Human Anatomy & Physiology



Anatomy & Physiology II Dr. L. Bacha

Chapter Outline (Marieb & Hoehn 2019)

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( indicate the numerous ways that the kidneys maintain the body’s internal environment (listed next to the blue bullets on pages 974 and 975):

( regulating the total volume of water in the body and the total concentration of solutes in that water (osmolality)

( regulating concentrations of the various ions in the extracellular fluids

( ensuring long-term acid-base balance

( excreting metabolic wastes and foreign substances such as drugs or toxins

( producing erythropoietin and renin, important molecules for regulating red blood cell production and blood pressure, respectively

( converting vitamin D to its active form

( carrying out gluconeogenesis during prolonged fasting

( along with the kidneys, the urinary system also includes what organs?

ureters, urinary bladder, urethra

25.1 The kidneys have three distinct regions and a rich blood supply

Location and External Anatomy

( describe the shape of the kidneys: bean-shaped

( they are retroperitoneal, which means they are situated between the parietal peritoneum and muscles of the back

( describe their location relative to the vertebral column and specific vertebrae:

in the superior lumbar region, extending approx. from T12 to L3

( a typical adult kidney is about the size of what everyday object?!

large bar of soap

( describe the following:

renal hilum -

the vertical cleft on the concave, medial surface

renal sinus -

the internal space, that the hilum leads into, within the kidney

( list and briefly describe the three layers of supportive tissue that surround each kidney:

1. the renal fascia, and outer layer of dense fibrous connective tissue that anchors the kidney and the adrenal gland to surrounding structures

2. the perirenal fat capsule, a fatty mass that surrounds the kidney and cushions it against blows

3. the fibrous capsule, a transparent capsule that prevents infections in surrounding regions from spreading to the kidney

Internal Gross Anatomy

Locate the following parts of the kidney in Fig. 25.4:

renal cortex -the more superficial region

renal medulla - the region deep to the cortex

- formed by about 8 cone-shaped renal pyramids

- the apex (rounded tip) of each pyramid that points internally is called the renal papilla

lobe of a kidney = one renal pyramid and its overlying cortex

renal pelvis

- describe the renal pelvis:

a funnel-shaped tube, continuous with the ureter leaving the hilum

major calyces (calyx is singular) – branching extensions of the renal pelvis; each major calyx subdivides to form several minor calyces

minor calyces – cup-shaped areas that enclose the renal papilla of each renal pyramid

- the calyces collect what? urine

- the walls of the calyces, pelvis, and ureter contain smooth muscle that does what?

contracts to rhythmically propel urine by peristalsis

Blood and Nerve Supply

( the kidneys have a rich blood supply because they continuously cleanse the blood and adjust its composition

( under normal resting conditions, the renal arteries deliver what fraction of the total cardiac output to the kidneys each minute?

one fourth of the total cardiac output (about 1200 ml)

( examine Figs. 25.5 and 25.8 and trace the blood vessels listed below:

renal artery (one branches to each kidney from the abdominal aorta)

( segmental arteries which branch into

( interlobar arteries (extend between pyramids)

( arcuate arteries (arc between the medulla and cortex)

( cortical radiate arteries (radiate up into the cortex)

( afferent arterioles

( glomerulus = a ball-like network of glomerular capillaries within the glomerular capsule

(efferent arterioles

(peritubular capillaries (network of capillaries that surround the PCTs, DCTs and part of collecting duct, which we will get to!) or vasa recta (capillary loops that surround the nephron loop and collecting ducts)

( cortical radiate veins ( arcuate veins ( interlobar veins ( renal veins ( inferior vena cava

25.2 Nephrons are the functional units of the kidney

Nephrons are the microscopic structural and functional units of the kidneys

( each kidney contains how many nephrons? about 1 million

( nephrons empty their processed filtrate into one of thousands of collecting ducts, which do what?

convey this fluid, now called urine, into the renal pelvis

( each nephron consists of what two parts?

the renal corpuscle and the renal tubule

Renal Corpuscle

A renal corpuscle is formed of two parts: a glomerulus and glomerular capsule

Glomerulus = a ball-like tuft of capillaries, called glomerular capillaries

Glomerular Capsule (Bowman’s capsule)- a cup shaped, hollow structure; it almost completely surrounds the glomerulus and is continuous with the renal tubule

