Module 4 - Renal homework chapter 24

Question 1

What are the main functions of the urinary system?

Answer 1

Filters Blood & Removes Waste, Regulates Fluid Balance, Balances Electrolytes, Controls Blood pH, Regulates Blood Pressure, Produces Hormones

Main functions include eliminating urea, controlling body water levels, managing ion levels, maintaining acid-base balance, influencing blood volume, and producing erythropoietin and activating Vitamin D.

Question 2

What do the kidneys do?

Answer 2

Filter Blood, Control Fluids, Balance Electrolytes, Regulate Blood Pressure, Maintain Blood pH, Produce Hormones

Key functions include removing waste products, regulating water balance, managing salt levels, producing renin, and activating Vitamin D.

Question 3

What stimulates urination?

Answer 3

Stretching of the bladder wall

The urge to urinate is triggered as the bladder fills with urine.

Question 4

What is the definition of kidneys?

Answer 4

Bean-shaped organs that filter waste from blood and produce urine.

Question 5

What is urine?

Answer 5

Liquid waste product made by the kidneys, containing water, urea, and salts.

Question 6

What is the urinary tract?

Answer 6

The pathway (ureters, bladder, urethra) for urine to exit the body after being made by the kidneys.

Question 7

What are the two main internal layers of the kidney?

Answer 7

Outer renal cortex and inner renal medulla.

Question 8

What is the nephron?

Answer 8

The microscopic filtering unit of the kidney that produces urine.

Question 9

What is glomerular filtration?

Answer 9

Initial filtering of blood plasma from the glomerulus into the nephron capsule.

Question 10

What is tubular reabsorption?

Answer 10

Moving useful substances from the filtrate back into the bloodstream.

Question 11

What is tubular secretion?

Answer 11

Actively moving additional waste products from the blood into the filtrate.

Question 12

What does GFR stand for?

Answer 12

Glomerular Filtration Rate.

Question 13

What primarily drives glomerular filtration?

Answer 13

Glomerular hydrostatic pressure (GHP).

Question 14

What is the filtration membrane?

Answer 14

Barrier (capillary wall, basement membrane, podocytes) filtering blood in the glomerulus.

Question 15

What are podocytes?

Answer 15

Specialized cells with foot processes covering glomerular capillaries, forming filtration slits.

Question 16

What is net filtration pressure?

Answer 16

Overall pressure driving filtration out of the glomerulus (GHP - GCOP - CHP).

Question 17

What is the role of the juxtaglomerular apparatus?

Answer 17

Regulates blood pressure and filtration rate.

Question 18

What does the renin-angiotensin-aldosterone system do?

Answer 18

Regulates blood pressure and fluid balance.

Question 19

What is the major site of reabsorption in the nephron?

Answer 19

Proximal tubule.

Question 20

Fill in the blank: The _______ is a U-shaped tube in the nephron involved in concentrating urine.

Answer 20

Nephron loop.

Question 21

True or False: The kidneys receive a very high percentage of blood flow relative to their size.

Answer 21

True.

Question 22

What does the term ‘cortical nephron’ refer to?

Answer 22

Nephron located primarily in the renal cortex with a short loop of Henle.

Question 23

What does the term ‘juxtamedullary nephron’ refer to?

Answer 23

Nephron near the medulla with a long loop of Henle extending deep into the medulla; important for concentrating urine.

Question 24

What is the main job of the urinary system?

Answer 24

To filter waste from blood and regulate fluid balance.

Question 25

What key hormones do the kidneys produce or activate?

Answer 25

Erythropoietin (EPO), renin, and active Vitamin D (calcitriol).

Question 26

Where does glomerular filtration occur?

Answer 26

Renal corpuscle (from glomerulus into Bowman's capsule).

Question 27

Where does tubular reabsorption primarily occur?

Answer 27

Along the renal tubules (Proximal Tubule, Nephron Loop, Distal Tubule) and collecting ducts.

Question 28

Where does tubular secretion primarily occur?

Answer 28

Along the renal tubules (mainly Proximal and Distal Tubules) and collecting ducts.

Question 29

What does tubuloglomerular feedback respond to?

Answer 29

Increases in GFR (glomerular filtration rate) ## Footnote This mechanism is crucial for maintaining homeostasis in kidney function.

Question 30

What is the role of the renin-angiotensin-aldosterone system (RAAS) in regulating systemic blood pressure?

Answer 30

Increases BP through vasoconstriction (Angiotensin II) and increased blood volume (Aldosterone promoting Na+/water retention) ## Footnote RAAS plays a critical role in long-term blood pressure regulation.

Question 31

How does RAAS help maintain GFR during low blood pressure?

Answer 31

By constricting the efferent arteriole more than the afferent (via Angiotensin II) ## Footnote This adjustment helps counteract decreases in renal blood flow.

Question 32

What is the definition of paracellular route in nephron function?

Answer 32

Substances pass between adjacent tubule cells.

Question 33

What is the definition of transcellular route in nephron function?

