Tubular secretion

Elimination of material not filtered out

Excretion

Elimination of metabolic wastes (urea)

Egestion

Elimination of undigested food

Active transport

Energy is required to reabsorb materials that are more concentrated in the blood than in the filtrate

Carbonic acid

Excess carbon dioxide in the blood may enter the kidney tubular cells where it combines with water to for __________ which dissociates into bicarbonates and HYDROGEN ions which then are released into the urine where they are "buffered" by phosphates

Effective filtration pressure

Sum of pressure favoring filtration in capillaries

Peritubular capillaries

Surround the tubules of CORTICAL nephrons

Boman's capsule

Surrounds the glomerulus in the nephron unit

Tubular reabsorption

Selective reuptake of nutrients, electrolytes, etc

Ascending

Sodium is reabsorbed in the _____ branch of the loop of Henle

Glomerulus

Special capillary bed between two ARTERIOLES; it is a high-pressure system because of the SHORT afferent arteriole leading into it; serves as the major site of filtration of the blood in the kidney

Medulla

The ______ of the kidney is composed mostly of collecting ducts and some loop of Henle; triangular-shaped RENAL PYRAMIDS make up the bulk

Glomerular filtration rate

The amount of filtrate produced per minute

Glycogenolysis

The breakdown of glycogen to glucose

Hydonephrosis

The buildup of water or urine in the kidney; kidney stones may block the passage of urine and cause backup of urine into the kidney

Detrusor

Muscle that forms most of the upper wall of the body of the URINARY BLADDER

Peristaltic waves

Movement of urine down the ureter occurs due to gravity and _______

External urethral sphincter

Muscle composed of skeletal muscle and is under voluntary control (D); found between the urethra and the body wall

Internal urethral sphincter

Muscle composed of smooth muscle and is under involuntary/autonomic control (C)

Urochrome

A bile pigment found in urine which is a waste product formed during the destruction of HEMOGLOBIN; yellow color of urine is due to

Respiratory acidosis and metabolic acidosis

Adjustments to the acid-base balance made by the kidney help to "compensate" for

Gluconeogenesis

Among the functions of the kidney is ___________ which is the production of CARBOHYDRATES (glucose) from non-carbohydrate courses such as amino acids and fatty acids

Osmotic diuresis

An increase in urine output due to excess glucose in the urine

Diuresis

An increase in urine output; may be due to a DECREASE in the antidiuretic hormone released by the POSTERIOR pituitary

Increase

An increased blood volume will result in a __________ in blood pressure

Cystitis

An infection of the urinary bladder

20

Approximately ____ percent of cardiac output enters the renal circulation

More

As the filtrate moves down the loop of Henle it becomes ______ concentrated

Less

As the filtrate moves up the loop of Henle it becomes _____ concentrated

The blood pressure is higher in the glomerulus than in other capillary beds

Because the relative short arteriole (afferent) entering the glomerulus; the constriction of the efferent arteriole, and constriction of afferent arteriole

Shorter

Bladder infections are more common in females than in males because the urethra is

Renal fascia

Covers the kidneys along with renal fat capsule which holds them in position and attached the kidney to surrounding structures

Creatine

Muscle deterioration is noted by increased amounts of ______ in the urine

Urination

Formation of urine

Juxtaglomerular apparatus

Formed by the AFFERENT arteriole and the NEPHRON TUBULE; formed where the afferent arteriole comes into contact with a convoluted tubule (proximal or distal); produces and secretes RENIN

Male urethra

Functions in both micturition and reproduction and is longer than the female urethra; consist of three regions: prostatic, membranous, and spongiosum

Sodium

Glucose, other nutrients, and most solutes are reabsorbed via co-transport with _____ in the proximal convoluted tubule

Proximal convoluted tubule

Has a "brush-border" epithelium--microvilli that increase the surface area for reabsorption; the MAJOR site of tubular reabsorption (reabsorption of solutes)

Kidney

Highly metabolic organ which requires rich blood supply; approximately 1/4 of the cardiac output passes through the kidney per minute

Renin, erythropoietin

Hormones produced and secreted by the kidneys

Aldosterone

INCREASES the reabsorption of sodium in the ascending loop of Henle AND distal convoluted tubule and thus INCREASES water reabsorption thereby INCREASING blood volume--produced and secreted by the ADRENAL CORTEX

Ascending loop of Henle

Impermeable to water but permeable to solutes; primarily involved in the reabsorption of sodium

Uric acid

In humans, comes from the metabolism of nucleic acid such as DNA and RNA

Antidiuretic hormone

Increases the reabsorption of water in the collecting duct; secreted by the hypothalamus/posterior pituitary

Aldosterone

Increases the sodium channels, increases the production of sodium/potassium pumps, and increases energy production

