The Urinary System Flashcards

1
Q

Definition

A hormone that increases water reabsorption in the distal tubule and collecting duct.

A

Define

Antidiuretic Hormone (ADH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Definition

The process where stretch receptors in the bladder send impulses to the spinal cord and brain as the bladder fills.

A

Define

Urinary Reflex Action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Definition

The blood vessel that supplies blood to the kidneys.

A

Define

Renal Artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Definition

The part of the nephron that includes the glomerulus and Bowmanโ€™s capsule, where filtration begins.

A

Define

Renal Corpuscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Definition

The cup-like structure that collects urine from the renal papillae.

A

Define

Minor Calyx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define

Perirenal Fat

A

A layer of fat surrounding the kidneys, providing protection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define

Uric Acid

A

A nitrogenous waste from nucleic acid breakdown.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Define

Renal Pyramid

A

Structures in the renal medulla where collecting ducts end at the papillae.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Definition

The structure surrounding the glomerulus that collects the filtrate.

A

Define

Glomerular Capsule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Definition

The barrier between the glomerular capillaries and the glomerular capsule.

A

Define

Filtration Membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Define

Minor Calyx

A

The cup-like structure that collects urine from the renal papillae.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Define

Tubular Reabsorption

A

The process by which essential substances are reclaimed from the filtrate back into the blood.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define

Renal Pelvis

A

The basin-like structure where urine collects before entering the ureter.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Define

Tubular Secretion

A

The process of adding substances from the blood into the filtrate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Define

Ureter

A

The tube that transports urine from the renal pelvis to the bladder.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Define

Renal Vein

A

The blood vessel that drains blood away from the kidneys.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Definition

The small artery that carries blood toward the glomerulus in the nephron.

A

Define

Afferent Arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Define

Short-term Controls

A

Quick adjustments to blood pressure, such as those that occur when changing positions or during acute stress.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Definition

A funnel-shaped structure in the kidney that collects urine from the nephrons and channels it to the ureter.

A

Define

Renal Pelvis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Definition

The primary organs of the urinary system, responsible for filtering blood, producing urine, and regulating various body functions.

A

Define

Kidneys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Define

Detrusor Muscle

A

Smooth muscle in the bladder wall that contracts to facilitate urination.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Define

Urinary Reflex Action

A

The process where stretch receptors in the bladder send impulses to the spinal cord and brain as the bladder fills.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Definition

Structures in the renal medulla where collecting ducts end at the papillae.

A

Define

Renal Pyramid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Define

Urinary System (Renal System)

A

The system responsible for producing, storing, and eliminating urine. It includes the kidneys, ureters, urinary bladder, and urethra.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Definition

A smooth muscle sphincter that controls the release of urine from the bladder.

A

Define

Internal Urethral Sphincter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Definition

The final segment of the renal tubule where hormonal regulation of water and solute reabsorption occurs.

A

Define

Collecting Duct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Define

Retroperitoneal

A

Refers to organs, such as the kidneys, that are located behind the peritoneal cavity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Define

Renin-Angiotensin-Aldosterone System (RAAS)

A

A hormonal cascade initiated by low blood pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Definition

Smooth muscle in the bladder wall that contracts to facilitate urination.

A

Define

Detrusor Muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Define

Osmotic Diuresis

A

A condition where high levels of solutes in the filtrate lead to increased urine production.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Definition

A hormone that increases peripheral vascular resistance and blood pressure.

A

Define

Angiotensin II

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Definition

The organ that stores urine until it is excreted.

A

Define

Bladder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Define

Tubuloglomerular Feedback

A

A process where macula densa cells detect changes in filtrate solute concentration and flow rate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Define

Renal Medulla

A

The inner region of the kidney, containing the renal pyramids and parts of the nephrons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Define

Antidiuretic Hormone (ADH)

A

A hormone that increases water reabsorption in the distal tubule and collecting duct.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Define

Myogenic Mechanism

A

A response where vascular smooth muscle contracts in response to stretch from increased blood pressure, reducing GFR.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Define

Renal Pelvis

A

A funnel-shaped structure in the kidney that collects urine from the nephrons and channels it to the ureter.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Definition

The blood vessel that drains blood away from the kidneys.

A

Define

Renal Vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Define

Intrinsic Mechanisms

A

The kidneyโ€™s internal mechanisms to regulate GFR.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Define

Kidneys

A

The primary organs of the urinary system, responsible for filtering blood, producing urine, and regulating various body functions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Definition

The kidneyโ€™s internal mechanisms to regulate GFR.

A

Define

Intrinsic Mechanisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Definition

Quick adjustments to blood pressure, such as those that occur when changing positions or during acute stress.

A

Define

Short-term Controls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Definition

A hormonal cascade initiated by low blood pressure.

A

Define

Renin-Angiotensin-Aldosterone System (RAAS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Definition

The density of urine compared to water, reflecting the concentration of solutes.

A

Define

Specific Gravity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Definition

A metabolite from muscle activity.

A

Define

Creatinine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Definition

A tight collection of capillaries in the nephron where filtration of blood occurs, surrounded by the Bowmanโ€™s capsule.

A

Define

Glomerulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Define

Glomerular Capsule

A

The structure surrounding the glomerulus that collects the filtrate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Define

Urethra

A

The tube through which urine exits the body from the bladder.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Define

Internal Urethral Sphincter

A

A smooth muscle sphincter that controls the release of urine from the bladder.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Definition

Substances in urine that may indicate health issues:

Blood: Presence can indicate damage to glomerular capillaries or infections.
Bile: Presence can result in a brown color, often indicating liver disease or bile duct obstruction.
Glucose: Presence suggests poorly controlled diabetes mellitus.
Proteins: Their presence can indicate damage to the filtration membrane.

