Study Guide N ( test 3)

The functional filtration unit of the kidney is the

nephron

What is the correct branching sequence of arteries in the kidney?

renal artery → segmental arteries → interlobar arteries

The junction of the renal medulla and renal cortex is called the

corticomedullary junction

The major calyces merge to form a single, funnel-shaped

renal pelvis

Blood vessels, nerves, and the renal pelvis enter/exit the kidney at the

hilum

The main functions of the urinary system are

removal of waste and regulation of H2O and electrolyte balance

Blood vessels and the renal calyces are located in the

renal sinus

T or F

The renal cortex is more superficial than the renal medulla.

true

T or F

Urine is propelled along the ureters by peristaltic waves of muscular contractions.

true

What is the collective name for the layers of muscle in the wall of the urinary bladder?

the detrusor muscle

Reservoir for urine until micturition (urination) occurs  ________________

urinary bladder

Transports urine from kidney to urinary bladder via peristalsis  ___________________

ureter

Transports urine from urinary bladder to outside the body __________________

urethra

Filters blood and processes filtrate into tubular fluid, then urine __________________

kidney

T or F

One of the kidneys' functions is the regulation of the body's acid-base balance.

true

label the structures of the kidney

a) renal cortex

b) renal medulla

c) renal column

d) renal pyramid

e) renal papilla

f) renal pelvis

label urinary system

a) 12th rib

b) left kidney

c) right kidney

d) ureter

e) urinary bladder

f) urethra

An obstruction in the ________________ would prevent urine from leaving the kidney.

renal pelvis

Urine directly exits the body via the

urethra

The ____________ receives urine from the renal pyramid

minor calyx

The portion of the kidney in direct contact with the renal capsule is the _________________

renal cortex

The ureter and the renal artery and vein enter the kidney through the opening known as the ______

hilum

a) kidneys

b) renal artery

c) renal vein

d) inferior vena cava

e) descending abdominal aorta

f) ureters

g) urinary bladder

h) urethra

Which of the following is true concerning the location of the kidneys?

they are located behind the parietal peritoneum

What are the surround tissues of the kidney starting from the innermost to outtermost

1. fibrous capsule

2. perinephric fat

3. renal fascia

4. paranephric fat

T or F

Each kidney typically has eight to fifteen major calyces and two to three minor calyces.

false

The wide base of a renal pyramid lies next to

the renal cortex

Urine from the _________ is collected by the _________ and then drained into the _________.

renal pyramids → minor calyces → major calyces

The two components of a nephron are the

renal corpuscle and renal tubule

T or F

Filtration occurs in the renal corpuscle.

true

What is the correct sequence for parts of the renal tubule?

proximal convoluted tubule → nephron loop → distal convoluted tubule

Cortical nephrons can be distinguished from juxtamedullary nephrons by

their location within the renal cortex

The juxtaglomerular apparatus monitors?

blood Na concentration and adjusts glomerular filtration volume

label the structures of a nephron

a) cortex

b) medulla

c) distal convoluted tubule

d) glomerulus

e) proximal convoluted tubule

f) descending limb

g) ascending limb

h) collecting duct

What part of the nephron:

Contains podocytes with pedicels and filtration slits?

glomerulus

What part of the nephron:

Last part of renal tubule; drains into collecting duct

distal convoluted tubule

What part of the nephron:

Contains a descending limb and an ascending limb

nephron loop

What part of the nephron:

First part of renal tubule; cell contain microvilli

proximal convoluted tubule

label renal corpuscle

a) efferent arteriole

b) afferent arteriole

c) parietal layer of glomerular capsule

d) visceral layer of glomerular capsule

e) PCT

f) glomerulus

A renal corpuscle includes the

glomerulus and glomerular capsule

What are characteristics associated with the 2 types of nephrons?

Cortical nephrons → make up about 85% of all nephrons

Juxtamedullary nephrons → make about 15% of nephrons

T or F

The juxtaglomerular apparatus is a structure of the nephron where the DCT contacts the afferent arteriole.

true

What are the primary components of the Juxtaglomerular apparatus?

macula densa

granular cells

T or F

Macula densa cells are modified smooth muscle cells of the afferent arteriole.

false

What are the actions of granular cells in the nephron?

synthesize, store, release renin

contraction when stimulated either by stretch or by sympathetic division

What are the functions of the macula densa?

detect changes in the sodium/chloride concentration within the DCT

signaling granular cells to release renin

Blood enter the glomerulus by an ______________ arteriole

afferent

What percentage of glomerular filtrate becomes urine?

