31 :D

Question 1

Why do we need kidneys?

Answer 1

To control WHAT is in our blood and HOW MUCH blood we have

Question 2

Major functions of the kidney

Answer 2

To control WHAT is in our blood and HOW MUCH blood we have

Question 3

Endocrine function of the kidney

Answer 3

➤ low blood oxygen levels are detected by the kidneys
➤ the kidneys release EPO
➤ EPO stimulates the bone marrow to produce more red blood cells

Question 4

What happens when Chronic kidney/renal failure

Answer 4

➤ the kidneys cannot make enough EPO
➤ reduced red blood cell production
➤ ANAEMIA: low blood oxygen levels (dont have enough haemoglobin)

Question 5

Function of the kidney - metabolic: gluconeogenesis

Answer 5

During fasting, or when our body is under stress:
- The kidneys make glucose (from lactate)

Question 6

What is ph?

Answer 6

pH is a measure of how acidic or alkaline a solution is:
- pH = -log[H+]
- pH is the inverse (opposite) of H+ ion concentration

Question 7

The more _____ ions there are the lower the _____
= more _____

Answer 7

The more H+ ions there are the lower the pH
= more acidic

Question 8

The _______ H+ ions there are the _________ the pH
= more basic/alkaline

Answer 8

The fewer H+ ions there are the higher the pH
= more basic/alkaline

Question 9

What happens when pH is not regulated tightly?

Answer 9

Acidosis vs alkalosis
- urine has a wider pH range as it allows us to pee out the extra acid or extra base

Question 10

Two main sources of acid in the body:

Answer 10

• Acids coming from metabolism, food and drink
  • direct sources of H+ (Non-volatile acids)
• Carbon dioxide from metabolism
• more carbon dioxide you have the more you will shift the below equilibrium thus making more H+

Question 11

Two systems The pH of the blood is controlled by:

Answer 11

• Lungs: exhalation of carbon dioxide (CO2)
• Kidneys: by reabsorption and secretion of bicarbonate (HCO3-) and hydrogen ions (H+)

Question 12

Function of the kidney - Salt/ion homeostasis: what is it important for?

Answer 12

Potassium (K+) concentration is vital for many processes!!

Importance in all cells: the resting membrane potential is based on K+ gradient (inside/outside) of cell

Neurons and cardiomyocytes: APS, rhythm generation is pacemaker cells, contractiltiy, signalling

Question 13

Too much potassium =

Answer 13

Death❌

Question 14

In terms of ion homeostasis, what happens if the kidneys stop working?

Answer 14

hyperkalemia (death) - too much potassium

Question 15

Major functions of the kidney: excretion of medications - which two in particular?

Answer 15

• Lidocaine is a commonly used local anaesthetic
  
  • excreted by the kidneys AFTER metabolism in the liver due
    to its fat soluble (lipophilic) nature (travel bound to a
    protein which is too big to be filtered so goes via the liver
    to be metabolised and be able to travel in the blood)
• Aspirin is a common pain killer
  
  • excreted directly by the kidneys due to its high water
    solubility (hydrophilic)
• medications are filtered and secreted by the kidneys to be excreted from the body in the urine

Question 16

Major functions of the kidney: Body water balance

Answer 16

• Total body water remains relatively constant
• Intake and loss of water must balance
• Urine output is adjusted to maintain balance

Question 17

Answer 17

Question 18

Practice calculating

Answer 18

Question 19

Volume of fluid in the body water compartments can change due to:

Answer 19

• how much water there is in the body
• the osmolarity of the body water compartments (water moves to where the osmolarity is the highest)

Question 20

Why does it matter how much water there is in our body?

Answer 20

Increase in plasma = increase in BP
Decrease in plasma = decrease in BP
Increase in ICF = swelling of cells
Decrease in ICF = shrinking of cells

Question 21

What is Osmolarity

Answer 21

The total number of solute molecules in a solution

Question 22

Normal osmolarity:

Answer 22

Extracellular fluid (including plasma):
- 275-300 mosmol/L

Intracellular fluid:
- 275-300 mosmol/L

Question 23

What does Isosmotic mean?

Answer 23

• same amount of solute molecules per litre
• same osmolarity

Question 24

A change in the amount of ____ in the _____ changes the ______

Answer 24

A change in the amount of water in the ECF changes the osmolarity

Question 25

How A change in the amount of water in the ECF changes the osmolarity

Answer 25

Question 26

Change in osmolarity - loss or gain in water

Answer 26

Water goes to to ECF / leaves the ECF first as it is the transitional compartment

Question 27

Change in volume

Answer 27

- only goes to or comes from your extracellular fluid

Question 28

If you drink 1 L of isosmotic fluid the volume of your extracellular fluid (ECF) will increase by: A. 0 L B. 0.33 L C. 0.66 L D. 1 L

Answer 28

D

Question 29

Basic functions of the nephron

Answer 29

1. Filtration 2. Secretion 3. Reabsorption

Question 30

Basic nephron functions - filtration

Answer 30

- Occurs in the renal corpuscle/ glomerulus - Movement of plasma from the glomerular capillaries (blood) into the glomerular capsule Most substances in plasma are freely-filtered - Exception: large proteins (e.g. albumin) and substances bound to proteins - Water and solutes are filtered at a constant rate at the renal corpuscle (glomerulus) Creates a plasma-like filtrate of the blood (pretty much just plasma without the large proteins)

Question 31

Basic nephron functions - secretion

Answer 31

Movement of solutes from the peritubular capillaries (blood) into the tubular fluid Removes additional substances (waste products) from the blood by secreting them into the tubular fluid so they are excreted in the urine - E.g. metabolites, medications and toxins THIS MAINLY HAPPENS IN THE PROXIMAL TUBULE

Question 32

Basic nephron functions - reabsorbtion

Answer 32

- Movement of solutes from the tubular fluid into the peritubular capillaries (blood) - Returns useful substances to the blood so they are NOT excreted in the urine

Question 33

Proximal tubule: absorbtion?

Answer 33

- Bulk reabsorption of ions (sodium), water and nutrients (glucose)

Question 34

Nephron loop: absorbtion?

Answer 34

Bulk reabsorption of ions (sodium), water

Question 35

Distal tubule and collecting duct: absorbtion?

Answer 35

Fine-tuning reabsorption of ions (sodium) and water

Question 36

All 3 basic functions of the nephron

Answer 36

Filtration: - Creates a plasma-like filtrate of the blood - Blood → Nephron Secretion: - Removes additional substances (waste products) from the blood and adds them into the tubular fluid - Blood → Nephron Reabsorption: - Returns useful substances to the blood by removing them from the tubular fluid - Nephron → Blood The balance of these processes determines the way a particular substance is handled in the kidneys.

Question 37

Major functions of each part of the nephron - glomerus

Answer 37

Filtration of plasma

Question 38

Major functions of each part of the nephron - proximal tubule

Answer 38

- Secretion of metabolites, medications and toxins - Bulk reabsorption of ions (sodium), water and nutrients (glucose)

Question 39

Major functions of each part of the nephron - nephron loop

Answer 39

Bulk reabsorption of ions (sodium), water

Question 40

Major functions of each part of the nephron - Distal tubule and collecting duct:

Answer 40

Fine-tuning/regulated (by hormones) reabsorption of ions (sodium) and water

Question 41

Answer 41

- Different substances are handled differently in different parts of the nephron - The balance of these processes determines the way a particular substance is handled in the kidneys

Question 42

Sodium filtration

Answer 42

Question 43

Glucose filtration

Answer 43

Question 44

PAH filtration

Answer 44

Question 45

Filtration of creatinine and insulin

Answer 45