A

Define

Abnormal Constituents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Define

Major Calyx

A

Larger cup-like structures that collect urine from the minor calyces.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Define

Efferent Arteriole

A

The small artery that carries blood away from the glomerulus after filtration.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Define

Blood Pressure Regulation

A

The process of maintaining a constant blood pressure to ensure adequate delivery of oxygen and nutrients to cells and removal of waste.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Define

Abnormal Constituents

A

Substances in urine that may indicate health issues:

Blood: Presence can indicate damage to glomerular capillaries or infections.
Bile: Presence can result in a brown color, often indicating liver disease or bile duct obstruction.
Glucose: Presence suggests poorly controlled diabetes mellitus.
Proteins: Their presence can indicate damage to the filtration membrane.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Definition

The small artery that carries blood away from the glomerulus after filtration.

A

Define

Efferent Arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Define

Atrial Natriuretic Peptide (ANP)

A

A hormone that inhibits sodium and water reabsorption in the distal tubule and collecting duct.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Define

Renal Artery

A

The blood vessel that supplies blood to the kidneys.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Define

External Urethral Sphincter

A

A skeletal muscle sphincter that controls the release of urine voluntarily.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Define

Aldosterone

A

A hormone that increases sodium reabsorption and potassium secretion in the distal tubule and collecting duct.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Define

Urinary Voluntary Control

A

The ability to consciously relax or contract the external sphincter to control urination.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Define

Filtration Membrane

A

The barrier between the glomerular capillaries and the glomerular capsule.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Definition

Larger cup-like structures that collect urine from the minor calyces.

A

Define

Major Calyx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Definition

Refers to organs, such as the kidneys, that are located behind the peritoneal cavity.

A

Define

Retroperitoneal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Definition

The ability to consciously relax or contract the external sphincter to control urination.

A

Define

Urinary Voluntary Control

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Definition

The process of adding substances from the blood into the filtrate.

A

Define

Tubular Secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

Definition

A major solute in urine, produced from the breakdown of amino acids.

A

Define

Urea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

Definition

A response where vascular smooth muscle contracts in response to stretch from increased blood pressure, reducing GFR.

A

Define

Myogenic Mechanism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Define

Extrinsic Mechanisms

A

External regulatory mechanisms that influence GFR.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Definition

The inner region of the kidney, containing the renal pyramids and parts of the nephrons.

A

Define

Renal Medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Define

Angiotensin II

A

A hormone that increases peripheral vascular resistance and blood pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

Definition

A hormone that inhibits sodium and water reabsorption in the distal tubule and collecting duct.

A

Define

Atrial Natriuretic Peptide (ANP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

Definition

A process where macula densa cells detect changes in filtrate solute concentration and flow rate.

A

Define

Tubuloglomerular Feedback

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

Define

Creatinine

A

A metabolite from muscle activity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Define

Renal Cortex

A

The outer region of the kidney, containing the majority of nephrons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

Definition

The process of maintaining a constant blood pressure to ensure adequate delivery of oxygen and nutrients to cells and removal of waste.

A

Define

Blood Pressure Regulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

Define

Nephron

A

The functional unit of the kidney responsible for filtering blood and forming urine, consisting of the glomerulus and renal tubule.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

Definition

A nitrogenous waste from nucleic acid breakdown.

A

Define

Uric Acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

Define

Glomerular Filtration Rate (GFR)

A

The total volume of filtrate formed per minute by all renal nephrons in the kidneys.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

Define

Specific Gravity

A

The density of urine compared to water, reflecting the concentration of solutes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

Define

Renal Corpuscle

A

The part of the nephron that includes the glomerulus and Bowmanโ€™s capsule, where filtration begins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

Define

Urea

A

A major solute in urine, produced from the breakdown of amino acids.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

Definition

A skeletal muscle sphincter that controls the release of urine voluntarily.

A

Define

External Urethral Sphincter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

Definition

External regulatory mechanisms that influence GFR.

A

Define

Extrinsic Mechanisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

Definition

The outer region of the kidney, containing the majority of nephrons.

A

Define

Renal Cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

Definition

The total volume of filtrate formed per minute by all renal nephrons in the kidneys.

A

Define

Glomerular Filtration Rate (GFR)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

Define

Glomerulus

A

A tight collection of capillaries in the nephron where filtration of blood occurs, surrounded by the Bowmanโ€™s capsule.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

Definition

The system responsible for producing, storing, and eliminating urine. It includes the kidneys, ureters, urinary bladder, and urethra.

A

Define

Urinary System (Renal System)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

Define

Collecting Duct

A

The final segment of the renal tubule where hormonal regulation of water and solute reabsorption occurs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

Define

Bladder

A

The organ that stores urine until it is excreted.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

Definition

A condition where high levels of solutes in the filtrate lead to increased urine production.

A

Define

Osmotic Diuresis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

Definition

The tube through which urine exits the body from the bladder.

A

Define

Urethra

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

Definition

The functional unit of the kidney responsible for filtering blood and forming urine, consisting of the glomerulus and renal tubule.

A

Define

Nephron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

Definition

A hormone that increases sodium reabsorption and potassium secretion in the distal tubule and collecting duct.

A

Define

Aldosterone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

Definition

The basin-like structure where urine collects before entering the ureter.

A

Define

Renal Pelvis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

Definition

The tube that transports urine from the renal pelvis to the bladder.

A

Define

Ureter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

Definition

The process by which essential substances are reclaimed from the filtrate back into the blood.

