A&P II Chapter 24: Urinary system

True or false: The main function of the urinary system is to remove oxygen from the bloodstream.

False

The kidneys aid in acid-base balance by altering the rate of reabsorption of which of the following?

Bicarbonate

Hydrogen

The kidneys are located along the ______ abdominal wall.

Posterior

The kidneys are retroperitoneal. Which description below describes what this means?

The kidneys are posterior to the peritoneum.

Besides removing waste products from the bloodstream, the urinary system performs many other functions, including which of the following?

erythropoietin production

acid-base balance

urine storage

When a kidney is sectioned along a coronal plane, there is an outer renal ______ and an inner renal ______.

Cortex

Medulla

The kidneys help control the blood's inorganic ion balance. Which of the following ions are controlled primarily by the kidneys?

calcium

potassium

phosphate

sodium

The renal ______ tends to be a darker shade than the renal ______.

medulla; cortex

Kidneys are ______ protected by the rib cage.

Partially

The anterior surface of the kidneys is covered with ______ and the posterior surface lies directly against the posterior abdominal wall.

peritoneum

The innermost portion of a kidney is called the ______.

medulla

The wide base of a renal pyramid lies next to the ______.

Cortex

Extensions of the cortex, called renal ________, project into the medulla and subdivide the medulla into renal ________.

columns

pyramids

True or false: A human kidney is divided into 20 renal lobes.

False

The apex of the renal pyramid is called the renal _______ and it projects toward the renal sinus.

Papilla

The major calyces merge to form a large funnel-shaped renal ______.

Pelvis

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

renal pyramids; minor calyces; major calyces

The renal tubule consists of which of the following?

proximal convoluted tubule

nephron loop

distal convoluted tubule

The ______ is lined by simple cuboidal epithelium with tall microvilli for maximum reabsorption.

proximal convoluted tubule

The ascending limb of the nephron loop returns to the renal cortex and terminates at the __________ __________ tubule.

Distal

Convoluted

The glomerular capsule has two layers. One layer, the ______ layer, lies directly over the glomerulus.

visceral

The thin segment of the descending limb of the nephron loop is lined with _______ _______ epithelium.

Simple Squamous

Several ______ calyces merge to form larger spaces called ______ calyces.

Minor

Major

The nephron loop originates in the ______ and descends down into the ______ and then ascends back into the ______.

cortex; medulla; cortex

There are two types of nephrons, cortical nephrons, and __________ nephrons.

Juxtamedullary

The ________ nephrons make up approximately 85% of the nephrons in a human kidney.

Cortical

The thin part of the ascending limb of the nephron loop is lined with simple ___________ epithelium and the thick part, is lined with simple cuboidal epithelium

squamous

Which type of nephron has a renal corpuscle that lies close to the corticomedullary junction with a long nephron loop that extends deep into the medulla?

Juxtamedullary

The first part of the descending limb of the nephron loop, also known as the thick descending limb, is lined with epithelium.

Simple Cuboidal

Which type of nephron plays the more important role in establishing a salt concentration gradient?

juxtamedullary

When the tubular fluid leaves the distal convoluted tubules, it must travel through a series of small ______ that empty into ______.

collecting tubules; collecting ducts

Which type of nephron has relatively short nephron loops that barely extend into the medulla?

Cortical

Which tubules stain more darkly and appear fuzzier in a histological preparation of the renal cortex?

proximal convoluted tubules

Only about 15% of our nephrons are nephrons.

juxtamedullary

Which are components of the juxtaglomerular apparatus?

macula densa, granular cells, and extraglomerular mesangial cells

Granular or juxtaglomerular cells are modified ________ ________ cells.

Smooth

Muscle

The cells of the macula densa are easy to recognize because they are ______ and ______ than the other cells of the DCT.

taller; narrower

Collecting tubules and collecting ducts project through the ______ toward the ______.

renal medulla; renal papilla

The macula densa cells continuously monitor ______ in the tubular fluid.

NaCl concentration

One component of the juxtaglomerular apparatus is which of the following?

granular cells

The juxtaglomerular cells are modified smooth muscle cells of the __________ arteriole located near the renal corpuscle.

afferent

At least 20- 25% of the resting ______ normally flows through the kidney via the renal artery.

cardiac output

The ___________ __________ is a group of modified epithelial cells in the distal convoluted tubule that touch the granular or juxtaglomerular cells.

Macula

Densa

The granular cells of the JGA, synthesize, store and release ______.

Renin

The segmental arteries branch to form the ______ arteries that travel through the renal columns.

Interlobar

The ______ arteries are parallel to the base of the medullary pyramid at the junction of the cortex and the medulla.

Arcuate

The fluid that is formed when blood flows through the glomerulus and some components of the plasma enter the capsular space is called _________.

Filtrate

When blood leaves the glomerulus, it enters the __________ arteriole.

Efferent

Renal arteries branch directly into ______ arteries.

Segmental

The ______ are associated with the nephron loop and primarily reside in the medulla of the kidney.

Vasa Recta

The ______ arteriole leads to the glomerulus and the ______ arteriole leads away from the glomerulus.

afferent; efferent

Blood flows from the renal artery to the ______ arteries in the area of the renal sinus.

segmental

Once the tubular fluid leaves the ______, it is called urine.

collecting duct

The arcuate arteries give off branches called ______ arteries that project peripherally into the cortex.

