***FINAL EXAM: Chapter 26 The Urinary System単語カード | Quizlet

urinary system

kidneys, ureters, urinary bladder, urethra

cleanse the blood of nitrogenous wastes, toxins, excess ions and water, and other unnecessary or undesirable substances by forming urine

maintain proper chemical composition of the blood and other body fluids (regulate blood volume)

functions of kidneys

urea, uric acid, creatinine

What are nitrogenous compounds (main waste products) excreted in urine?

urea

waste derived from breakdown of amino acids during normal recycling of body's proteins

uric acid

waste from turnover of nucleic acids

creatinine

waste formed by the breakdown of creatine phosphate, a molecule in muscle that stores energy for ATP production

ureters

The tubes that carry urine from the kidneys to the bladder.

urinary bladder

temporary storage reservoir for urine

urethra

tube that carries urine to body exterior

superior lumbar region of the posterior abdominal wall

Where do the kidneys lie?

right kidney

which kidney is crowded by the liver and lies slightly inferior compared to the other kidney?

renal hilum

A medial indentation where several structures enter or exit the kidney (ureters, renal blood vessels, and nerves)

renal capsule, adipose capsule, renal fascia

What are the layers that surround each kidney from deep to superficial?

renal capsule

fibrous capsule made up of dense connective tissue layer of collagen fibers, adheres to kidney's surface

maintains the shape of the kidney

forms a barrier to inhibit the spread of infection

provides mechanical protection

adipose capsule

also known as perirenal fat

layer of fat around the kidney - provides cushion

renal fascia

dense outer layer formed by collagen fibers that extend outward from the inner renal (fibrous) capsule through the adipose capsule

anchors the kidney to surrounding structures

posteriorly - bound to deep fascia surrounding the muscles of body wall

anteriorly - it is attached to the peritoneum and to the anterior renal fascia of the opposite end

pararenal fat

outermost layer between renal fascia and peritoneum

separates the posterior and lateral portions of the renal fasica from the body wall

renal cortex and renal medulla

What are the two distinct regions of kidney tissue?

renal cortex

the granular and reddish-brown outer layer of the kidney, which is in contact with the renal (or fibrous) capsule

renal columns

Inward extensions of the cortex tissue separating the renal pyramids

renal medulla

darker regions located internal to the renal cortex

consists:

medullary pyramids

renal papillae

renal lobe

renal sinus

large space within the medial part of the kidney opening to the exterior through the renal hilus

renal pelvis

flat, funnel-shaped tube

expanded superior part of the ureter, which has branching extensions of 2-3 major calices

major calices

further branch out as minor calices

minor calices

smaller cup-shaped tubes that enclose the papillae of the pyramids

collect urine draining from the papillae and empty it into the renal pelvis, then into the ureters, and finally into the urinary bladder

function of the calices

Renal A

Segmental A

Lobar A

Interlobar A

Arcuate A

Interlobular A

Afferent Arterioles

Glomerulus

Efferent Arterioles

Peritubular Capillaries/Vasa Recta

Interlobular V

Arcuate V

Interlobar V

Renal V

Inferior Vena Cava

What is the blood flow in the kidneys?

uniferous tubule

the main structural and functional unit of the kidney

nephron

basic functional unit of the kidney

nephron

urine-forming structure

components:

renal corpuscle

proximal convoluted tubule

loop of Henle

distal convoluted tuble

collecting tubule (duct)

concentrates urine by removing water from the urine formed in the nephron

lined by simple epithelium throughout its length

filtration, reabsorption, secretion

What are the 3 mechanisms of urine production?

filtration

filtrate of blood leaves the kidney capillaries and enters the nephron

reabsorption

passive process - most nutrients, water and essential ions are reclaimed from the fitrate and returned to the blood of capillaries

secretion

active process - moves additional undesirable molecules into the collecting tubule from the blood of surrounding capillaries

glomerulus

A ball of capillaries surrounded by Bowman's capsule in the nephron and serving as the site of filtration in the vertebrate kidney.

glomerular capsule

enclosing structure surrounding each glomerulus

afferent and efferent arterioles

The glomerular capillaries are connected to the bloodstream via what two arterioles?

parietal layer

visceral layer (with podocytes and pedicels - foot processes surrounding the glomerular capillaries)