Answer 33

Substances pass through tubule cells (crossing apical and basolateral membranes).

Question 34

What is obligatory water reabsorption?

Answer 34

Water reabsorbed passively following solutes (osmosis), mainly in the proximal tubule; independent of hormones.

Question 35

What is facultative water reabsorption?

Answer 35

Hormone-regulated (ADH) water reabsorption occurring in the distal tubule and collecting duct, adjusting based on hydration.

Question 36

What hormone increases water permeability in the distal tubule and collecting ducts?

Answer 36

Antidiuretic hormone (ADH) ## Footnote This hormone promotes water reabsorption.

Question 37

What is the main difference in direction between tubular reabsorption and secretion?

Answer 37

Reabsorption moves substances from filtrate to blood; secretion moves substances from blood to filtrate.

Question 38

Where does the majority of solute and water reabsorption occur in the nephron?

Answer 38

Proximal Convoluted Tubule (PCT).

Question 39

What role do sodium ions play in the reabsorption of water and other solutes?

Answer 39

Creating an osmotic gradient and facilitating co-transport of solutes.

Question 40

Where is the majority of sodium reabsorption located in the nephron?

Answer 40

Proximal convoluted tubule, Loop of Henle, Distal convoluted tubule, and collecting duct.

Question 41

How does reabsorption differ in the proximal and distal tubules?

Answer 41

Proximal tubule: Massive, non-regulated reabsorption; Distal tubule: Fine-tuned, hormonally regulated reabsorption.

Question 42

What is the primary hormone regulating water reabsorption in the collecting duct?

Answer 42

ADH (antidiuretic hormone).

Question 43

What happens to urine volume and composition when aldosterone is secreted?

Answer 43

Increases Na+ reabsorption, K+ secretion; reduces urine volume, increases K+ in urine.

Question 44

What is the medullary osmotic gradient?

Answer 44

Increasing solute concentration in the kidney's medulla.

Question 45

What is the countercurrent mechanism?

Answer 45

Fluid flow in opposite directions to establish a gradient.

Question 46

What does renal clearance measure?

Answer 46

Volume of plasma kidneys clear of a substance per unit time.

Question 47

What does a high level of protein in a urinalysis indicate?

Answer 47

Possible kidney damage.

Question 48

What are the normal components of urine?

Answer 48

Water, urea, ions (Na+, K+, Cl-), creatinine, uric acid.

Question 49

What substances should not be present in urine under normal conditions?

Answer 49

Glucose, proteins, blood cells, ketones.

Question 50

How can renal clearance be used to estimate the glomerular filtration rate?

Answer 50

Measure creatinine clearance; results approximate GFR.

Question 51

What happens to urine production when ADH is secreted in lower amounts?

Answer 51

Produces dilute urine due to fewer aquaporins in the collecting duct.

Question 52

What is the role of the vasa recta in maintaining the medullary osmotic gradient?

Answer 52

Parallel, opposite blood flow minimizes gradient disruption.

Question 53

How can renal clearance be used to estimate the glomerular filtration rate?

Answer 53

By measuring creatinine clearance ## Footnote Creatinine is freely filtered and minimally reabsorbed/secreted, making clearance value approximate GFR.

Question 54

What are the structures involved in urine transport and storage?

Answer 54

Ureters, urinary bladder, urethra ## Footnote These organs are responsible for transporting urine from the kidneys and storing it.

Question 55

What is the function of the ureter?

Answer 55

Tube connecting kidney to bladder

Question 56

What is the primary function of the urinary bladder?

Answer 56

Stores urine

Question 57

What is the detrusor muscle?

Answer 57

Bladder wall muscle, expels urine

Question 58

What is the trigone?

Answer 58

Triangular area in bladder, ureter/urethra openings

Question 59

What does the urethra do?

Answer 59

Tube from bladder to outside

Question 60

What is micturition?

Answer 60

Urination

Question 61

What is the micturition reflex?

Answer 61

Spinal reflex controlling urination

Question 62

How does urine move from the kidneys to the bladder?

Answer 62

Via peristalsis in the ureters

Question 63

What muscle contracts to expel urine from the bladder?

Answer 63

Detrusor muscle

Question 64

What controls the external urethral sphincter, enabling voluntary urination?

Answer 64

Somatic nervous system

Question 65

How do the male and female urinary tracts differ?

Answer 65

Male: longer urethra, shared with reproductive system; Female: shorter urethra, separate from reproductive system

Question 66

What part of the nervous system mediates the micturition reflex?

Answer 66

Parasympathetic NS

Question 67

How does the central nervous system exert voluntary control over micturition?

Answer 67

Via somatic NS (cerebral cortex)

Question 68

What are the main functions of the urinary system?

Answer 68

Filters blood, eliminates waste, regulates fluid/electrolytes

Question 69

What do the kidneys do?

Answer 69

Forms urine, regulates blood composition/pH

Question 70

What stimulates urination?

Answer 70

Bladder distension