Renal Flashcards
What are the basic components of the Urinary system?
- Kidneys
- Uterers
- Bladder
- Urethra
What is the function of the uterers?
Move the urine from the kidneys to the bladder
What is peristalsis?
It is the symetrical contraction of muscle and is a primary method of transportation of urine from the kidneys to the bladder.
How much liquid can the bladder hold?
400 - 600 mL
When does the bladder signal to void the liquid stored?
At 75%
What is the function of ureter?
Movement of urine from the bladder out of the body
Describe the process of urine removal from the bladder.
- Stretch of the bladder stimulates the PNS to contract smooth muscle and relax the internal urethral sphincter
- After the voluntary controlled external urethral sphincter is relaxed
- Urine exits the urethra
What are the three zonas of the adrenal gland cortex?
- Zona glomerulosa
- Zona fasciulata
- Zona reticularis
What hormones are secreted by the first zona of the adrenal gland cortex?
Zona glomerulosa - aldosterone
What hormones are secreted by the second zona of the adrenal gland cortex?
Zona fasciulata - cortisol
What hormones are secreted by the third zona of the adrenal gland cortex?
Zona reticularis - sex hormones
What hormones are secreted by the medula of the adrenal glands?
Catecholamines - adrenaline & noradrenaline
What are the four main homeostatic functions that are performed by the kidneys?
- Salt and water regulation
- Acid regulation
- Blood pressure regulation
- Removal of by-products, toxins, drugs
What can we consider kidney as?
Kidney can be considered as:
- Major organ that helps to control whole body homeostasis
- An endocrine gland
What are some of the endocrine functions of the kidneys?
- Renin production
- Erythropoietin (EPO) production
- VItamin D activation/deactivation
Show all elements of the diagram
What are nephrons?
Nephrons are functional components of kidneys.
What are the functions of nephrons?
- Filtration of plasma
- Concentrating urine
- Removal of toxins and by-products
What are the two components of a nephron?
- Tubular
- Vascular
Show all elements of the following diagram
What are the two main types of nephrons?
- Juxtamedullary
- Cortical
What are the more common type of nephron?
Cortical is more common than juxtamedullary
What is the difference in the loop on Henle in the two nephrons?
Juxtamedullary nephrones have long loops of henle while cortical have short once.
What is the difference in the vascular structure between juxtamedullary and cortical nephrons?
Juxtamedullary have a vasa recta structure - meaning straight blood vessels. Cortical have a meshed structure.
What is the glomerulus?
It is the functional unit of filtration
What is the result of high pressure in arterioles?
Ultrafiltration
Which blood vessel of the glomerulus is larger?
The afferent artriole is larger than the efferent artriole
What is the function of smooth muscle within the arterioles?
They are able to regulate blood pressure with greater control
How does the filtrate move through the glomerulus?
- In capilaries
- Through the bowman’s capsule
- Into the proximal tubule for further prosessing
Which 2 structures are technically fuzed together in the juxtaglomerular aparatus?
The afferent arteriole and the distal tubule
What are the juxtaglomerular granular cells, what is their location and function?
- Granular cells are specialised smooth muscle cells
- Found primarily on the afferent arteriole
- Function: synthesise, store and secrete renin
What is the process of renin release and what does it influence?
- Renin is released by the granulwar cells in response to: low blood pressure, low NaCl in tubules via macula densa cells and sympathetic nervous drive
- Renin is used in the RAAS system
What are the three main functions of the nephron?
- Glomerular filtration
- Tubular secretion
- Tubular resorbtion
How do capilary blood vessels facilitate the movement of substances in the glomerulus?
- Blood vessels are fenestrated
- Fenestrations allow the pessage of some waste products but not whole cells
- They move according to concentration gradients
What are the three layes of the glomerular barrier that facilitate filtration?
- Lumen of the capilaries
- Basement membrane
- Lumen of Bowman’s capsule
What is the glomerular filtration rate?
It is the rate of filtered fluid through both kidneys per minute. It is a measure of total kidney function. Normal 125 ml/min
How can we calculate the GFR?
By using substances that can be freely filtered and not at all resorbed. SUch substance is creatinine - a bi-product of muscle metabolism.
What s the formula for GFR?
GFR = (urine concentraion x urine flow)/plasma concentration