What are the 2 layers of the glomerular capsule?

filtration slits (thin clefts between the pedicels)

filtrate passes into the capsular space through what?

glomerular capillaries

produces FILTRATE that moves through the rest of the uriniferous tubules, forming urine.

filtration membrane or apparatus (barrier)

actual filter that lies between the blood in the glomerulus and the capsular space

1. fenestrated edothelium

2. filtration slits

3. intervening basement membrane

The filtration membrane or apparatus has 3 layers of physical barriers:

mesangial cells

What type of cell is involved with the filtration membrane and functions in:

providing physical support for capillaries

engulf organic materials

regulate the diameters of the glomerular capillaries

proximal convoluted tubule

nephron component that is confined entirely to the renal cortex

- most active in REABSORPTION and SECRETION

- contains increased number of mitochondria

Loop of Henle (nephron loop)

has a descending limb and an ascending loop part of the nephron

thick segment of ascending loop

Loop of Henle

this segment begins in the medulla and contains active transport mechanisms that pump sodium and chloride ions out of the tubular fluid

thin segment of ascending limb

Loop of Henle

this segment is freely permeable to water, but relatively impermeable to ions and other solutes

distal convoluted tubule

confined to the renal cortex

specialized for selective secretion and reabsorption of ions

functions in conserving body fluids

corticol nephrons (85% of all nephrons)

juxtamedullary nephrons (15% of all nephrons)

Classes of nephrons divided according to location

collecting tubules (collecting ducts)

receive urine from distal convoluted tubules

run straight through the cortex into the deep medulla

main function: conserve body fluids

Papillary Ducts (Ducts of Bellini)

The medullary collecting ducts travel to the apex of the pyramid where they merge into larger collecting ducts called ________ that open into the minor calyx.

ADH (antidiuretic hormone)

During water conservation, what hormone is secreted by the posterior pituitary gland and increases permeability of the collecting tubules and DCT to water.

glomerulus: high resistance vessels

peritubular capillaries: drains the cortical glomerulus, low pressure

vasta recta: run alongside loops of henle in deepest part of renal cortex (role: kidney's urine-concentrating mechanism)

Difference between blood vessels associated with the uriniferous tubules:

Glomerulus VS. Peritubular capillaries VS.

vasa recta

the ureters

enters the bladder posteriorly

slender tubes that carry urine from the kidneys to the bladder; continuation of the renal pelvis

mucosa, muscularis, adventitia

What are the 3 basic layers of the ureter walls?

deep to superficial

peristaltic waves

propels urine to bladder

urinary bladder

collaspsible, muscular sac that temporarily stores and expels urine

lies anterior to rectum in males; lies anterior to vagina and inferior to uterus in females

rugae

folds in the mucosal lining disappear as the bladder stretches and fills with urine

posterolateral angles (ureteral openings)

urachus

inferior angle (neck)

trigone

Features of the urinary bladder

trigone

triangular region of the posterior wall of the bladder interior defined by openings for both ureters and the urethra

lacks rugae

smooth and very thick in appearance

acts as a funnel

mucosa, muscularis, fibrous adventitia

What are the 3 layers of the urinary bladder wall from deep to superficial?

detrusor muscle

contraction of this muscle compresses the urinary bladder and expels its contents into the urethra

What kind of muscle is in the muscularis layer of the bladder wall?

prostatic urethra, membranous urethra, spongy urethra

The male urethra is divided into 3 portions.

internal urethral sphincter

thickening of detrusor muscle

INVOLUNTARY sphincter of SMOOTH muscle that keeps the urethra closed when urine is not being passed & prevents dribbling of urine between voidings/urination

external urethral sphincter

surrounds urethra within the sheet of muscle called urogenital diaphragm; SKELETAL muscle

VOLUNTARY sphincter to inhibit urination until proper time

micturition

act of passing urine brought by the contraction of detrusor muscle, assisted by muscles of the abdominal wall, which contract to increase the intra-abdominal pressure

Glomerular (Bowman's) capsule

Proximal convoluted tubule

Loop of Henle

Distal convoluted tubule

Collecting tubule/duct

Papillary duct

Minor calyx

Major calyx

Renal pelvis

Ureter

Urinary Bladder

Urethra

Urine flows through the renal tubule of the kidney in what order?