A

Define

Tubular Reabsorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

Define

Afferent Arteriole

A

The small artery that carries blood toward the glomerulus in the nephron.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

Definition

A layer of fat surrounding the kidneys, providing protection.

A

Define

Perirenal Fat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

What is another term commonly used to refer to the urinary system?

A

The renal system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

What are the primary organs of the urinary system?

A

Kidneys, ureters, urinary bladder, and urethra.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

Where are the kidneys located in the body?

A

Between the T12 and L3 vertebrae, with the right kidney slightly lower than the left.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

What protective structures surround each kidney?

A

A tough fibrous capsule and a layer of perirenal fat.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

How much fluid do the kidneys filter from the bloodstream daily?

A

Nearly 200 liters.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

What are the main functions of the kidneys besides urine production?

A

Regulating fluid and electrolyte balance, excreting metabolic wastes, maintaining acid-base balance, regulating blood pressure, and playing a role in erythropoiesis and vitamin D activation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

Which hormone produced by the kidneys regulates red blood cell production?

A

Erythropoietin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

What role does the enzyme renin play in the renal system?

A

It regulates blood pressure by controlling blood volume.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

What is the functional unit of the kidney?

A

The nephron.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

Name the two main parts of a nephron.

A

The renal corpuscle and the renal tubule.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

What are the three main processes involved in urine formation?

A

Glomerular filtration, tubular reabsorption, and tubular secretion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
110
Q

What is the glomerulus, and what is its function?

A

A tightly packed collection of capillaries in the renal corpuscle, specialized for filtration.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
111
Q

Where does tubular reabsorption primarily occur?

A

In the proximal tubule of the nephron.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
112
Q

What percentage of nephrons are cortical nephrons?

A

About 85%.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
113
Q

Which type of nephron is primarily involved in forming concentrated urine?

A

Juxtamedullary nephrons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
114
Q

Trace the pathway of urine from the kidney to outside the body.

A

Collecting ducts โ†’ Renal pelvis โ†’ Ureter โ†’ Urinary bladder โ†’ Urethra.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
115
Q

What hormones are involved in regulating urine output?

A

Aldosterone and antidiuretic hormone (ADH).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
116
Q

What is glomerular filtration rate (GFR), and why is it significant?

A

GFR is the rate at which the kidneys filter blood, and itโ€™s significant because it reflects kidney function.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
117
Q

What percentage of the total cardiac output do the kidneys receive?

A

20 to 25%.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
118
Q

How much blood do the kidneys process per minute?

A

Approximately 1200 milliliters.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
119
Q

Through which vessels does blood enter and exit the kidneys?

A

Blood enters through the renal artery and exits through the renal vein.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
120
Q

What are the roles of the afferent and efferent arterioles in the nephron?

A

The afferent arteriole brings blood into the glomerulus, and the efferent arteriole carries blood away from the glomerulus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
121
Q

What is the primary function of the glomerular capillaries?

A

To filter blood.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
122
Q

What drives the process of glomerular filtration?

A

High blood pressure within the glomerulus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
123
Q

What are peritubular capillaries, and what is their role?

A

They are low-pressure, porous capillaries closely associated with renal tubules, responsible for absorbing solutes and water from the tubule cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
124
Q

What is the vasa recta, and why is it important?

A

The vasa recta are capillary networks associated with the nephron loops of juxtamedullary nephrons, playing a crucial role in forming concentrated urine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
125
Q

What are the three major processes involved in urine production?

A

Glomerular filtration, tubular reabsorption, and tubular secretion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
126
Q

What substances typically do not pass through the glomerular filtration barrier?

A

Proteins and red blood cells.

127
Q

What is the difference between tubular reabsorption and tubular secretion?

A

Tubular reabsorption involves reabsorbing necessary substances back into the blood, while tubular secretion involves actively adding substances to the filtrate for excretion.

128
Q

What type of process is glomerular filtration?

A

A passive process.

129
Q

What is the main purpose of tubular reabsorption?

A

To reclaim necessary substances from the filtrate back into the bloodstream.

130
Q

How does tubular secretion contribute to urine formation?

A

It actively adds waste and excess substances to the filtrate, which will become urine.

131
Q

How does blood pressure within the glomerulus compare to that within the peritubular capillaries?

A

Blood pressure is high in the glomerulus and low in the peritubular capillaries.

132
Q

What three structures make up the glomerular filtration membrane?

A

Glomerular capillaries, basement membrane, and podocytes.

133
Q

What is unique about the endothelium of glomerular capillaries?

A

It is fenestrated, meaning it has small pores that allow certain substances to pass through.

134
Q

What charge does the basement membrane have, and why is this important?

A

The basement membrane is negatively charged, which helps repel negatively charged particles such as most proteins.

135
Q

What are podocytes, and what role do they play in glomerular filtration?

A

Podocytes are thin epithelial cells with filtration slits that help form the filtration barrier.

136
Q

Which type of molecules can freely pass through the glomerular filtration membrane?

A

Small molecules.

137
Q

What prevents large molecules like red blood cells and large proteins from passing into the glomerular capsule?

A

The size of the filtration membraneโ€™s pores blocks large molecules.

138
Q

Why are most proteins unable to pass through the glomerular filtration membrane?

A

They are large and negatively charged, which causes them to be repelled by the negatively charged basement membrane.

139
Q

What substances are freely filtered into the glomerular capsule?

A

Water, ions, glucose, amino acids, small proteins, vitamins, and nitrogenous waste.

140
Q

Why is glucose filtered into the glomerular capsule, and what must happen to it later?

A

Glucose is small enough to pass through the filtration membrane and needs to be reabsorbed later for energy.

141
Q

What drives the process of glomerular filtration?

A

Hydrostatic pressure (blood pressure).

