CH 19 - The Kidneys (EXAM 4)

Six basic functions of the kidney:

1. Regulation of _____ ____volume and blood _____

2. Regulation of ____

3. Maintenance of ____ balance

4. Homeostatic regulation of ___

5. Excretion of ____

6. Production of ____

extracellular fluid, pressure, osmolarity, ion, pH, wastes, hormones

4 parts of the urinary system

kidneys, ureters, urinary bladder, urethra

Part of the urinary system that filters blood plasma + makes urine by removing waste products

kidneys

Kidneys ____ blood plasma and make ____ by removing ___ products

filter, urine, waste

How many kidneys do most people have?

2

Name the two kidneys most people have

right, left

Someone may have three kidneys if they’ve received a ____ kidney

donation

Part of the urinary system that carry urine from the kidneys to the bladder

ureters

Two types of ureters

right, left

Right and left ureters carry ____ from the right and left ____ to the ____

urine, kidneys, bladder

Ureters work in _____- _____

• They ensure urine moves in ____ direction towards the ____

anti-gravity, one, bladder

Part of the urinary system that stores urine

urinary bladder

T/F: The urinary bladder and gallbladder are the same thing

F

The urinary bladder ____ urine

stores

Part of the urinary system that carries urine from the bladder to the external environment

urethra

The urethra carries urine from the ____ to ____ _____

bladder, external environment

Path of urine flow through the urinary system (4 parts):

Kidneys → Ureters → Urinary bladder → Urethra

Kidneys require ____ (low/ high) blood flow in order to ____ the blood plasma

high, filter

Vascular elements of the kidneys (supplies blood):

renal arteries + veins

How much of resting blood flow goes to the kidneys?

• 10 - 15%

• 20 - 25%

• 30 - 35%

• 45 - 50%

20 - 25%

The renal portal system consists of two _____ ____ in a row:

1. _____

2. ____ _____

capillary beds, glomerulus, peritubular capillaries

Consists of two capillary beds in a row (glomerulus and the peritubular capillaries)

renal portal system

Capillary beds in series in the renal portal system (in order)

glomerulus, peritubular capillaries

Capillary bed in the renal portal system that receives blood from the afferent arteriole

glomerulus

Capillary bed in the renal portal system that receives blood from the efferent arteriole

peritubular capillaries

The glomerulus in the renal portal system is a capillary bed that receives blood from the ____ arteriole

afferent

Peritubular capillaries in the renal portal system are capillary beds that receive blood from the ____ arteriole

efferent

The peritubular capillaries are also called ___ _____

vasa recta

Functional unit of the kidney

nephron

Acts as the kidney’s filter

nephron

Nephrons act as the kidney’s ____

filter

Nephrons are located in two regions: _____ (OUTER layer) and ____ (INNER layer)

cortex, medulla

The cortex is the ____ layer of nephrons and contains ____% ____ nephrons

outer, 80, cortical

The medulla is the ____ layer of nephrons and contains ____% ____ nephrons

inner, 20, juxtamedullary

Renal corpuscle of each nephron is made of what two things?

Bowman’s capsule, glomerulus

In the renal corpuscle of the nephron, ______ blood vessel walls overlap _____ ____ to allow for ____ to occur

glomerulus, Bowman’s capsule, filtration

Flow of filtrate through each nephron (4 steps)

proximal tubule → loop of Henle → distal tubule → collecting ducts

Loop of Henle in the nephron is made of two parts:

• ______ + _____ ____

descending + ascending limb

Collecting ducts in a nephron converge and drain into the ___ ___ (final ___ collection)

renal pelvis, urine

Common collecting duct for all of the individual collecting ducts (collecting duct for collecting ducts)

renal pelvis

Refers to the movement of substances from blood into the nephron lumen of the kidney

kidney filtration

The nephron lumen can be described as a ___ tube

hollow

Kidney filtration refers to the movement of substances from ____ into _____ ____

blood, nephron lumen

Site of kidney filtration

renal corpuscle

The renal corpuscle is the site of ___ ____

kidney filtration

Three filtration barriers in the kidney

• ___ ____ endothelium

• ____ _____

• _____ of ____ _____

glomerular capillary, basement membrane, epithelium of Bowman’s capsule

The glomerular capillary endothelium, one of the three filtration barriers, is ____ (contains ____)

• This allows most ____ components to enter the ____ of the nephron

• Blocks blood ___ and ____

fenestrated, pores, plasma, lumen, cells, solids

The basement membrane, one of the three filtration barriers of the kidney, is an ____ coarse sieve

• Filters out ____ ___ (ex. glycoproteins)

acellular, plasma proteins

The epithelium of Bowman’s capsule, one of the three filtration barriers, contains ____ with foot processes

• Forms ____ filtration slits

• Slit ____ can change based on need

podocytes, adjustable, size

Three pressure influences in the kidney

• ______ _____ pressure

• _____ _____ ____ pressure

• ____ ____ pressure

capillary blood, capillary colloid osmotic, capsule fluid

Capillary blood pressure:

• _____ pressure

• +____ mmHg

• ____ (opposes/ favors) filtration

• Moves things from ____ into ____

hydrostatic, 55, favors, blood, kidney

Capillary colloid osmotic pressure:

• Creates/ driven by ___ ____ concentration

• +_____ mmHg

• _____ (opposes/ favors) filtration (moves things from ____ into ___)

plasma protein, 30, opposes, kidney, blood

Capsule fluid pressure

• ____ pressure inside ____ ____

• +_____ mmHg

• ____ (opposes/ favors) filtration

hydrostatic, Bowman’s capsule, 15, opposes

net filtration pressure equation

NFP = capillary pressure - (colloid osmotic pressure + capsule pressure)

