Chapter 31: Urinary System

Question 1

Objectives:

• Discuss the components and functions of the urinary system.
• Discuss the role the kidneys play in homeostasis of water and electrolytes. Correlate this with the cardiovascular system.

Answer 1

fyi

Question 2

The urinary system

It Processes incoming blood plasma in ways that allow it to leave the kidney in better condition

what 3 things does it adjust?

Answer 2

• Adjusts water content
• Adjusts blood plasma ions (sodium & potassium)
• Adjusts blood pH

Question 3

red

function of what?

to process blood and form urine as waste (empties into ureters)

Answer 3

Kidney

Question 4

Shape, size, and location

• Roughly oval with a medial indentation
• Approximately 11 cm × 7 cm × 3 cm
• Left kidney often larger than the right; right located a little lower
• Both kidneys located in a retroperitoneal position
• Lie on either side of the vertebral column between T12 and L3
• Superior poles of both kidneys extend above the level of the twelfth rib and the above lower edge of the thoracic parietal pleura

This is the structure of what

Answer 4

Kidney- Gross structure (Figure 31-1)

Question 5

Structure: collapsible bag located behind the pubic symphysis made mostly of crisscrossing smooth muscle tissue.

Answer 5

Urinary bladder (Figures 31-5 and 31-6)

Question 6

_Urinary bladder (Figures 31-5 and 31-6)_
 collapsible bag located behind the pubic symphysis made mostly of crisscrossing smooth muscle tissue.

what is the name of this muscle?

Answer 6

detrusor muscle

Question 7

What are these the functions of?

• Reservoir for urine before it leaves the body
• Aided by the urethra, it expels urine from the body

Answer 7

Urinary bladder (Figures 31-5 and 31-6)

Question 8

Small mucous membrane–lined tube extending from the trigone (part of the bladder) to the exterior of the body

Answer 8

Urethra

Question 9

In females where does the urethra lie?

Answer 9

it lies posterior to the pubic symphysis and anterior to the vagina. It is approximately 3 cm long (Figure 31-4).

Question 10

In males where does the urethra lie?

Answer 10

after leaving the bladder, it passes through the prostate gland where it is joined by two ejaculatory ducts from the prostate. It extends to the base of the penis, then through the center of the penis, ending as the urinary meatus. It is approximately 20 cm long and is part of both the urinary and reproductive systems.

Question 11

Mechanism for voiding the bladder

Answer 11

urination or micturition

Question 12

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what is it describing below?

• As bladder volume increases, involuntary micturition contractions (of detrusor muscle) increase and the internal urethral sphincter muscles relaxes (Figure 31-5). This combination of muscle contraction and relaxation forces the urine out.
• The external urethral sphincter muscles (including the levator ani) can be voluntarily contracted to stop urine until urination is appropriate. They are consciously relaxed when you are ready to release urine. Voluntary control of urination is made possible by nerves supplying the pelvic floor.

Answer 12

urination

Question 13

the microscopic functional units that comprise the bulk of the kidney. Each one is made of two regions (renal corpuscle and renal tubule) and connects to a shared collecting duct (Figure 31-10)

Answer 13

Nephrons

Question 14

Each nephron is made of what two regions

Answer 14

• renal corpuscle
• renal tubule

Question 15

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regiion of the nephron that Filters fluid out of the blood

Answer 15

Renal corpuscle

Question 16

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regiion of the nephron that Either returns filtrate to blood or passes it on to be eventually secreted as urine. Primary function is reabsorption

Answer 16

Renal tubule

Question 17

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This corpuscle Is made of the glomerulus tucked inside a Bowman capsule (Figures 28-11 to 28-13); located within the cortex of the kidney

Answer 17

Renal

Question 18

This is where the renal corpuscle in tucked inside:

cup-shaped mouth of the nephron that collects filtrate from the glomerular capillaries

Answer 18

Bowman capsule

Question 19

what is being described below?

• Formed by parietal and visceral walls with a space between them (like a fist inside a balloon)(Figures 31-11)
• The outer layer is not involved in filtration.
• The inner layer contains filtration slits within connective tissue. The connective tissue acts as a diaphragm and controls the size of the opening, therefore preventing large molecules (proteins) from escaping.