Pyelitis

Infection of kidney/ureter

Urethritis

Infection of the urethra

Facilitated diffusion

Initially most solute molecules are reabsorbed as they move from an area of high concentration to an area of lower concentration using carrier molecules

myogenic, tubuloglomerular, renin-angiotensin mechanisms

It is very important to maintain the proper pressures in the glomerulus, thus there are several mechanisms for maintaining glomerular filtration

Proximal convoluted tubule

Link the Bowman's capsule to the loop of Henle; primarily involved the reabsorption of nutrients

Distal convoluted tubule

Link the loop of Henle to the collecting ducts; primarily involved in tubular secretion

Myogenic mechanism

Low blood pressure results in a decreased stretching of vessel walls causing a reflex of vasoconstriction which will then increase blood pressure

Tubuloglomerular mechanism

Low blood pressure will result in decreased filtrate flow and results in the MACULA DENSA releasing ATP which causes vasoconstriction and thus raise the blood pressure

Water

Main component of urine

Specific gravity

Measurement that is used to determine the CONCENTRATION OF SOLUTES in the urine

Diuretics

Medications that are taken to increase urine output

Cortical

Most nephron units are ______ nephrons which means that the loop of Henle is SHORT and REMAINS in the cortex

Ureter

Muscular duct connecting the kidney to the urinary bladder; enters the kidney at the HILUM and expands into the funnel-shaped RENAL PELVIS; inner lining consists of transitional epithelium which allows for expansion

Urethra

Muscular duct connecting the urinary bladder to the outside

Hydrogen ions, urea, drugs

Normally secreted into the urine

Spongy urethra

Passes through the penis of a male

Descending loop of Henle

Permeable to water but impermeable to solutes

Angiotensin

Powerful VASOCONSTRICTOR and also INCREASES the production and secretion of ALDOSTERONE by the adrenal cortex

Pyuria

Presence of WBC's (pus) in the urine--would indicate a bacterial infection

Collecting duct

Primarily involved in completing the reabsorption of water

Carrier-mediated transport

Reabsorption of MOST solutes occurs through

Vasa recti

The capillaries surrounding the loop of Henle of juxtamedullary nephrons (descending and ascending ducts) are termed; Reabsorption is facilitated here because the blood and filtrate flow in OPPOSITE directions (counter-current mechanism)

Podocytes

The endothelium of the Bowman's capsule is composed of ______ --special cells of the Bowman's capsule, which wrap around the glomerular capillaries

Renal pelvis

The expanded end of the ureter inside the kidney; the ureter enters the kidney and expands into a funnel shaped pelvis which collects urine from the collecting ducts

Prostate gland

The first portion of the male urethra is surrounded by the; the first region of the male urethra attached to the urinary bladder is known as the prostatic urethra because it passes through the

Increase

The kidney helps regulate the acid/base balance. An increase in blood CO2 results in carbon dioxide moving into the tubular cells, combining with water forming carbonic acid which dissociates into bicarbonates and hydrogen ions, The bicarbonates move back into the blood and buffer hydrogen ions in the blood, while the hydrogen ions move into the urine and combine with phosphates. Thus the pH of the blood will ________--become less acidic

Vitamin D

The kidney metabolizes _______ to its active form calcifeol which is needed for the absorption of CALCIUM

Retroperitoneal

The kidneys are said to be _________ since they lie against the dorsal abdominal wall behind the PARIETAL peritoneum

Renin-angiotensin mechanism

The major mechanism of control; low blood pressure causes the juxtaglomerular apparatus to release RENIN which converts a plasma protein to ANGIOTENSIN, Angiotensin II stimulates the adrenal CORTISOL to produce ALDOSTERONE which increases in reabsorption of SODIUM in the ascending loop of Henle resulting in an increase in blood pressure

Urea

The major nitrogenous waste product in urine in humans; most common solute in urine

Filtration

The movement of molecules through a porous membrane due to a difference in PRESSURE

Cortex

The nephron units are primarily located in the ______ of the kidney; outer portion of the kidney

Glycosuria

The presence of glucose in the urine

Ketonuria

The presence of ketone bodies in the urine which suggested the breakdown of FAT to produce fuel molecules

Creatinine

The result of breakdown of proteins

Trigone

The triangular area at the base of the urinary bladder where the ureter and urethra are connected

Renal fat capsule

Tough, fibrous connective tissue that surrounds the kidney, protection of the kidney from blows to the back is furnished by the

Ureter and urinary bladder

Transitional epithelium lines the

Acidic

Urine is normally more _____ than blood

Micturition

Voiding of urine

Parasympathetic reflex

When convenient, ________ beginning in the pons causes contraction of the DETRUSOR muscle of the bladder and the relaxation of EXTERNAL urethral sphincter muscles

Reabsorbed

When determining the GFR, a substance that is not normally _______ is injected into the blood and following a period of time its concentration in the blood when injected is divided by its concentration in the URINE

Ptosis

When the attachments (renal fascia and renal fat capsule) become weak so the kidney descends in the abdominal cavity causing a "kink" in the ureter; "fallen kidney"