The glomerular capsule consists of three parts:

⦁. parietal layer of the glomerular capsule - simple squamous epithelium and comprises the outer wall of the capsule

⦁ visceral layer of the glomerular capsule - formed by unique, modified epithelial cells called podocytes (we’ll get back to these!) that cling to the glomerular capillaries

⦁ the capsular space - the space between the two epithelial layers into which fluid filtered from the glomerular capillaries enters

◦ the renal corpuscle is where blood is filtered during a process called glomerular filtration to form fluid called glomerular filtrate

◦ examine the renal corpuscles in Fig. 25.6 to 25.10

Renal Tubule and Collecting Duct

RENAL TUBULE

◦ the renal tubule is the tubular portion of a nephron into which filtrate passes from the capsular space of the glomerular capsule

◦ reabsorption and secretion occur here

◦ examine the parts of the renal tubule in Fig. 25.6

◦ parts of the renal tubule:

Proximal convoluted tubule (PCT)

Nephron Loop (loop of Henle)

⦁ thick descending limb

⦁ thin segment

⦁ thick ascending limb

Distal convoluted tubule (DCT)

DCTs from several nephrons empty into a collecting duct

COLLECTING DUCT

- the distal convoluted tubules of many nephrons open into one collecting duct

- many collecting ducts open at the renal papilla

Classes of Nephrons

Name the two groups of nephrons and note each type in Fig. 25.8:

cortical nephrons and juxtaglomerular nephrons

Nephron Capillary Beds

The renal tubule of every nephron is closely associated with how many capillary beds?

two

Glomerulus

( the capillaries of the glomerulus are specialized for what? filtration

( how does it differ from all other capillary beds in the body?

it is both fed and drained by arterioles

- name the arterioles:

afferent arteriole and efferent arteriole

( this arrangement maintains what?

the high pressure in the glomerulus that is needed for filtration

( the afferent arterioles arise from what vessels that run through the cortex?

cortical radiate arteries

( the efferent arterioles feed into what?

either the peritubular capillaries or vasa recta

Peritubular capillaries

( peritubular capillaries arise from the efferent arterioles and cling closely to the PCTs, DCTs, and parts of collecting ducts in the cortex of the kidney

( because they arise from efferent arterioles, which have high resistance, they are low pressure vessels

- as a result, these low-pressure, porous capillaries readily do what?

absorb solutes and water from the tubule cells as these substances are reclaimed from the filtrate

Vasa recta

- vasa recta are bundles of long straight capillaries that surround the nephron loops (loops of Henle) and the collecting ducts in the medulla of the kidney

25.3 Overview: Filtration, absorption, and secretion are the key processes of urine formation

( List and read about the three processes of urine formation and adjustment of blood composition (top left on page 984), and definitely see Fig. 25.11:

glomerular filtration, tubular reabsorption, tubular secretion

25.4 Urine formation, step 1: The glomeruli make filtrate

GLOMERULAR FILTRATION

( glomerular filtration = a passive process in which hydrostatic pressure forces fluids and solutes from the blood of the glomerulus through the filtration membrane into the capsular space

( glomerular filtration of blood results in the formation of fluid called

glomerular filtrate in the capsular space

The Filtration Membrane

- the filtration membrane lies between what the blood and the capsular space

- it is a porous membrane that allows what?

the free passage of water and solutes smaller than plasma proteins

- substances from the blood must pass through the filtration membrane to get into the capsular space during glomerular filtration

- the filtration membrane consists of three components (see Fig. 25.12):

1. fenestrated endothelium of the glomerular capillaries

( fenestrations are pores in the endothelial cells that prevent filtration of blood cells and platelets

2. basement membrane of the glomerular capillaries

( prevents filtration of larger plasma proteins

3. filtration slits between the foot processes of the podocytes that form the visceral layer of the glomerular capsule

( the visceral layer of the glomerular capsule consists of modified simple squamous cells called podocytes; these podocytes have numerous foot processes that wrap around the endothelial cells of the glomerular capillaries (see Fig. 25.12); the spaces between the foot processes are called filtration slits

( the filtration slits prevent the passage of macromolecules

Pressures that Affect Filtration

glomerular filtration depends on three main pressures:

Outward Pressures – promote filtrate formation:

1. hydrostatic pressure in glomerular capillaries is the pressure exerted by the blood against the walls of the glomerular capillaries

- it is the chief force pushing water and solutes out of the blood and across the filtration membrane into the capsular space

- the blood pressure in the glomerulus is extraordinarily high (55 mm Hg) compared to that in other capillary beds (26 mm Hg), and it remains high across the entire capillary bed.

