A&P Exam Urinary System CH 20 Flashcards
What are the functions of the urinary system?
- Filtration of blood
- Formation of urine
- Transportation of urine from kidneys to urinary bladder
- Collection and storage of urine
- Conveys urine from urinary bladder to outside of body
What are the major organs of the urinary system?
Kidneys
Ureters
Urinary bladder
Urethra
What is the function of the kidneys?
Filtration of blood and formation of urine
What is the function of the ureters?
Transportation of urine from kidneys to urinary bladder
What is the function of the urinary bladder?
Collection and storage of urine
What is the function of the urethra?
Carrying of urine from urinary bladder to outside the body
The kidneys contribute to homeostasis as _______ organs
Excretory
The kidneys maintain the _________, ____, and ______ of body fluids within normal limits.
Composition; pH; volume
The kidneys remove metabolic wastes and substances present in __________, including foreign substances like drugs and their toxic metabolites
Excess
The kidneys secrete _________ that regulate specific metabolic processes
Hormones
The kidneys regulate volume and composition of body ______
Fluids
The kidneys remove excess _____, ________, and ________ from the blood
Water; electrolytes; metabolic wastes
The kidneys excrete wastes in the ______
Urine
The kidneys secrete the hormone ___________, which stimulates red blood cell production
Erythropoietin
The kidneys secrete the enzyme ________, which helps to increase blood pressure
Renin
The kidneys produce the active form of Vitamin D (_________), which increases calcium absorption from the small intestine when blood calcium level is low.
Calcitriol
When the kidneys are not functioning properly, hemodialysis and ________________ can be used to filter wastes out of the blood
Continuous peritoneal dialysis
What are the three protective tissue layers that protect the kidneys?
Fibrous renal capsule
Adipose tissue (renal fat)
Connective tissue (renal fascia)
The kidney has a __________ surface, and a __________ surface
Convex lateral; concave medial
Hollow chamber in medial depression of kidney
Renal sinus
Outer region of kidney
Renal cortex
Inner region of the kidney, composed of the renal pyramids
Renal medulla
The extensions of the cortex that dip into the medulla of the kidney
Renal columns
The entrance to the renal sinus
Hilum
The funnel-shaped sac of the kidney; superior to the end of the ureter
Renal pelvis
What are the two components of the renal pelvis?
Major calyces
Minor calyces
Large tubes that merge to form the renal pelvis
Major calyces
Small tubes that merge to form the major calyces of the renal pelvis
Minor calyces
The fibrous capsule around the kidney
Renal capsule
The functional units of the kidneys, each of which is a site of urine production
Nephrons
Expulsion of urine from the urinary bladder
Micturation (urination)
Urine leaves the urinary bladder by the __________
Micturition reflex
How does the micturition reflex occur?
Reflex contraction of detrusor muscle and reflex relaxation of the internal urethral sphincter
The micturition reflex requires relaxation of the ___________ sphincter
External urethral
The urinary bladder may hold up to _____ mL of urine; the urge to urinate starts when it contains about ____ mL
600; 150
Micturition is controlled by the __________ center in sacral spinal cord
Micturition reflex
What are the two problems most commonly associated with micturition?
Incontinence and nocturnal enuresis
Inability to control micturition
Incontinence
Bedwetting is also known as
Nocturnal enuresis
What generally causes incontinence?
Loss of bladder control, bladder holding less urine due to age, loss of elasticity in tissues
What generally causes involuntary urinary retention?
An obstruction or narrowing in or around the bladder, or when muscles around the bladder are weak. Certain type and locations of tumors, certain medications, being dehydrated, or having constipation.
Is urinary retention more common in women or men?
Men. This is due to a blockage that can be caused when the prostate gland gets so big that it presses on the urethra; women do not have a prostate gland.
Why would urinary retention occur in females?
Due to problems with the nerves that control your bladder. This can happen as a result of diabetes, stroke, multiple sclerosis, brain or spinal cord infections or injuries, or pelvic injury.
Why does incontinence occur in men?
Incontinence in men is often related to prostate problems or treatments. Drinking alcohol can make it worse. Prescription drugs as well.
Why does incontinence occur in women?
Pelvic floor trauma with childbirth, menopause, hysterectomy, obesity, cognitive impairment, chronic cough and constipation.
The perineal nerve is the largest ________ branch of the pudendal nerve
Terminal
Why is the perineal nerve important?
It controls your pelvic floor muscles and your urethral sphincter. It also provides sensory information to the perineum and the labia.
What were to happen if the perineal nerve was damaged?
Pain, numbness, and dysfunction in the genitalia, perineum, rectum, and lower urinary tract
Site of urine production; functional units of the kidney
Nephrons
From the ______, blood flows into the renal vein and leaves the kidney
Nephron
What are the two parts of the nephron?
Renal corpuscle and renal tubule
The renal corpuscle of a nephron consists of a _______ and a __________; the site of blood filtration in the kidney.
Glomerulus; glomerular capsule
What are the two types of nephrons in the kidney?