Answer 19

Bowman capsule

Question 20

network of fine capillaries surrounded by Bowman capsule

Answer 20

Glomerulus

Question 21

RENAL CORPUSCLE /Glomerulus

pores in capillary walls that permit filtration to the inner layer of the Bowman’s capsule (not found in other capillaries)

Answer 21

Fenestrations

Question 22

red

the renal corpuscle’s Basement membrane lies between what two structures?

Answer 22

• glomerulus
• Bowman capsule

Question 23

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formed by glomerular endothelium, basement membrane, and the visceral layer of Bowman capsule; the function is filtration

Answer 23

Glomerular capsular filtration membrane (figure 31-15)

Question 24

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*One of the 2 principle parts of the nephron.
-It is a winding or convoluted tube that receives filtrate from the Bowman’s capsule and transports it to the collecting duct.

Answer 24

Renal tubule

Question 25

Renal tubule During transportation, some of its filtrate is __________ Additional substances are also added to the remaining filtrate in the process of urine formation. Along with other tubules, it joins a common collecting duct

Answer 25

reabsorbed. (this one word was red)

Question 26

red ## Footnote 3 PARTS OF THE RENAL TUBULE (figure 31-10)

Answer 26

- Proximal convoluted tubule - Henle loop - Distal convoluted tubule

Question 27

red ## Footnote first part of the renal tubule nearest to Bowman capsule; follows a winding, convoluted course

Answer 27

Proximal convoluted tubule

Question 28

red ## Footnote - Renal tubule segment just beyond the proximal tubule - Consists of a thin descending limb, a sharp turn, and an ascending limb; ascending limb made of thin ascending limb followed by thick ascending limb

Answer 28

Henle loop

Question 29

red ## Footnote - convoluted tubule beyond the Henle loop - Along with other distal tubules, it joins a common collecting duct

Answer 29

Distal convoluted tubule

Question 30

Straight duct made up of the renal tubules of several nephrons. \_\_\_\_\_\_\_\_\_\_\_\_\_of one renal pyramid converge to form one tube that opens at a renal papilla into a minor calyx (Figure 31-16)

Answer 30

COLLECTING DUCT

Question 31

Blood supply of the nephron (Figure 28-17)

Answer 31

- Afferent arteriole - Efferent arteriole

Question 32

red ## Footnote Blood supply of the nephron (Figure 28-17) -enters glomerular capillary network

Answer 32

Afferent arteriole

Question 33

red ## Footnote Blood supply of the nephron (Figure 28-17) that leaves glomerulus enters a capillary network that runs alongside the renal tubule called the peritubular blood supply

Answer 33

Efferent arteriole

Question 34

red Efferent arteriole Some of this blood supply follows into the nephron loop, these vessels are called the \_\_\_\_\_\_\_\_\_\_\_\_. Because these vessels are in close proximity to the nephron, it allows for efficient transferring of substances to and from the blood.

Answer 34

-vasae rectae

Question 35

red ## Footnote The basic functional unit of the kidney is the nephron; it forms urine by three processes (Figure 31-18)?

Answer 35

red 1. Filtration 2. Tubular reabsorption 3. Tubular secretion

Question 36

movement of water and protein-free solutes from plasma ***_in the glomerulus into the capsular space of Bowman capsule_***

Answer 36

Filtration

Question 37

movement of molecules out of the tubule and into peritubular blood. **_It is the second step in urine formation and occurs as a result of passive and active transport mechanisms from all parts of the renal tubules. The major portion of reabsorption occurs in the proximal convoluted tubules (Figure 31-18)._**

Answer 37

Tubular reabsorption

Question 38

movement of molecules out of peritubular blood and into the tubule for excretion. : **_the movement of substances out of the blood and into tubular fluid, becomes part of the urine_**

Answer 38

Tubular secretion

Question 39

red ## Footnote Most water and solutes are recovered by the blood, leaving only a small volume of tubule fluid left to move on

Answer 39

Reabsorption

Question 40

red ## Footnote actively transported (requires energy) out of tubule fluid and into blood (Figure 31-21)

Answer 40

Sodium

Question 41

fyi red ## Footnote Proximal tubule drains Bowman’s capsule and is where almost complete absorption of nutritionally important substances takes place.