- as a result, does filtration occur along the entire length of each glomerular capillary?

yes

Inward Pressures – inhibit filtrate formation by opposing hydrostatic pressure in the glomerular capillaries:

2. hydrostatic pressure in the capsular space

- this is the pressure is exerted by what?

filtrate in the glomerular capsule

3. osmotic pressure in glomerular capillaries

- this is the pressure is exerted by what?

proteins in the blood

( see Fig. 25.13 on page 986 to answer the following:

∙ what is the normal value for hydrostatic pressure in the glomerulus? 55 mm Hg

∙ for hydrostatic pressure in the capsular space? 15 mm Hg

∙ for osmotic pressure in glomerular capillaries? 30 mmHg

( Net Filtration Pressure (NFP) is the overall, net pressure that promotes glomerular filtration (it determines glomerular filtration rate)

( we will write the equation that shows how a normal NFP is calculated:

Glomerular Filtration Rate (GFR)

( define glomerular filtration rate (GFR):

= the volume of filtrate formed each minute by the combined activity of all 2 million glomeruli of the kidneys

( glomerular filtration rate is directly proportional to three factors; list (and definitely read about) the three factors:

- net filtration pressure

- total surface area available for filtration

- filtration membrane permeability

( the average GFR in adults is about 125 ml/min

Regulation of Glomerular Filtration

( definitely read the paragraphs under this heading on p. 987; they are a good overview of the next information!

Intrinsic Controls: Renal Autoregulation

( intrinsic controls (renal autoregulation) act locally within the kidney to maintain GFR

- if glomerular filtration does not occur, or if the GFR is too low, waste products in the blood are not excreted, pH control is jeopardized, and an important mechanism for regulating blood volume is lost!

( the kidneys can maintain a nearly constant GFR despite fluctuations in systemic arterial blood pressure (between about 80 to 180 mmHg) by renal autoregulation

( In renal autoregulation, GFR is controlled mainly by changing the diameter of the afferent arterioles, which changes glomerular hydrostatic pressure

( ( if the glomerular hydrostatic pressure rises, what happens to NFP and GFR?

they rise

( if the glomerular hydrostatic pressure falls by as little as 18%, what happens to GFR?

drops to zero

( example of renal autoregulation:

elevated systemic blood pressure causes smooth muscle of afferent arterioles to contract

( narrows the lumen of the afferent arterioles

( blood flow into the glomeruli decreases

( glomerular hydrostatic blood pressure decreases

( reduces NFP and, therefore, GFR to previous normal level

Extrinsic Controls: Neural and Hormonal Mechanisms

( what is the purpose of extrinsic controls (by the nervous and endocrine systems) regulating the GFR?

to maintain systemic blood pressure

- a constant blood pressure is closely tied to GFR in the following ways:

( assuming nothing else changes, an increase in GFR increases urine output, which reduces blood volume and systemic blood pressure

( so what do you think a decrease in GFR does to urine output, blood volume and blood pressure?

- decreases urine output, which increases blood volume and blood pressure

1. Sympathetic Nervous System Controls

( during extreme stress or emergency, when it is necessary to shunt blood to vital organs, neural controls may overcome renal autoregulation

( for example:

with hemorrhage, systemic blood pressure (BP) drops

( causes release of norepinephrine from sympathetic neurons (and epinephrine from the adrenal medulla), which causes:

a. vasoconstriction ( ( peripheral resistance ( ( BP back to normal

b. specifically, vasoconstriction of afferent arterioles ( ( blood flow through glomeruli (

( GFR, which helps restore total blood volume and systemic BP to normal

Renin-Angiotensin-Aldosterone Mechanism

- this is the body’s main mechanism for doing what?

increasing blood pressure

- without adequate blood pressure (such as due to hemorrhage, dehydration, etc.) glomerular filtration is not possible, so this mechanism regulates GFR indirectly by maintaining systemic blood pressure

e.g. A decrease blood volume causes a drop in systemic hydrostatic BP

( a decrease in hydrostatic BP in the afferent arteriole stimulates juxtaglomerular cells in the kidneys to secrete an enzyme called renin into the blood