Which pressure influences favor filtration?

capillary pressure

Which pressure influences opposes filtration?

colloid osmotic pressure, capsule pressure

Volume of blood filtered by glomeruli per unit time

glomerular filtration rate

Glomerular filtration rate is a key indicator of ____ _____

kidney function

Determinants of glomerular filtration rate (2)

net filtration pressure, filtration coefficient

Net filtration pressure depends on ___ blood ____ and blood ____

renal, flow, pressure

Filtration coefficient depends on:

• ____ ____ of glomerular capillaries that are available for filtration

• _____ of filtration slits

surface area, permeability

Autoregulation of GFR is driven by 3 things:

• ____ ___ response

• ____ ____

• ___ + ____ nervous system

myogenic autoregulation, juxtaglomerular apparatus, hormones, autonomic

In the myogenic autoregulation response, vascular ____ muscle ____ secondary (in response) to stretch

smooth, contracts

In the myogenic autoregulation response, ____ pressure → vaso____ → protects _____

increased, constriction, glomeruli

The myogenic autoregulation response is important because it prevents ___ from high ___ ____

• Prevents ___ because it ____ things down

damage, blood pressure, bursting, slows

2 main cell types of the juxtaglomerular apparatus

macula densa cells, granular cells

Macula densa cells in the juxtaglomerular apparatus:

• Detect ___ in filtrate

• High NaCl occurs due to increased ____

• When macula densa cells sense more ____ in filtrate → send signals to help increase the ____ + ____ down GFR

NaCl, GFR, NaCl, resistance, slow

Granular cells in the juxtaglomerular apparatus:

• Secrete ___ (regulates Na+/ ____ balance)

renin, water

Hormone that decreases/ slows GFR through vasoconstriction

angiotensin II

Hormone that increases/ speeds up GFR through vasodilation

prostaglandins

Kidneys maintain stable ____ despite blood pressure changes

• Dual regulation (___ and ____ ____) provides precise control

• ____ fine-tune filtration based on body needs

GFR, myogenic, juxtaglomerular apparatus, hormones

Angiotensin II is a hormone that ____ (decreases/ increases) GFR through vaso_____

decreases, constriction

Prostaglandins are hormones that ____ (decreases/ increases) GFR through vaso_____

increases, dilation

Brings blood to the glomerulus in the kidneys

afferent arteriole

Carries blood away from the glomerulus in the kidneys

efferent arteriole

INCREASE in resistance in afferent arteriole = vaso____ = ____ (decreased/ increased) blood flow into glomerulus = ____ (decreased/ increased) GFR

• ____ (less/ more) filtration

constriction, decreased, decreased, less

DECREASE in resistance in afferent arteriole = vaso____ = ____ (decreased/ increased) blood flow into glomerulus = ____ (decreased/ increased) GFR

• ____ (less/ more) filtration

dilation, increased, increased, more

INCREASE in resistance in efferent arteriole = vaso____ = blood ___ (leaves/ stays in) glomerulus ____ (longer/ faster)

• _____ (decreased/ increased) GFR b/c ___ (less/ more) time for filtration

constriction, stays in, longer, increased, more

DECREASE in resistance in efferent arteriole = vaso____ = blood ___ (leaves/ stays in) glomerulus ____ (longer/ faster)

• _____ (decreased/ increased) GFR b/c ___ (less/ more) time for filtration

dilation, leaves, faster, decreased, less

GFR depends on ___ ___ across glomerulus

pressure gradient

____ arteriole controls blood flow IN

afferent

____ arteriole controls blood retention time

efferent

Refers to the process of moving filtrate back into the blood

reabsorption

Reabsorption is the process of moving ___ back into the ___

filtrate, blood

Reabsorption occurs in the ____ ____ in the ____ ____

proximal tubule, peritubular capillaries

Primary mechanism of reabsorption (3 words)

active sodium transport

_____ ____ _____ drives reabsorption b/c ___ follows salt (____)

• Reabsorbs/ brings things back into the ____ along with the watery ___

active sodium transport, water, osmosis, blood, filtrate

Type of secondary active transport when two molecules move across a cell membrane in the same direction

• Facilitated by a membrane protein

symport

Symport is a type of ____ active transport when two molecules move across a cell membrane in the ___ direction

• Facilitated by a membrane protein called a _____

secondary, same, symporter

Through secondary active transport, ____, ____ ____, and other organic molecules are reabsorbed

• Moves things back into the ____ attached to ___, which the body needs to retain

glucose, amino acids, blood, sodium

Through passive reabsorption, ___ is passively reabsorbed by ___ back into the ____

• Driven by the presence/ absence of a ____

urea, diffusion, blood, gradient

Urea is ____ reabsorbed by diffusion back into the blood

passively

Plasma proteins ____ (are/ are not) something we want to retain in the body, so they are ____, broken down into ___ ____, and returned to the blood for ____

are, endocytosed, amino acids, reuse

Maximum rate at which substances can be reabsorbed before the system is saturated + forced to excrete the excess

transport maximum

Transport maximum is the maximum rate at which substances can be ___ before the system is ___ and forced to ___ the excess

reabsorbed, saturated, excrete

Transport maximum is shown through diabetes mellitus where excess ___ is excreted through the ____

glucose, urine

Process that occurs after reabsorption that involves the selective transfer of substances from blood into tubule lumen

secretion

Secretion occurs ____ (before/ after) reabsorption

after

Secretion refers to the selective transfer of substances from ___ into ___ ____

• Fine-tunes ____ composition

blood, tubule lumen, filtrate

Secretion is ____ (less/ more) selective than filtration

more