1%

Most of the water in tubular fluid is reabsorbed in the

proximal convoluted tubule

Tubular secretion involves the movement of substances

from capillary blood to tubular fluid

The first capillary bed associated with the nephron

filters blood

Which of the following correctly lists the order of structures through which urine flows after its formation in the nephron?

calyx → renal pelvis → ureter → urinary bladder → urethra

In the kidneys, blood goes from the afferent arterioles to the _________, and then enters the _________, which then delivers the blood to the _________.

glomeruli

efferent arteriole

peritibular capillaries

What is the order of vein size that blood leaves the kidney from smallest → largest?

1. cortical radiate veins

2. arcuate veins

3. interlobar veins

4. renal veins

When blood flows through the glomerulus, both water and solutes are filtered from the blood plasma, moving across the wall of the glomerular capillaries and into the capsular space to form _________.

filtrate

Fluid found after leaving the collecting ducts

urine

Fluid found in the proximal convoluted tubule (PCT)

tubular fluid

Water and solutes filtered across the glomerular capillaries

filtrate

Tubular secretion occurs when

waste products from blood pass from the peritubular capillaries to the nephron tubules.

Filtration occurs when

filtered fluid leaves the glomerulus and enters the glomerular capsule.

Tubular reabsorption occurs when

filtered fluid passes from the nephron tubules to the peritubular capillaries.

What would “increase filtration”?

increase in BP

constriction of the efferent arteriole

What would “decrease filtration”?

obstruction in the proximal tubule

increase in plasma protein concentration

increase in capsular pressure

What “Will pass through” filtration of membrane?

glucose, Na, H2O, TH, Urea

What “Will NOT pass through” filtration of membrane?

platelets, TH bound to plasma protein, RBC, Albumin, Lymphocytes

What are the renal processes that form urine?

tubular secretion

tubular reabsorption

filtration

What are the pressures that oppose glomerular hydrostatic pressure to help determine net filtration pressure?  

Blood colloid osmotic pressure

capsular hydrostatic pressure

An increased HPg causes what effects on the NFP, GFR, and reabsorption in the nephron?

NFP increases

filtrate reabsorption decreases

GFR increases

T or F

The myogenic mechanism of renal autoregulation involves the juxtaglomerular apparatus and regulation of NaCl.

false

Sympathetic stimulation results in what effects in the kidney?

decrease in GFR

vasoconstriction of the afferent arteriole

decrease in urine production

What are the organs of the urinary system?

kidneys, ureter, urinary bladder

What is the function of the kidney?

filter blood and convert the filtrate into urine

What is the function of the Ureter

transports liquid waste from the kidneys to the urinary bladder

What is the function of the Urinary bladder?

expandable, muscular sac that stores urine until it is eliminated from the body through the urethra

Describe the physiological processes that occur when the kidneys convert filtrate into urine.

Elimination of metabolic wastes: The kidneys remove waste that is present in the filtrate (e.g., urea, uric acids) to prevent these substances from reaching toxic levels within the blood.

- Regulation of ion levels: The kidneys help control the blood's ion balance, such as sodium ions (Na+) , potassium ions (K+ ) calcium ions (Ca2+ ) , and phosphate ions (PO43-) by eliminating varying amounts of these substances in the urine, depending upon dietary intake.

- Regulation of acid-base balance: The kidneys also help regulate blood pressure by excreting fluid in the urine. Regulating fluid lost in the urine helps to regulate blood volume. The kidneys also release the enzyme renin, which is required for production of angiotensin II, a hormone that increases blood pressure. Arguably, blood pressure regulation is one of the kidney's most important functions.

- Elimination of biologically active molecules: Loss of small molecules that are biologically active (e.g., hormones, drugs) also occurs as these substances are filtered, but are not reclaimed, and then become part of urine.

What are some other functions of the kidneys?