142
Q

Does glomerular filtration require metabolic energy?

A

No, it relies on positive net filtration pressure.

143
Q

What are the key pressures that influence glomerular filtration?

A

Glomerular hydrostatic pressure, glomerular colloid osmotic pressure, and capsular hydrostatic pressure.

144
Q

Which pressure is the greatest force driving glomerular filtration?

A

Glomerular hydrostatic pressure.

145
Q

How does glomerular colloid osmotic pressure affect filtration?

A

It opposes filtration by pulling water back into the capillaries.

146
Q

What is capsular hydrostatic pressure, and what role does it play in filtration?

A

It is the pressure exerted by the filtrate in the capsular space and opposes filtration.

147
Q

What is net filtration pressure, and why is it important?

A

Net filtration pressure is the sum of glomerular hydrostatic pressure, glomerular colloid osmotic pressure, and capsular hydrostatic pressure. It determines the force driving glomerular filtration.

148
Q

What is the approximate value of net filtration pressure?

A

Approximately 10 mmHg.

149
Q

What does GFR stand for, and what does it measure?

A

GFR stands for Glomerular Filtration Rate and measures the total volume of filtrate formed per minute by all glomeruli in the kidneys.

150
Q

What is the typical GFR in a healthy person?

A

Around 120 milliliters per minute.

151
Q

How many liters of filtrate are produced by the kidneys per day?

A

About 180 liters per day.

152
Q

What factors determine GFR?

A

Net filtration pressure, total surface area available for filtration, and permeability of the filtration membrane.

153
Q

How does a decrease in the number of functioning nephrons affect GFR?

A

It reduces the GFR.

154
Q

What can affect the permeability of the filtration membrane?

A

Drugs, damage from infection, age, or disease.

155
Q

Why is maintaining an adequate GFR essential?

A

It is crucial for efficient waste removal and maintaining homeostasis in the body.

156
Q

Where does tubular reabsorption primarily occur?

A

In the proximal tubule of the renal tubule.

157
Q

How do substances move during tubular reabsorption?

A

Substances move from the lumen of the tubule, through the tubular epithelium and capillary endothelium, back into the blood of the peritubular capillaries.

158
Q

Which substances are commonly reabsorbed during tubular reabsorption?

A

Water, glucose, amino acids, and electrolytes.

159
Q

What role does active transport play in tubular reabsorption?

A

Active transport is used to move sodium ions, the most abundant cations in the filtrate, which also facilitates the secondary active transport of other substances like glucose, amino acids, and some ions and vitamins.

160
Q

What happens to glucose and amino acids during tubular reabsorption?

A

They are usually fully reabsorbed before reaching the nephron loop.

161
Q

Why is the reabsorption of glucose and amino acids important?

A

It is vital for meeting the bodyโ€™s energy needs.

162
Q

How does water move during tubular reabsorption, and what facilitates this movement?

A

Water moves by osmosis into the peritubular capillaries, facilitated by concentration gradients created by sodium and other ions, as well as aquaporins in the proximal tubule.

163
Q

What are transport maximums, and why are they significant?

A

Transport maximums refer to the maximum capacity of specific transport systems for solutes. When transporters are saturated, excess substances are excreted in the urine.

164
Q

How does diabetes mellitus affect glucose reabsorption?

A

In diabetes mellitus, high blood glucose levels can saturate glucose transporters, leading to glucose appearing in the urine, which can cause osmotic diuresis.

165
Q

What is osmotic diuresis, and how is it related to glucose in the filtrate?

A

Osmotic diuresis occurs when glucose in the filtrate draws water with it, leading to the production of large volumes of dilute urine.

166
Q

What is the primary function of the descending limb of the nephron loop?

A

The descending limb primarily reabsorbs water due to the high number of aquaporins.

167
Q

How does the ascending limb of the nephron loop differ from the descending limb in terms of reabsorption?

A

The ascending limb primarily reabsorbs solutes, both actively and passively, and does not couple water reabsorption with solute reabsorption due to fewer aquaporins.

168
Q

Which hormones regulate reabsorption in the distal tubule and collecting duct?

A

Antidiuretic hormone (ADH), aldosterone, and atrial natriuretic peptide (ANP).

169
Q

What effect does antidiuretic hormone (ADH) have on urine production?

A

ADH reduces urine production by promoting water reabsorption into the blood.

170
Q

How does aldosterone influence tubular reabsorption?

A

Aldosterone stimulates the reabsorption of sodium in the distal tubule and collecting duct, leading to increased water reabsorption.

171
Q

What role does atrial natriuretic peptide (ANP) play in tubular reabsorption?

A

ANP inhibits sodium and water reabsorption in the distal tubule and collecting duct, leading to increased urine production.

172
Q

What is the purpose of tubular secretion?

A

To add unwanted substances to the filtrate, which will become urine, and help maintain blood pH and eliminate excess potassium.

173
Q

Where is tubular secretion most prominent?

A

In the proximal tubule of the renal tubule.

174
Q

Which substances are commonly secreted during tubular secretion?

A

Drugs, metabolites, urea, uric acid, creatinine, excess potassium, hydrogen ions, and organic acids and bases.

175
Q

How does tubular secretion help maintain blood pH?

A

By removing hydrogen ions or organic acids and bases from the blood.

176
Q

How is the total volume of urine produced calculated?

A

Urine production = Filtered substances + Secreted substances - Reabsorbed substances.

177
Q

What is the typical daily volume of urine produced in a healthy person?

A

Approximately 1 to 2 liters per day.

178
Q

How much filtrate is typically reabsorbed per day?

A

Approximately 177 to 179 liters per day.

