Kidney Physiology and Function Flashcards
What are the 3 main functions of the urinary system?
1) Excretion
2) Elimination
3) Regulation
Explain what excretion means in terms of the kidney.
Removal of organic waste products from body fluids.
IE: Ammonia // Uric // Amino acids.
IE: Creatinine.
Explain what elimination means in terms of the kidney.
Discharge of waste products from the body.
Explain what regulation means in terms of the kidney.
Homeostatic regulation of volume and solute concentration of blood plasma.
What are the 3 main parts of the kidney?
Renal Cortex
Renal Medulla
Renal Pelvis
What composed together creates the renal lobes?
Renal pyramids + “outer” renal cortex.
What is the renal medulla?
This is where the nephrons are located and consists of 6 - 18 structures known as ‘renal pyramids’.
What is the purpose of the renal lobes?
This is the site of urine production and the urine drains into the calyx.
In terms of blood supply, how much of the cardiac output does kidneys receive?
20 - 25%.
How is blood pressure maintained ini the kidneys?
There is a network of capillaries which gets smaller ini size and thus maintains the blood pressure.
Where is blood pressure the highest?
In the glomerulus.
Give the journey of blood through the kidney starting at the aorta and ending at the vena cava.
From aorta to renal artery to the kidney.
ENTERS THE GLOMERULUS IN THE BOWMANS CAPSULE.
From the kidney to the renal vein to then vena cava.
Which nervous system is associated with the nervous control of the kidneys?
Sympathetic Nervous System.
Where are the renal sensory nerves usually found?
In the renal pelvic wall.
What does the sympathetic nervous system control?
Controls the juxtaglomerular cells alongside the renal tubules and vasculature (known as the vascular system of the body).
What is hypertension?
High blood pressure and increased risk of heart disease.
What is the purpose of the adrenal glands?
These are important for the production of hormones which can regulate the renal function.
What are the 2 main glands?
Adrenal Cortex
Adrenal Medulla
Which gland produces the ESSENTIAL hormones?
Adrenal Cortex
What are the essential hormones produced?
Cortisol = Regulates metabolism Aldosterone = Controls blood pressure
Which gland produces the NON - ESSENTIAL hormones?
Adrenal Medulla
What are the non - essential hormones produced?
Adrenaline = Reacts to stress levels
What is another name for aldosterone?
Mineralocorticoids.
Which types of nephrons are there?
85% = Cortical Nephrons 15% = Juxtamedullary Nephrons
What is the difference between cortical and juxtamedullary nephrons?
Cortical has the glomerulus near the outer parts of the cortex.
Has a SHORT Loop of Henle.
Juxtamedullary has the glomerulus near the junction of the cortex and the medulla.
Has a LONG Loop of Henle.
What is the purpose of the nephrons?
Functional unit of the kidney which regulates water and soluble substances = Filters the blood and reabsorbs what is needed. The rest is excreted as urine.
What is the structure of the nephron?
Renal Corpuscle
Renal Tubule
Collecting System
What makes up the renal corpuscle?
Bowman’s Capsule
Glomerulus
Glomerular Capillary Network
What makes up the renal tubule?
Proximal convoluted tubule.
Loop of Henle
Distal convoluted tubule
What is part of the collecting system?
Collecting Duct.
How is blood supplied to the nephron?
Blood ARRIVES at the nephron from the AFFERENT arteriole.
Enters the glomerular capillaries.
Blood EXITS the nephron from the EFFERENT arteriole.
What is an arteriole?
Single celled vessels which allow efficient gas exchange.