Cortical nephrons and juxtamedullary nephrons
Majority of types of nephrons?
Cortical nephrons
Where are cortical nephrons located?
Almost completely in the renal cortex
Cortical nephrons have short _________ loops
Nephron
What makes up the smaller percentage of nephrons?
Juxtamedullary nephrons
Juxtamedullary nephrons have long nephron _______ that extend deep into the medulla
Loops
The renal corpuscles of cortical nephrons are located near the ______ of the kidney
Surface
The renal corpuscles of juxtamedullary nephrons are located deep in the renal _______
Cortex
________ nephrons are important in regulating water balance and urine concentration
Juxtamedullary
What is the juxtaglomerular complex/apparatus?
A structure in the kidney that regulates the function of each nephron.
The juxtaglomerular apparatus regulates the secretion of the enzyme ______
Renin
The juxtaglomerular apparatus monitors and adjusts blood pressure and _______ content of filtrate
NaCl (sodium chloride)
Where the the juxtaglomerular apparatus located?
Where the ascending limb of the nephron loop passes between the afferent and efferent arterioles
Afferent arteriole
Ascending limb of the nephron loop
Descending limb of the nephron loop
Distal convoluted tubule
Efferent arteriole
Glomerular capsule
Glomerulus
Nephron loop
Proximal convoluted tubule
Renal corpuscle
Renal tubule
The glomular capsule is also known as the _________ capsule
Bowman’s
Collecting duct
Peritubular capillary
What is the pathway of urine formation through a nephron?
Afferent arterioles
Glomerulus
Glomerular capsule
Proximal tube
Nephron loop (descending limb
Nephron loop (ascending limb)
Distal tubule
What are the three processes of urine formation?
Glomerular filtration
Tubular reabsorption
Tubular secretion
Glomerular filtration is performed by specialized ____________ (first capillary bed)
Glomerular capillaries
During glomerular filtration, water and small molecules are filtered ______ of blood and _______ renal tubules
OUT; INTO
During glomerular filtration, filtered fluid enters the renal tubules and becomes _______ (which eventually becomes urine)
Tubular fluid
During tubular reabsorption, selected substances move ______ renal tubules _______ peritubular capillaries (secondary capillary bed)
FROM; INTO
Tubular reabsorption is how the body _________ useful substances, while wastes continue through the renal tubules to eventually become urine.
Reclaims
Tubular secretion is the movement of certain substances (such as toxins, ions, etc.) ____________ peritubular capillaries _______ renal tubules to be disposed of in urine.
Out of/from; INTO
Tubular secretion adds waste products and excess substances to form _______
Urine
Process of urine formation that filters Water and small molecules are filtered OUT of blood INTO renal tubules.
Glomerular filtration
Process of urine formation during which Selected substances move FROM renal tubules INTO peritubular capillaries
Tubular reabsorption
Process of urine formation during which Movement of certain substances (such as toxins, ions, etc.) OUT OF/FROM peritubular capillaries INTO
renal tubules to be disposed of in urine.
Tubular secretion
Which process increases levels of something in the blood and bodily fluids, reabsorption or secretion?
Reabsorption
The process that moves solutes and water out of the filtrate and back into your bloodstream
Tubular reabsorption
tubular ___________ involves the removal of some solutes and water from the tubular fluid and their return to the blood
reabsorption
tubular ________ involves the removal of hydrogen, creatinine, and drugs from the blood and return to the
Secretion
If something is reabsorbed in the nephrons, what effect does this have on levels of it in the urine?
Decreased levels in the urine
If something is secreted in the nephrons, what effect does this have on levels of it in the urine?
Increased levels in the urine
What is GFR?
Glomerular filtration rate; a test used to check how well the kidneys are working. Represents the flow of plasma from the glomerulus into Bowman’s capsule over a specified period of time.
________ keeps GFR constant
Autoregulation
How does autoregulation keep GFR relatively constant?
Increases in systemic blood pressure cause vasoconstriction of afferent arterioles
What are the two methods by which the body controls GFR?
Sympathetic nervous system and hormonal control via renin-angiotensin-aldosterone system
What is Tm?
Transport maximum; any given substance can only transport a specific number of molecules in a certain amount of time.
What is renal plasma threshold?
It is reached when there is more transported substance in the plasma than the active transport mechanism can handle; excess spills into forming urine.
What is glycosuria?
The presence of reducing sugars in the urine, such as glucose, galactose, etc. caused by problems using or making insulin.
What is aminoaciduria
Abnormal amount of amino acids in the urine
What is renin
An enzyme secreted and stored by the kidneys that promotes the production of angiotensin
Why is renin released?
To raise low blood pressure or low sodium levels.
What are the three main organic waste products in urine?
Urea, uric acid, and creatinine
what is diuresis
Increased production of urine
What is diuretic
Causing increased passing of urine
What is hematuria
Presence of blood in urine
What is pyuria
Presence of pus in urine from bacterial infection
______ causes sodium and potassium to be excreted into the lumen.
Aldosterone