179
Q

What is Glomerular Filtration Rate (GFR)?

A

GFR is the total volume of filtrate formed by all renal nephrons in the kidneys.

180
Q

How many nephrons are typically involved in GFR in a healthy individual?

A

About two million nephrons (one million per kidney).

181
Q

Why is GFR important?

A

GFR is crucial for removing nitrogenous wastes, eliminating excess solutes and water, and maintaining constant blood volume and blood pressure.

182
Q

What balancing act do the kidneys perform in relation to GFR?

A

The kidneys balance waste removal with the regulation of blood volume and pressure, which are potentially opposing requirements.

183
Q

What is the purpose of intrinsic mechanisms in regulating GFR?

A

Intrinsic mechanisms (auto-regulation) maintain a constant GFR despite fluctuations in blood pressure.

184
Q

What is the myogenic mechanism in GFR regulation?

A

The myogenic mechanism involves the contraction and relaxation of vascular smooth muscle in the arterial walls in response to changes in blood pressure.

185
Q

How does the myogenic mechanism respond to increased blood pressure?

A

Increased blood pressure causes the afferent arterioles to constrict, reducing glomerular hydrostatic pressure and GFR.

186
Q

What happens to the afferent arterioles when blood pressure decreases, according to the myogenic mechanism?

A

The afferent arterioles dilate, increasing GFR.

187
Q

What is the tubuloglomerular feedback mechanism?

A

Tubuloglomerular feedback responds to changes in solute concentration in the filtrate and the flow rate through the tubule.

188
Q

How does tubuloglomerular feedback respond to an increase in GFR?

A

High GFR leads to high sodium chloride concentration in the filtrate, detected by macula densa cells, which cause constriction of the afferent arterioles to decrease GFR.

189
Q

What are the two main extrinsic mechanisms that regulate GFR?

A

Neural control and hormonal control.

190
Q

When is neural control of GFR activated?

A

During low extracellular fluid volume or hypovolemic shock.

191
Q

How does neural control affect GFR?

A

Noradrenaline release from sympathetic nerve fibers constricts afferent arterioles, decreasing GFR to maintain vital organ blood supply.

192
Q

What is the function of the Renin-Angiotensin-Aldosterone System (RAAS) in GFR regulation?

A

RAAS maintains blood pressure and indirectly preserves GFR.

193
Q

What triggers the release of renin in the RAAS?

A

Low blood pressure, sympathetic nervous system stimulation, low glomerular hydrostatic pressure, and activation of macula densa cells.

194
Q

What is the role of angiotensin II in GFR regulation?

A

Angiotensin II increases peripheral vascular resistance, raising blood pressure and helping to preserve GFR.

195
Q

What is the overall goal of the regulatory mechanisms of GFR?

A

To maintain homeostasis by ensuring proper filtration, reabsorption, and secretion, thereby preserving fluid balance and cell function.

196
Q

How does the RAAS system indirectly help maintain GFR?

A

By raising blood pressure, the RAAS system helps maintain the hydrostatic pressure necessary for filtration in the glomeruli.

197
Q

What cells detect changes in sodium chloride concentration in the filtrate during tubuloglomerular feedback?

A

Macula densa cells.

198
Q

What are the primary consequences of a decrease in GFR?

A

Reduced waste removal, potential fluid and solute imbalances, and possible increases in blood volume and pressure.

199
Q

Why is maintaining a constant GFR critical for kidney function?

A

A constant GFR ensures efficient waste removal and proper regulation of blood volume and pressure, which are essential for overall homeostasis.

200
Q

What would happen if the kidneys could not regulate GFR effectively?

A

Imbalances in fluid, electrolytes, and blood pressure could occur, leading to potential damage to the kidneys and other organs.

201
Q

What is the role of afferent arterioles in GFR regulation?

A

Afferent arterioles adjust their diameter to either increase or decrease blood flow into the glomerulus, thereby regulating GFR.

202
Q

What happens to GFR during hypovolemic shock?

A

GFR decreases due to the constriction of afferent arterioles, preserving blood flow to vital organs.

203
Q

How does the body ensure that GFR remains within a normal range despite changes in blood pressure?

A

Through intrinsic mechanisms like the myogenic mechanism and tubuloglomerular feedback, and extrinsic mechanisms like neural and hormonal control.

204
Q

What pigment is responsible for the yellow color of urine?

A

Urochrome, a pigment from hemoglobin breakdown.

205
Q

What can cause the color of urine to vary?

A

Diet, metabolism, hydration levels, and certain medical conditions.

206
Q

Describe the typical odor of fresh urine.

A

Fresh urine is slightly aromatic.

207
Q

What can cause urine to develop an ammonia smell over time?

A

Bacterial activity breaking down urea.

208
Q

Name a food that can cause a distinct odor in urine.

A

Asparagus

209
Q

What is the typical pH range of urine?

A

Urine is typically slightly acidic, with a pH range of 4.5 to 8, and an average of around 6.

210
Q

What is specific gravity, and how does it relate to urine?

A

Specific gravity is a measure of urine density compared to water; itโ€™s higher in urine due to the presence of solutes.

211
Q

What percentage of urine is water?

A

Approximately 95%.

212
Q

What are the main solutes found in urine?

A

Sodium, potassium, phosphate, calcium, magnesium, bicarbonate, urea, uric acid, and creatinine.

213
Q

What is urea, and how is it formed?

A

Urea is the major nitrogenous waste in urine, formed from the breakdown of amino acids.

214
Q

What might the presence of blood in urine indicate?

A

Potential issues like damage to glomerular capillaries, trauma, kidney stones, or infections.

215
Q

What could cause urine to appear brown?