( renin converts angiotensinogen (in the plasma; produced by the liver) to angiotensin I

( an enzyme produced in the lungs converts angiotensin I to angiotensin II

angiotensin II:

1. causes vasoconstriction of systemic arterioles, which increases blood pressure

2. stimulates the cells of the adrenal cortex to increase aldosterone secretion

( aldosterone increases Na+ reabsorption by the kidney tubules

( more water is reabsorbed due to osmosis, which increases blood volume

( systemic blood hydrostatic pressure increases

3. increases the sensation of thirst, salt desire, and ADH secretion, which increase water resorption

( so, all of the effects of angiotensin II are aimed at restoring total blood volume and systemic blood pressure!

25.5 Urine formation, step 2: Most of the filtrate is reabsorbed into the blood

TUBULAR REABSORPTION = the movement of

substances from the tubular fluid into the blood of the

peritubular capillaries and vasa recta

this is my summary of all the detail in the book!!!:

( as tubular fluid flows along the renal tubule and collecting duct, reabsorption occurs; in other words, substances in the tubular fluid pass from the lumen of the tubule ( through the epithelial cells lining the tubule ( into the blood in surrounding peritubular capillaries and vasa recta

( different substance get reabsorbed through different parts of the renal tubule and by different mechanisms (active transport; diffusion, etc.; see Tale 25.1)

( e.g. of substances that get reabsorbed:

- electrolytes

- amino acids

- glucose (I will go over this in class)

- water - this is important and gets its own heading:

Tubular Reabsorption of Nutrients, Water, and Ions

My Summary Of Water Reabsorption And Influence Of ADH:

( 80% of water in the tubular fluid is reabsorbed from the proximal convoluted tubule (PCT) to the thin segment of the nephron loop. This occurs regardless of the volume and concentration of urine produced by the kidney, and is called obligatory water reabsorption.

( The remaining water that can be reabsorbed from the tubular fluid is variable. It depends on ADH and is called facultative water reabsorption. If ADH is present, more water is reabsorbed from the distal convoluted tubule and collecting duct into the surrounding capillaries. Therefore, more water is reabsorbed into the blood, and less remains in the filtrate.

ADH (antidiuretic hormone)

( ADH is a hormone produced by neurosecretory cells in the hypothalamus of the brain;

it is stored and released into the blood by the posterior pituitary gland

( target of ADH = epithelial cells of the distal convoluted tubules (DCT) and the collecting duct

( effect of ADH = causes the cell membrane of the epithelial cells of the DCT and collecting duct to be more permeable to water; this allows an increase in tubular reabsorption of water and, therefore, a decrease in urine production. (A diuretic is a substance that causes an increase in urine production.)

1. NaCl in the filtrate entering the PCT is actively transported out of the PCT. Water follows by osmosis.

2. The epithelial cells of the descending portion of the nephron loop are freely permeable to water. Water moves out by osmosis, because the interstitial tissue of the medulla of the kidney is hypertonic to the fluid in the tubule.

3. NaCl is actively transported from the ascending portion of the nephron loop into the interstitial tissue, but the epithelium of the thick ascending tubule is NOT permeable to water.

4. As tubular fluid passes through the DCT and the collecting duct, water reabsorption and, therefore, urine volume and concentration now depends on antidiuretic hormone (ADH), because the permeability of the collecting duct and the DCT to water depends on the concentration of ADH in the blood:

a. A drop in blood hydrostatic pressure or an increase in osmotic pressure of the blood stimulates an increase in ADH secretion into the blood

( cells of collecting duct and DCT are more permeable to water

( more water moves out of the DCT and collecting duct by osmosis into the interstitial fluid and into surrounding blood capillaries

( this increase in water reabsorption causes the excretion of a smaller volume of more concentrated urine and the body conserves water

b. A rise in blood hydrostatic pressure or a decrease in osmotic pressure of the blood causes a decrease in ADH secretion

( cells of collecting duct and DCT are less permeable to water and water remains in these tubules as it passes through them

( decrease in water reabsorption and excretion of larger volume of more dilute urine and the body gets rid of excess water

NOTE: The ascending portion of the nephron loop actively transports NaCl from the tubule into the interstitial fluid, but is impermeable to water. Therefore, large quantities of NaCl (and urea) accumulate in the interstitial fluid in increasing concentration from the cortex through the medulla, creating a hypertonic environment.

