Anatomy & Physiology of the Renal Systems

Question 1

Describe the 6 parts of the nephron that liquid moves through

Answer 1

1. Bowmans Capsule/ Glomerulus
2. Proximal Tubule
3. Descending Loop of Henle
4. Ascending Loop of Henle
5. Distal Tubule
6. Collecting Duct

Question 2

Identify the functions at each of the 6 parts of the Nephron

6 Parts= Bowmans capsule/glomerulus, proximal convoluted tubule, descending loop of henle, ascending loop of henle, distal convoluted tubule

Answer 2

1- Bowmans Capsule/Glomerulus- Filters out small solutes from the blood such as water, glucose, amino acids, sodium, chloride, potassium, and waste products like creatinine & urea. (blood enters glomerulus via afferent arteriole & exits via the efferent arteriole)

Question 3

Describe the difference between the:

Afferent Arteriole & Efferent Arteriole

(compare- if blood enters or exits through this vessel, its length, width, level of resistance & whether solutes move through osmotic or hydrostatic pressure)

Answer 3

Afferent Arteriole= Blood enters glomerulus via afferent arteriole. It is short, wide & low resistance. Solutes move OUT through hydrostatic pressure

Efferent Arteriole= Blood exits glomerulus via efferent arteriole. It is long, narrow & high resistance. Solutes move IN via osmotic pressure

Question 4

What are some key functions of the kidneys?

(think of the key functions of the nephrons)

Answer 4

Regulates ions in blood (nephrons move sodium, chloride, glucose, amino acids, potassium etc. IN and OUT of the blood)

Regulates blood pH

Regulates BP (by shifting how much sodium & water is reabsorbed & secreted)

Excretes wastes & toxins (nephrons remove them from the blood and excrete them through urine)

Regulation of BGL (nephrons can excrete excess glucose)

Question 5

Describe the steps of the Renin Angiotensin Aldosterone System

Answer 5

1. LOW Blood Pressure

2. Renin secreted by Kidney

3. Renin converts angiotensinogen (from liver) into angiotensinogen I

4. ACE-angiotensin-converting enzyme (from lungs) converts angiotensinogen I to angiotensinogen II

5. Angiotensinogen II then:

5a) Stimulates a neural response (vasoconstriction, ADH release, stimulate thirst)
5b) stimulates adrenal cortex to release aldosterone- aldosterone increases sodium permeability of DCT & collecting ducts. Sodium reabsorption increases. This creates an osmotic pressure so water reabsorption also increases (water follows the sodium)

= Increased water reabsorption increases blood volume

= ­Increased Blood Pressure

Question 6

What are the 3 types of processes that control Glomerular Filtration (& work to increase BP)

[no need to explain each for this flashcard]

Answer 6

PROCESSES THAT CONTROL GFR & BP

1. Autoregulation (modification of blood vessel resistance)
2. Hormonal (RAAS)
3. Autonomic/Neural (Sympathetic NS)

Question 7

There are 3 processes which control Glomerular Filtration & maintain blood pressure. One of those is AUTOREGULATORY processess. Explain this process

Answer 7

GFR & BP can be altered through- AUTOREGULATION PROCESSESS:

What is this? This is your kidneys ability to alter their own resistance of their blood vessels (afferent & efferent arterioles in the nephron) to maintain blood flow through the glomerulus.

When your BP drops: Afferent dilates, Efferent constricts= increased blood flow to glomerulus

Question 8

There are 3 processes which control Glomerular Filtration & maintain blood pressure. One of those is the HORMONAL process. What is the Hormonal Process the kidneys facilitate?

Answer 8

GFR & BP can be altered through- HORMONAL PROCESSES:

This refers to the RAAS (Renin Angiotensin Aldosterone System) which can increase blood pressure

Question 9

There are 3 processes which control Glomerular Filtration & maintain blood pressure. One of those is the NEURAL/AUTONOMIC process. What are the neural/autonomic processes that can increase BP?

Answer 9

GFR & BP can be maintained through- NEURAL/AUTONOMIC processess. This refers to the sympathetic nervous system being able to help increase BP. For example though:

Increasing vasoconstriction

Increasing HR

Stimulating the release of ADH from the adrenal cortex

Increasing thirst

Question 10

Aldosterone and ADH (Anti-diuretic Hormone) both work on parts of the nephron to increase blood pressure. Which part of the nephron does each hormone target, and what do they do?

Answer 10

Aldosterone and ADH (Anti-diuretic Hormone) both work on the nephron to increase blood pressure, however:

ALDOSTERONE- increases water reabsorption/ uptake indirectly. It increases permeability of sodium in the Distal Convoluted Tubule (DCT), which creates an osmotic pressure that then draws water out

ADH- increases water reabsorption/uptake directly. It increases permeability of water in the collecting ducts