A

The presence of bile, which may indicate liver disease or bile duct obstruction.

216
Q

What does the presence of glucose in urine typically indicate?

A

Poorly controlled diabetes mellitus.

217
Q

Why might proteins appear in urine, and what does this suggest?

A

Proteins in urine suggest damage to the filtration membrane in the kidneys.

218
Q

What happens to urine in the collecting ducts?

A

Urine formation is nearly complete, with minimal additional processing occurring.

219
Q

Where does urine go after it leaves the collecting ducts?

A

Urine drains from the collecting ducts into the renal papillae, then into minor calyces.

220
Q

Describe the pathway of urine from the renal pyramid to the ureter.

A

Urine flows from the renal papillae into minor calyces, then into major calyces, and finally collects in the renal pelvis before entering the ureter.

221
Q

What is the function of the ureter?

A

The ureter transports urine from the renal pelvis to the bladder through peristaltic movements.

222
Q

How much urine can the bladder typically store?

A

About 500 mL.

223
Q

What is the difference between the internal and external urethral sphincters?

A

The internal urethral sphincter is under involuntary control (smooth muscle), while the external urethral sphincter is under voluntary control (skeletal muscle).

224
Q

Explain the micturition reflex.

A

The micturition reflex involves the contraction of the detrusor muscle and the opening of the internal and external urethral sphincters, triggered by stretch receptors as the bladder fills.

225
Q

What happens when the external urethral sphincter is voluntarily relaxed?

A

Urination occurs as the sphincter opens, allowing urine to pass from the bladder through the urethra.

226
Q

How does the body prevent involuntary urination when the bladder is full?

A

The external urethral sphincter remains contracted to inhibit urination until voluntary control is exerted.

227
Q

What could lead to involuntary urination despite voluntary effort to hold urine?

A

Increased bladder pressure over time may force the internal urethral sphincter open, leading to involuntary urination.

228
Q

What could cause changes in the pH of urine?

A

Diet and metabolism can alter urine pH, making it more acidic or alkaline.

229
Q

What role does creatinine play in urine, and where does it come from?

A

Creatinine is a nitrogenous waste product derived from muscle activity, excreted in urine.

230
Q

Why might urine be checked for the presence of abnormal constituents like glucose or protein?

A

The presence of these substances can indicate underlying health issues, such as diabetes or kidney damage.

231
Q

What is the role of peristalsis in the ureters?

A

Peristalsis propels urine from the renal pelvis to the bladder.

232
Q

How does the urethra differ in length between males and females?

A

The urethra is longer in males than in females.

233
Q

What happens to urine odor in the case of diabetes mellitus?

A

It may develop a sweet or fruity odor due to the presence of ketones.

234
Q

Through which arteriole does blood enter the glomerulus?

A

The afferent arteriole.

235
Q

Where does the filtration process in the kidney take place?

A

Filtration occurs between the glomerular capillaries and the glomerular capsule.

236
Q

What structures make up the filtration membrane in the glomerulus?

A

The filtration membrane consists of two layers of cells, a basement membrane, fenestrations, and podocyte filtration slits.

237
Q

After the filtrate is formed in the glomerular capsule, where does it go next?

A

The filtrate moves into the proximal tubule.

238
Q

What percentage of water and sodium chloride is reabsorbed in the proximal tubule?

A

About 65% of water and sodium chloride.

239
Q

Name two substances reabsorbed in the proximal tubule besides water and sodium chloride.

A

Glucose and amino acids.

240
Q

What is the main function of secretion in the proximal tubule?

A

Secretion allows certain substances to be added to the filtrate from the blood.

241
Q

In which part of the nephron is approximately 20% of water and sodium chloride reabsorbed?

A

The nephron loop (loop of Henle).

242
Q

What hormone regulates sodium reabsorption and potassium secretion in the distal tubule?

A

Aldosterone

243
Q

What hormone influences water reabsorption in the collecting duct?

A

Antidiuretic hormone (ADH).

244
Q

What is the function of the collecting duct in maintaining blood pH?

A

The collecting duct secretes hydrogen ions and reabsorbs bicarbonate ions to regulate blood pH.

245
Q

At what point in the urine formation process is the filtrate referred to as urine?

A

When it passes through the renal papillae into the minor calyx.

246
Q

Describe the pathway of urine from the renal papillae to the bladder.

A

Urine passes through the minor calyx, major calyx, renal pelvis, and then into the ureters, which propel urine toward the bladder via peristalsis.

247
Q

How does urine move from the renal pelvis to the bladder?

A

It drains into the ureters, which use peristalsis to move it to the bladder.

248
Q

What is the final structure urine passes through before exiting the body?

A

The urethra.

249
Q

What percentage of water can be reabsorbed in the collecting duct under the influence of ADH?

A

Up to 14%.

250
Q

Which ions are involved in the pH regulation function of the collecting duct?

A

Hydrogen ions (H+) and bicarbonate ions (HCO3-).

251
Q

What happens in the glomerulus if the afferent arteriole constricts?

A

Blood flow to the glomerulus decreases, reducing the glomerular filtration rate (GFR).

252
Q

What is the primary role of the nephron loop in urine formation?

A

The nephron loop reabsorbs about 20% of the water and sodium chloride from the filtrate.

253
Q

What role does aldosterone play in potassium balance?

A

Aldosterone regulates potassium levels by promoting either its reabsorption or secretion in the distal tubule.

254
Q

How is glucose normally handled in the nephron?

A

Glucose is reabsorbed in the proximal tubule.

255
Q

What might indicate a problem with the glomerular filtration membrane?

A

The presence of proteins or blood cells in the urine could indicate a problem with the filtration membrane.