Other substances (along with ADH) that influence water reabsorption (and, therefore, urine volume and concentration):

⦁ Aldosterone

( see page 9 of the Chapter Outline with respect to the Renin-Angiotensin-Aldosterone Mechanism

⦁ Atrial Natriuretic Peptide

( atrial natriuretic peptide is a hormone secreted from cardiac muscle cells in the right atrium of the heart when blood volume increases and stretches the cardiac muscle cells.

( it reduces Na+ reabsorption in the kidney (in other words it promotes the excretion of water and sodium ions in urine)

( e.g., An increase in blood volume or blood pressure stretches the myocardium

( cardiac muscle cells of the right atrium secrete atrial natriuretic peptide

( atrial natriuretic peptide inhibits Na+ reabsorption from the kidneys

( results in the production of a large volume of dilute urine

( which causes a decrease in blood volume and blood pressure

⦁ Diuretics (page 1000)

Diuretics = chemicals that increase the rate of urine formation.

Examples of diuretics are:

a. alcohol - inhibits release of ADH from the posterior pituitary

b. sodium ion reabsorption inhibitors (loop diuretics; e.g., furosemide)

- decrease the reabsorption of Na+ and CL- from the thick ascending portion of the nephron loop and, therefore, decrease water reabsorption

c. caffeine

- promotes renal vasodilation, which increases GFR

- decreases reabsorption of NaCl ( less water is reabsorbed due to osmosis

d. osmotic diuretics (e.g., mannitol)

- increase the osmotic pressure of the filtrate and, therefore decrease the amount of water that moves out of the filtrate (decrease reabsorption of water)

⦁ Temperature

An increase in body temperature causes:

a. cutaneous blood vessels to dilate

b. vessels to the abdominal organs to constrict ( decrease in blood flow to the kidney

( decrease in GFR ( decrease in volume of urine produced

A decrease in body temperature causes:

a. cutaneous blood vessels to constrict

b. vessels to the abdominal organs to dilate ( increase in blood flow to the kidney

( increase in GFR ( increase in volume of urine produced

25.6 Urine formation, step 3: Certain substances are secreted into the filtrate

TUBULAR SECRETION:

( = tubular secretion is the process of adding substances from the blood into the tubular fluid within the renal tubule; it is like reabsorption in reverse! (check out Fig. 25.11 again!)

( some substances that get secreted are urea, uric acid, K+, H+

( read about the importance of tubular secretion

25.8 Renal function is evaluated by analyzing blood and urine (page 1000)

• what does renal clearance refer to?

the volume of plasma from which the kidneys clear (completely remove) a particular substance in a given time, usually 1 min

• renal clearance tests are done to determine what and what does this allow?

- to determine GFR

- allows to detect glomerular damage and follow the progress of renal disease

• inulin is used to determine the GFR, because it has a renal clear value equal to GFR; it is freely filtered and neither reabsorbed nor secreted by the kidneys

URINE

( Chemical Composition

( water (95%)

( urea - what is urea derived from?

the normal breakdown of amino acids

( uric acid - what is uric acid an end product of?

an end product of nucleic acid metabolism

( creatinine - what is creatinine?

a metabolite of creatine phosphate, which is found in large amounts in skeletal muscle tissue where it stores energy to regenerate ATP

( solutes – what are some normal solutes that constitute urine?

Na+, PO4-3, SO4-2; creatinine, and uric acid

( list the 7 abnormal constituents of urine from Table. 25.3 on p. 1001 and give the name of the condition if each is present:

glucose – glycosuria

proteins – proteinuria, albuminuria

ketone bodies – ketonuria

hemoglobin – hemoglobinuria

bile pigments – bulirubinuria

erythrocytes – hematuria

leukocytes (pus) - pyuria

( Physical Characteristics

Color and Transparency

• describe freshly voided urine:

clear and pale to deep yellow

- the yellow color of urine is due to what?

urochrome, a pigment that results when the body destroys hemoglobin

Odor

• read about the odor of urine

pH

• describe the pH of urine:

usually slightly acidic (around pH 6), but changes in body metabolism or diet may cause the pH to vary from about 4.5 to 8.0

Specific Gravity

• what is the range of specific gravity of urine, and what does it depend on?