Answer 41

fyi

Question 42

passively transported out of tubule

Answer 42

Glucose and amino acids

Question 43

ions passively move into blood

Answer 43

Chloride, phosphate, and bicarbonate

Question 44

movement of sodium and chloride into blood causes an osmotic imbalance, moving water passively into blood

Answer 44

Water

Question 45

approximately half of urea passively moves out of the tubule, with the remaining urea moves on to the Henle loop

Answer 45

Urea

Question 46

This area reabsorbs water and ions from the urine and plays a role in controlling the concentration of urine

Answer 46

HENLE LOOP

Question 47

HENLE LOOP - Water is reabsorbed from the tubule fluid in the descending limb - Sodium and chloride are reabsorbed from the filtrate in the ascending limb, where the reabsorption of salt makes the tubule fluid dilute

Answer 47

Reabsorption

Question 48

HENLE LOOP Descending limb of the Henle loop secretes urea by diffusion

Answer 48

Secretion

Question 49

These areas regulate potassium, sodium and pH. Further dilution of urine takes place here.

Answer 49

DISTAL CONVOLUTED TUBULE & COLLECTING DUCT

Question 50

DISTAL CONVOLUTED TUBULE & COLLECTING DUCT Sodium by active transport but in smaller amounts than in the proximal convoluted tubule

Answer 50

Reabsorption

Question 51

DISTAL CONVOLUTED TUBULE & COLLECTING DUCT 2 Hormones help initiate action reabsorption

Answer 51

- Aldosterone - Antidiuretic hormone (ADH)

Question 52

hormone that targets the cells of the distal tubule and collecting duct cells and causes **_increased activity of the sodium-potassium pump. It also increases the reabsorption of water into the kidney tubules._**

Answer 52

Aldosterone

Question 53

is secreted by the posterior pituitary and targets the cells of distal tubules and collecting ducts to **_make them reabsorb water (Figure 31-26)_**

Answer 53

Antidiuretic hormone (ADH)

Question 54

DISTAL CONVOLUTED TUBULE & COLLECTING DUCT Continued -Secretion

Answer 54

- Potassium, - hydrogen - ammonium ions

Question 55

red ## Footnote Regulation of urine volume (Figure 31-27) what 3 hormones

Answer 55

ADH Aldosterone Atrial natriuretic hormone

Question 56

what hormore influences water reabsorption by reducing water loss

Answer 56

ADH

Question 57

what hormore **_increases distal tubule absorption of sodium, thereby raising the sodium concentration of blood and thus promoting reabsorption of water_**

Answer 57

Aldosterone

Question 58

what hormone is **_secreted by atrial muscle fibers, promotes loss of sodium by urine; opposes aldosterone, thus causing the kidneys to reabsorb less water and thereby produce more urine_**

Answer 58

Atrial natriuretic hormone

Question 59

\*\*\*\*approximately 95% water with several substances dissolved in it; most important include: - Nitrogenous wastes: - Electrolytes: - Toxins: - Pigments - Hormones: - Abnormal constituents (e.g., blood, glucose, albumin, casts, calculi)

Answer 59

Urine composition

Question 60

result of protein metabolism; include urea, uric acid, ammonia, and creatinine

Answer 60

Nitrogenous wastes:

Question 61

mainly the following ions: **_sodium, potassium, ammonium, chloride, bicarbonate, phosphate, and sulfate;_** amounts and kinds of minerals vary with diet and other factors

Answer 61

Electrolytes

Question 62

during disease, bacterial poisons leave the body in urine

Answer 62

Toxins

Question 63

fyi high hormone levels may spill into the filtrate in urine composition

Answer 63

fyi

Question 64

Abnormal constituents

Answer 64

(e.g., blood, glucose, albumin, casts, calculi)

Question 65

THE BIG PICTURE: URINARY SYSTEM AND THE WHOLE BODY

Answer 65

- Homeostasis of water and electrolytes in body fluids relies on proper functioning of the kidneys; nephrons process blood to adjust its content to maintain a relatively constant internal environment - **_The Urinary system secretion refers to the movement of substances from the bloodstream to the tubule of the nephron._** - Urinary and cardiovascular systems are interdependent - Endocrine and nervous systems must operate properly to ensure efficient kidney function * *-The medullary region of the kidney contains the nephrons, interlobular arteries, and the renal pyramids.**