256
Q

What structural feature of the ureters helps propel urine to the bladder?

A

The smooth muscle in the ureter walls performs peristalsis.

257
Q

Why is the filtrate called urine only after it reaches the minor calyx?

A

At this point, the filtrate has been fully processed, with reabsorption and secretion completed, making it urine.

258
Q

What is the main function of the proximal tubule?

A

The proximal tubule is responsible for the reabsorption of water, sodium chloride, glucose, amino acids, and other ions, as well as the secretion of waste products into the filtrate.

259
Q

What are short-term controls for blood pressure?

A

Quick adjustments to blood pressure, such as those made when standing up.

260
Q

What are the two mechanisms involved in the renal regulation of blood pressure?

A

Direct renal mechanism and indirect renal mechanism (Renin-Angiotensin-Aldosterone System or RAAS).

260
Q

What happens in the direct renal mechanism when blood pressure is high?

A

Increased blood pressure increases the rate of blood entering the glomerulus, speeding up filtration. This leads to increased urine output, decreased blood volume, and reduced blood pressure.

261
Q

What is the outcome when blood pressure is low in the direct renal mechanism?

A

Low blood pressure slows the rate of blood entering the glomerulus, allowing more time for reabsorption. This reduces urine output, increases blood volume, and raises blood pressure.

262
Q

Why is blood pressure regulation important?

A

To maintain a constant supply of oxygen and nutrients to every cell and to remove waste.

263
Q

What is the main action of aldosterone in blood pressure regulation?

A

Aldosterone increases sodium reabsorption and potassium secretion in the distal tubule and collecting duct, leading to increased water reabsorption, which raises blood volume and blood pressure.

263
Q

List three effects of angiotensin II.

A

Stimulates aldosterone release.
Promotes ADH secretion.
Causes vasoconstriction, increasing total peripheral resistance and blood pressure.

263
Q

What is the role of renin in the RAAS pathway?

A

Renin initiates the RAAS cascade, leading to the formation of angiotensin II.

263
Q

How does ADH affect urine output?

A

ADH increases water reabsorption in the distal tubule and collecting duct by making them more permeable to water, which decreases urine output and increases blood volume and pressure.

264
Q

What triggers the release of renin in the indirect renal mechanism?

A

A decrease in arterial blood pressure.

265
Q

What happens to urine output when aldosterone is released?

A

Urine output decreases due to increased sodium and water reabsorption.

266
Q

How do alcohol and diuretics affect ADH?

A

Alcohol and diuretics inhibit ADH, leading to increased urine production.

267
Q

What overall effect do aldosterone and ADH have on urine output?

A

Both hormones decrease urine output, which increases blood volume and pressure.

268
Q

Describe the sequence of events in the RAAS pathway starting with renin release.

A

Renin is released in response to low blood pressure, which converts angiotensinogen to angiotensin I. Angiotensin I is then converted to angiotensin II, which:

Stimulates aldosterone release.
Promotes ADH secretion.
Activates the thirst center.
Causes vasoconstriction, raising blood pressure.

269
Q

What is the impact of increased water reabsorption by aldosterone and ADH on blood pressure?

A

It leads to increased blood volume, which raises blood pressure.

270
Q

How does the RAAS pathway help in regulating blood pressure over the long term?

A

By increasing blood volume through the reabsorption of water and sodium, the RAAS pathway helps maintain or raise blood pressure over the long term.

271
Q

What role does the thirst center play in blood pressure regulation?

A

Angiotensin II activates the thirst center, leading to increased fluid intake, which helps increase blood volume and pressure.

272
Q

How does vasoconstriction contribute to increased blood pressure?

A

Vasoconstriction caused by angiotensin II increases total peripheral resistance, which raises blood pressure.

273
Q

What effect does aldosterone have on potassium levels?

A

Aldosterone promotes potassium secretion in the distal tubule and collecting duct, lowering blood potassium levels.

274
Q

Summarize the impact of aldosterone and ADH on blood pressure regulation.

A

Aldosterone increases sodium and water reabsorption, while ADH increases water reabsorption. Both actions lead to decreased urine output and increased blood volume, ultimately raising blood pressure.

275
Q

What happens when blood pressure drops significantly?

A

The body acts quickly to restore blood pressure. The kidneys release renin, triggering the RAAS (Renin-Angiotensin-Aldosterone System) cascade to raise blood pressure.

276
Q

How does the RAAS system help restore blood pressure?

A

Renin release starts the RAAS cascade, leading to the formation of angiotensin II. Angiotensin II causes vasoconstriction, stimulates aldosterone and ADH release, and activates the thirst center, all of which help raise blood pressure.

277
Q

What are the primary functions of the urinary system?

A

Urine production to maintain blood pressure and remove waste.
Excretion of metabolic wastes and foreign substances.
Regulation of acid-base balance.
Regulation of erythropoiesis (red blood cell production).
Activation of vitamin D.
Gluconeogenesis.

278
Q

How does the urinary system activate vitamin D?

A

The kidneys convert inactive vitamin D into its active form, which is necessary for calcium absorption and bone health.

279
Q

What is gluconeogenesis and how is it related to the urinary system?

A

Gluconeogenesis is the production of glucose from non-carbohydrate sources during fasting or starvation. The kidneys contribute to this process.

280
Q

Which of the following is NOT a main function of the urinary system?

A) Regulation of blood pressure
B) Regulation of erythropoiesis
C) Production of digestive enzymes
D) Excretion of metabolic wastes

A

C) Production of digestive enzymes

281
Q

What structure within the nephron is primarily responsible for filtration?

A) Proximal convoluted tubule
B) Glomerulus
C) Loop of Henle
D) Distal convoluted tubule

A

B) Glomerulus

282
Q

Which part of the kidney contains the renal pyramids?