1.001 to 1.035, depending on its solute concentration

25.9 The ureters, bladder, and urethra transport, store, and eliminate urine

URETERS

∙ there are 2 ureters, one from each kidney (see Fig. 25.1, Fig. 25.2, and Fig. 25.22)

∙ they are slender tubes that do what?

convey urine from the kidneys to the bladder

∙ about 10-12 inches long.

∙ enter the urinary bladder medially from the posterior side

∙ urine moves by peristalsis, pressure and gravity to the urinary bladder

URINARY BLADDER

∙ describe the urinary bladder:

a smooth, collapsible, muscular sac that stores urine temporarily

Urinary Bladder Anatomy

∙ describe the location of the urinary bladder:

retroperitoneally on the pelvic floor just posterior to the pubic symphysis

∙ the interior of the bladder has openings for what?

both ureters and the urethra

∙ what is the trigone and why is it important clinically?

- the smooth, triangular region of the bladder base outlined by these three openings is the trigone

- important clinically because infections tend to persist in this region

∙ what is the muscular layer of the bladder wall called? the detrusor

- what type of muscle tissue forms this muscular layer? smooth muscle

Urinary Storage Capacity

∙ the urinary bladder is very distensible; please read about it!

∙ usually, a moderately full bladder holds about how much urine?

500 ml (1 pint)

URETHRA

describe the urethra:

a thin-walled muscular tube that drains urine from the bladder and conveys it out of the body

∙ note the two urethral sphincters shown in Fig. 25.22

1. internal urethral sphincter is a thickening of the detrusor muscle at what junction?

the bladder-urethra junction

- it is formed by what type of muscle tissue? smooth muscle

- so, is it voluntary or involuntary? involuntary

2. what does the external urethral sphincter surround? the urethra

- it is formed by what type of muscle tissue? skeletal muscle

- so, is it voluntary or involuntary? voluntary

∙ the urethra opens to the outside at the external urethral orifice

∙ how long (in inches) is the urethra in females? 3 to 4 cm (1.5 in)

∙ how long (in inches) is the urethra in males? 20 cm (8 in)

- list the three regions of the urethra in males (we’ll get back to this with the reproductive system):

prostatic urethra

intermediate part of the urethra (membranous)

spongy urethra

MICTURITION

( what is micturition also called? urination or voiding

( define micturition:

the act of emptying the urinary bladder

( in order for micturition to occur, list the three things that must happen simultaneously:

(1) the detrusor must contract

(2) the internal urethral sphincter must open

(3) the external urethral sphincter must open

( when the urinary bladder is stretched (beginning with about 200 to 400 ml of urine), stretch receptors initiate sensory nerve impulses to the sacral region of the spinal cord

( the sacral region of the spinal cord sends:

1. increased parasympathetic impulses that cause:

a. the internal urethral sphincter to open

b. cause contraction of the smooth muscle of the bladder wall (the detrusor muscle)

2. decreased somatic motor impulses that cause the external urethral sphincter to open

( urination occurs (!

( urination is a simple spinal reflex in infants, but after about 2 years of age, it can be initiated or stopped voluntarily by impulses from the cerebral cortex that override the reflex

THE END!

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Glomerular filtrate contains water and most solutes found in blood plasma; it lacks formed elements and large proteins

Renin-Angiotensin Aldosterone Mechanism

stimulates vasoconstriction of systemic arterioles

(

( systemic blood pressure

( blood volume

(

( systemic blood pressure

(

detected as blood flows through afferent arterioles

(

release of renin from kidneys

(

leads to the formation of

angiotensin II

in the blood

stimulates outer zone of

adrenal cortex to

( aldosterone production

(

causes kidneys to

( Na+ reabsorption into the blood

(

water follows due to osmosis so

( water reabsorption

(

( blood volume

(

( systemic blood pressure

( sensation of thirst, salt desire, and ADH secretion

(

( water reabsorption by kidneys into the blood

(

( blood volume

(

( systemic blood pressure

( Once the glomerular filtrate begins to flow from the capsular space into the renal tubule, it is referred to as tubular fluid.

What if you are dehydrated on a hot summer day,

would more or less ADH be secreted? would more or less water be reabsorbed?

would more or less urine be produced?

What if you drink too much water,

would more or less ADH be secreted? Would more or less water be reabsorbed?

would more or less urine be produced?

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