Renal Physiology Flashcards
Another name for Anti-Diuretic Hormone is?
Vasopressin
Water in the body is gotten through 2 ways?
- Water ingested
- Water synthesized by the body
Oxidation of carbohydrates is the basis for synthesis of?
Water in the body
The approximate amount of water taken in to the body is?
2100ml/day
The approximate amount of water synthesized in the body is?
2300ml/day
The water lost unconsciously from the body through evaporation from respiratory tract or diffusion through skin is known as
Insensible water loss
The total insensible water loss from the body is approximately?
700ml/day
The amount of water lost through evaporation from the respiratory tract measures to?
300-400 ml/day
Insensible water loss in the skin is minimised by what layer of the skin?
Cholesterol filled Cornified layer of the skin
When Cornified layer is denuded, the rate of evaporation can increase to what amount per day?
3-5L per day
The normal volume is sweat daily is?
100ml
In very hot weather or during heavy exercise, volume of sweat may increase to ?
1-2 Litres per hour
When body fluid is depleted due to sweating, thirst is activated..
True/False
True
100ml of water is lost in faeces..
True/False
True
There are 2 body fluid compartments, name them?
- Extracellular fluid (ECF)
- Intracellular fluid (ICF)
ECF is divided into 3, name them ?
- Interstitial fluid
- Blood plasma
- Transcellular fluid
Synovial fluids, peritoneal fluids, pericardial fluid, intraocular fluid are all known as?
Transcellular fluid
In an average 70kg adult, total body water takes what percentage and volume?
60% of body weight
Volume = 42L
Men normally have more percentage of water than women, this is because?
Women have more body fats than men
The volume and percentage of intracellular fluid in the body is?
28Litres, which is 40% of body weight
Extracellular fluid accounts for what volume and percentage of body weight?
14Litres
20% of body weight
60% of the blood is composed of?
Plasma
40% of blood is composed of?
Erythrocyte
The fraction of blood composed of RBC is called?
Hematocrit
What is polycythemia?
Polycythemia is the excessive production of RBC
Fluid in body compartments is measured using what principle?
Indicator-dilution principle
Antipyrine is a substance used to measure ?
Body fluid volume using dilution principle
Intracellular volume is calculation by
ICF = total body water - ECF volume
A common substances used in measuring plasma include?
- Serum albumin labelled with radioactive (125- albumin)
- Evans blue dye
Interstitial fluid is calculated by
Extracellular fluid volume - Plasma volume
The osmolal concentration of a solution is known as ?
Osmolality
When the osmolal concentration is expressed as osmoles per litre of solution, it is called?
Osmolarity
The movement of molecules of a liquid or gas through a semi permeable membrane, is called
Osmosis
The force that prevents osmosis is called?
Osmotic pressure
Higher the osmotic pressure = lower water concentration and Higher concentration of solution.
True or false?
True
The presence of excess fluid in the body tissues is simply called
Edema
The force exerted by a fluid against the wall of a vessel is called?
Hydrostatic pressure
Surplus fluid in the interstitial space that is not directly returned to the capillaries is drained by what body system?
The lymphatic system
Excess Fluid drained by the lymphatic system from tissues re-enters the vascular system through what vein?
The subclavian vein
There are 2 types of edema, namely?
- Intracellular edema
- Extracellular edema
Mathematically, capillary filtration rate is calculated by?
Capillary filtration coefficient (kF) ÷ by capillary hydrostatic pressure - Plasma colloid pressure (pC) + interstitial fluid hydrostatic pressure (PiF)
Glucose molecules move down the concentration gradient through?
Facilitated diffusion
Proteoglycan filament
Increased lymph flow and
washdown of interstitial fluid protein
All act as safety factors against?
Edema
Mention the potential spaces for fluid in the body
- Pleural cavity
- Pericardial cavity
- Peritoneal cavity
- Synovial cavity
- Bursae
- Joints
After age 40, what happens to the number of functional nephrons?
The number decreases about 10% every 10years
The glomerulus has a basement membrane which contain?
- Laminins
- Type IV collagen
- Agrin
- Nidogen
The visceral epithelium of the kidney is called?
Podocytes
The GFR makes up what percentage of renal plasma flow?
20%
Net filtration pressure (10mmhg) is gotten by?
Glomerular hydrostatic pressure(60mmhg) - Bowman’s capsule pressure (18mmhg) - Glomerular oncotic pressure (32mmhg)
Mathematically GFR is equal to?
Capillary filtration coefficient × Net filtration pressure
The net filtration pressure is?
The sum of hydrostatic forces and osmotic forces
Osmotic forces oppose fluid filtration?
True or false
True
Hydrostatic forces favour fluid filtration.
True or false
True
Increased hydrostatic pressure in Bowman’s capsule decreases GFR.
True or false
True
Precipitation of Calcium or uric acid can lead to?
Formation of stones that lodge in the urinary tract
Kidney stones can damage or destroy the kidney .
True or false
True
Increased glomerular capillary colloid osmotic pressure leads to?
Decrease in GFR
Increased blood flow into glomerulus causes?
Increase in GFR
Reduced blood flow into the glomerulus decreases GFR.
True or false
True
Nephrons have similar component, but differ depending on how deep they lie within the kidney.
True or false
True
Nephrons that lie in the cortex are called?
Cortical nephrons
Nephrons that have glomeruli that lie deep in the renal cortex near the Medulla are known as?
Juxtamedullary nephrons
The entire tubular system in cortical nephrons are surrounded by?
Peritubular capillaries
In Juxtamedullary nephrons, long efferent arterioles divide into specialised peritubular capillaries called?
Vasa recta
Vasa recta empty into?
Cortical veins
The Vasa recta plays an essential role in?
The formation of concentrated urine
What is the function of renal tubular epithelial cells?
They convert 180L of glomerular filtrate into 1-2L of urine
Mention the general factors influencing tubular transport of substances
- Transporters
- Endocytic receptors
- Epithelial cell polarity
- Specialised properties of renal epithelial cells
There are 3 types of tubular transporters, name them
- Uniporter
- Co-transporter or symporter
- Antiporter or exchanger
The proximal tubule absorbs How many percent of glomerular filtrate?
60%
Example of major solutes reabsorbed by the proximal tubule include?
- Potassium
- Chloride
- Bicarbonate
- Sulphate
- Citrate
- Phosphate
- Calcium
- Glucose
- Uric acid
The proximal tubule also has secretory functions.
True or false
True
The proximal tubule secretes?
- Oxylate
- Toxins
- Organic anions and cations
- Sodium
A clinical application of Dysfunction of the proximal tubule is?
Fanconi’s syndrome
Reabsorption takes place in the proximal tubule.
True or false
True
Symptoms of fanconi’s syndrome include;
- Glucosuria
- Hypophosphatemia
- Polyuria
- Absence of azotemia
- Proximal renal tubular acidosis
- Aminoaciduria and proteinuria
Heat production in the body is due to?
Oxidation of food molecules
When the rate of heat produced equals the rate of heat lost, it is known as?
Thermal equilibrium
Thermostatic activities in the body are regulated by?
The Hypothalamus