A) Renal cortex
B) Renal medulla
C) Renal pelvis
D) Renal capsule

A

B) Renal medulla

283
Q

The main structural and functional unit of the kidney is the:

A) Nephron
B) Ureter
C) Glomerulus
D) Renal pelvis

A

A) Nephron

284
Q

Which structure collects urine directly from the renal papillae?

A) Minor calyx
B) Major calyx
C) Renal pelvis
D) Ureter

A

A) Minor calyx

285
Q

Glomerular filtration occurs in which part of the nephron?

A) Distal convoluted tubule
B) Proximal convoluted tubule
C) Glomerulus
D) Loop of Henle

A

C) Glomerulus

286
Q

What is the primary force driving glomerular filtration?

A) Secretion in the distal tubule
B) Oncotic pressure in the Bowmanโ€™s capsule
C) Tubular reabsorption
D) Hydrostatic pressure in the glomerular capillaries

A

D) Hydrostatic pressure in the glomerular capillaries

287
Q

What is the normal range for glomerular filtration rate (GFR) in a healthy adult?

A) 60-90 mL/min
B) 90-120 mL/min
C) 120-150 mL/min
D) 150-180 mL/min

A

B) 90-120 mL/min

288
Q

Which of the following can cause a decrease in GFR?

A) Increased blood pressure
B) Constriction of the afferent arteriole
C) Dilation of the afferent arteriole
D) Increased glomerular hydrostatic pressure

A

B) Constriction of the afferent arteriole

289
Q

What percentage of plasma entering the glomerulus is typically filtered into the Bowmanโ€™s capsule?

A) 10%
B) 50%
C) 30%
D) 20%

A

D) 20%

290
Q

Where does the majority of tubular reabsorption occur?

A) Distal convoluted tubule
B) Loop of Henle
C) Proximal convoluted tubule
D) Collecting duct

A

C) Proximal convoluted tubule

291
Q

Which of the following substances is typically secreted into the tubule?

A) Glucose
B) Sodium
C) Hydrogen ions
D) Water

A

C) Hydrogen ions

292
Q

What percentage of sodium is reabsorbed in the proximal convoluted tubule?

A) 25%
B) 50%
C) 65%
D) 90%

A

C) 65%

293
Q

Which part of the nephron is primarily responsible for creating the osmotic gradient in the kidney?

A) Proximal convoluted tubule
B) Loop of Henle
C) Distal convoluted tubule
D) Collecting duct

A

B) Loop of Henle

294
Q

Tubular secretion is important for all the following EXCEPT:

A) Eliminating waste products
B) Regulating blood pH
C) Reabsorbing nutrients
D) Removing excess potassium

A

C) Reabsorbing nutrients

295
Q

Which mechanism directly affects the glomerular filtration rate (GFR)?

A) Tubuloglomerular feedback
B) Myogenic response
C) RAAS activation
D) All of the above

A

D) All of the above

296
Q

How does the constriction of the efferent arteriole affect GFR?

A) Decreases GFR
B) Increases GFR
C) Has no effect on GFR
D) Increases urine output

A

B) Increases GFR

297
Q

The macula densa cells respond to changes in:

A) Blood pressure
B) Sodium concentration in the distal tubule
C) Blood glucose levels
D) Potassium concentration in the blood

A

B) Sodium concentration in the distal tubule

298
Q

What effect does a high GFR have on the rate of filtrate reabsorption?

A) Increases reabsorption
B) Decreases reabsorption
C) Has no effect on reabsorption
D) Stops reabsorption altogether

A

B) Decreases reabsorption

299
Q

Which of the following hormones is involved in the regulation of GFR?

A) Renin
B) Insulin
C) Glucagon
D) Thyroxine

A

A) Renin

300
Q

What is the typical color of healthy urine?

A) Clear
B) Pale yellow
C) Dark brown
D) Red

A

B) Pale yellow

301
Q

Which of the following structures does urine pass through immediately after the collecting ducts?

A) Renal pelvis
B) Minor calyx
C) Major calyx
D) Ureter

A

B) Minor calyx

302
Q

Which structure stores urine until it is excreted?

A) Urethra
B) Ureter
C) Bladder
D) Renal pelvis

A

C) Bladder

303
Q

What is the normal pH range of urine?

A) 3.0-4.5
B) 4.5-8.0
C) 7.0-9.5
D) 8.0-10.5

A

B) 4.5-8.0

304
Q

Which structure serves as the final passage for urine to leave the body?

A) Collecting duct
B) Ureter
C) Renal pelvis
D) Urethra

A

D) Urethra

305
Q

Which hormone increases sodium reabsorption in the distal convoluted tubule and collecting duct?

A) ADH
B) Aldosterone
C) Renin
D) Insulin

A

B) Aldosterone

306
Q

What triggers the release of antidiuretic hormone (ADH)?

A) High blood pressure
B) Low blood osmolarity
C) High blood osmolarity
D) High blood glucose

A

C) High blood osmolarity

307
Q

Which hormone directly causes vasoconstriction to increase blood pressure?

A) Angiotensin II
B) Aldosterone
C) ADH
D) Renin

A

A) Angiotensin II

308
Q

What is the effect of alcohol on ADH secretion?

A) Increases ADH secretion
B) Decreases ADH secretion
C) Has no effect on ADH
D) Inhibits aldosterone secretion

A

B) Decreases ADH secretion

309
Q

Aldosterone has the greatest effect on which of the following?

A) Potassium excretion
B) Glucose absorption
C) Calcium reabsorption
D) Blood glucose levels

A

A) Potassium excretion