Interlobular

True or false: Blood components that do not exit the glomerulus as filtrate exit the renal corpuscle through an efferent arteriole.

True

Which of the following are the processes by which urine is formed?

filtration

tubular secretion

tubular reabsorption

The ______ are associated with the convoluted tubules and primarily reside in the cortex of the kidney.

peritubular capillaries

The process by which water and some dissolved solutes in the blood plasma passively move out of the glomerulus and into the capsular space of the renal corpuscle is called ___________ ____________.

filtration

Interlobular veins merge to form ______ veins.

arcuate

When substances in the filtrate move back into the blood it is called ______.

tubular reabsorption

Tubular secretion, the movement of solutes out of the blood into the tubular fluid, usually occurs by ______.

active transport

Which of the following happens first?

filtration

When the blood plasma moves out of the glomerulus and into the glomerular capsule, it is now called ______.

filtrate

Which are the most accurate descriptions of the structures that make up the filtration membrane?

glomerular endothelium

filtration slits

True or false: In tubular reabsorption, all needed solutes and most water that formed the filtrate are reabsorbed into the nephron.

False

The filtration slits between the ________permit the ready passage of filtered material into the capsule space.

Pedicels

______ is the active transport of solutes out of the blood into the tubular fluid.

Tubular secretion

Filtrate is produced due to the difference between _______ pressure of the blood in the glomerulus and the opposing pressures of the osmotic blood pressure and fluid pressure in the capsular space.

hydrostatic

The pedicels are separated by thin spaces called _________ slits, which allow materials from the plasma to pass into the capsular space.

filtration

One of the factors that cause materials to be filtered from the glomerulus is that the ______ arteriole is wider in diameter than the ______ arteriole.

afferent; efferent

The ______ is designed to be "leaky" to allow some plasma and solutes to be filtered.

glomerulus

Blood __________ __________pressure opposes filtration because it tends to pull or draw fluids into the glomerulus from the capsular space.

colloid

osmotic

Which substances are not filtered through the kidneys?

erythrocytes

leukocytes

platelets

True or false: The glomerular filtration rate is expressed as volume per unit time (usually 1 hour).

False

As the net filtration pressure decreases, the GFR __________.

Decreases

Glomerular filtration regulation involves intrinsic control which could best be described as ______.

renal autoregulation

The wider diameter of the ____________ arteriole allows the blood to enter the glomerulus under high pressure which helps filter the plasma and solutes out of the glomerulus.

Afferent

Renal _________ is the intrinsic ability of the kidney to maintain constant blood pressure.

Autoregulation

Blood colloid osmotic pressure is due to the ________ ________ it contains.

Plasma Proteins

The ______ is defined as the rate at which the volume of filtrate is formed.

glomerular filtration rate

A decrease in blood entering the afferent arteriole will result in _______.

vasodilation

As net filtration pressure increases, the GFR ______.

Increases

An increase in systemic blood pressure causes a(n) ______ in the volume of blood that enters the afferent arteriole.

increase

Glomerular filtration is influenced by changing the ______ and _______.

diameter of the afferent arteriole, surface area available in the filtration membrane

Renal autoregulation functions by two mechanisms, the ________ mechanism, and the tubuloglomerular feedback mechanism.

myogenic

True or false: The tubuloglomerular feedback mechanism acts as a 'backup' mechanism to the myogenic mechanism in response to increased systemic blood pressure.

True

Blood ________ _______- pressure opposes filtration because it tends to pull or draw fluids into the glomerulus from the capsular space.

colloid osmotic

If the MAP decreases below ______ mm Hg, no further arteriole dilation can bring a decrease in glomerular blood pressure.

80

A decrease in blood pressure, detected by the afferent arteriole, will result in vasodilation. The glomerular blood pressure and the GFR will respond by ______.

remaining normal

Sympathetic stimulation causes granular cells to release ______.

Renin

An increase in systemic BP will result in ______, which will result in the glomerular blood pressure ______.

vasoconstriction; remaining normal

The hormone ________ ________ is released from the atria in response to distension of these chambers.

Atrial Natriuretic Peptide

The tubuloglomerular feedback mechanism will respond by increasing ______ even further If the myogenic mechanism is not sufficient to maintain normal glomerular blood pressure due to increased systemic BP.

vasoconstriction

Renal autoregulation maintains GFR by altering the size of the ______ arteriole.

afferent

True or false: If systemic blood pressure is dangerously low, filtration and the elimination of wastes in urine ceases, resulting in the accumulation of toxic metabolic wastes in the blood.

True

Substances are _________ when they move from the tubular fluid back into the blood.

Reabsorbed

Sympathetic stimulation causes the release of renin which will result in the subsequent production of ______ which will result in a(n) ______ in the GFR.

angiotensin II; decrease

Atrial natriuretic peptide ______ GFR to eliminate fluid when there is a(n) ______ in blood volume and/or blood pressure.

Increases

Increase

The _______ __________ is the maximum amount of a substance that can be reabsorbed (or secreted) across the tubule epithelium in a given period of time.

Transport Maximum

Direct stimulation by the ______ nervous system decreases GFR by causing vasoconstriction of afferent arterioles.

sympathetic