- Formation of calcitriol
- Production and release of erythropoietin
- Potential to engage in gluconeogenesis

What is the hilum?

A concave medial border where vessels, nerves, and the ureter connect to the kidney.

Describe the shape and location of the kidneys.

Kidneys are located along the posterior abdominal wall, lateral to the vertebral column. The left kidney is between the level of the T12 and L 3 vertebrae, and the right kidney is about 2 centimeters inferior to the left kidney to accommodate the large size of the liver. Both kidneys are only partially protected by the rib cage, making them vulnerable to forceful blows to the inferior region of the back.

 Why are the kidneys said to be retroperitoneal?

Because they are posterior to the parietal peritoneum

Describe the fibrous capsule

is directly adhered to the external surface of the kidney. It is composed of dense irregular connective tissue and maintains the kidney's shape, protects it from trauma, and helps prevent infectious pathogens from penetrating the kidney.

Describe the adipose capsule

is external to the fibrous capsule and A contains adipose connective tissue. It provides cushioning and stabilization for the kidney.

Describe the renal fascia

is external to the perinephric fat and is composed of dense irregular connective tissue. It anchors the kidney to surrounding structures.

label the image

a) renal cortex

b) renal medulla

c) renal column

d) renal pyramid

e) corticomedullary junction

f) renal papilla

g) renal lobe

h) renal sinus

• minor

• major

• pelvis

The kidney is innervated by which divisions of the autonomic nervous system?

Both divisions of the autonomic nervous system.

What is the functional unit of the kidney?

nephron

What are the two regions of the nephron?

renal corpuscle and renal tubule

What two structures compose the renal corpuscle?

The glomerulus and the glomerular capsule

Describe the glomerulus and the arterioles that serve and drain it.

Glomerulus: thick tangle of capillary loops called the glomerular capillaries
Blood enters the glomerulus by an afferent arteriole and exits by an efferent arteriole.

Describe the layers of the glomerular capsule. 

Two layers:
Visceral layer: internal, permeable; directly overlies the glomerular capillaries
Parietal layer: external, impermeable; composed of simple squamous epithelium

Where is the capsular space located?

located between the visceral and parietal layer

What is the first region of the renal tubule? 

What epithelium composes it? 

What feature helps increase its reabsorption capacity?

1. Proximal convoluted tubule (PCT)

2. Composed of simple cuboidal epithelium

3. Apical microvilli that markedly increase its surface area and this its reabsorption capacity.

What are the two limbs of the nephron loop? 

What composes the thick segments? 

Thin segments?

Descending limb and ascending limb.
Thick: simple cuboidal epithelium
Thin: simple squamous epithelium

What is the last region of the renal tubule? 

How does its lumen appear with a light microscope? 

How does this compare to the PCT?

1. Distal convoluted tubule (DCT)

2. appears clear

3. compared to PCT DCT does not appear fuzzy

What are the two types of nephrons?

cortical nephrons and juxtamedullary nephrons

What are cortical nephrons?

are oriented with their renal corpuscles near the peripheral edge of the cortex and have a relatively short nephron loop that barely penetrates the medulla. Thus, the bulk of a cortical nephron resides within the cortex. Approximately 85% of nephrons are cortical nephrons.

What are juxtamedullary nephrons?

Their renal corpuscles lie adjacent to the corticomedullary junction, and they have relatively long nephron loops that extend deep into the medulla. Juxtamedullary nephrons are important in establishing a salt concentration gradient within the interstitial space that lies outside the nephron loop, the collecting tubules, and the collecting ducts thus allowing for the regulation of urine concentration by antidiuretic hormone (ADH).

What do nephrons drain into?  (These in turn drain into larger structures.)  See figure 2.9.

collecting tubules (these drain into collecting ducts)

The _____________ convoluted tubule contacts the _________ arteriole of the same nephron

(note that many of the nephron illustrations do not show this. 

The __________________________ apparatus is a structure at this junction.

distal

afferent

juxtaglomerular (JG)

What are the components of the JG apparatus?

Granular cells and macula densa cells

What are granular cells? 

Where are they located? 

modified smooth muscle cells of the afferent arteriole

located near its entrance into the renal corpuscle.