Lecture 2 - Structure Flashcards
What is the name used for peeing
Micturition
What does the urinary tract consist of
Kidneys
Ureters
Urinary bladder
Urethra
How big are the kidneys
4-5” long
2-3” wide
1” thick
What protects the kidneys
11-12th ribs
Where do the blood vessels and the ureter enter
The hilus of the kidneys
What does the renal capsule do
Maintains the kidneys shape
What does the adipose capsule do
Protects the kidney from any trauma
What does the renal fascia do
Holds the kidneys against the back body wall
What does the kidneys consist of
Cortex Medulla Pyramids Papillae Columns Calyces Pelvises
What is the kidneys functional unit
Nephron
How many functional units does the kidney have
1 million
What does the glomerulus do
Filters the blood and stops protein and blood entering urine
What part forms urine
Glomerular filtrate
What does the tubule do
Re absorbs an secretes fluids and electrolytes to adjust urine composition and maintain body fluid homeostasis
What does a nephron consist of
Corpuscle - fluid is filtered
and a
Tubule - where filtered fluid passes
What are the 3 functions of the nephron
Glomerular filtration
Re absorption
Tubular secretion
What does a tubule consist of
PCT
Loop of henle
DCT
Papillary ducts
DCT
Collecting duct
Put it in order In which they drain into
DCT drain into the collecting ducts.
Collecting ducts drain into papillary ducts
What does the loop of henle consist of
Descending limb
Think ascending limb
Thick ascending limb
How many types of nephrons are there
2 types
Cortical nephron
Juxtamedullary nephron
What is the major difference in the cortical nephrons and the juxtamedullary nephrons
Cortical nephron has a short loop of henle and the juxtamedullary nephron has a long loop of henle
What is the bowmans capsule
Network of capillaries in the glomerulus
What artery supplies the kidney
Renal artery
How much does the artery divide into for each kidney
5 segments
The neurological supply to the kidneys is involved with what
Regulation of Vasomotor tone
Where do sympathetic fibres originate
In the lower splanchnic nerves that travel through the lumbar ganglia to the kidney
Where else are the sympathetic fibres said to originate from
Thoracic area travelling from the kidney via coeliac ganglion
What does stimulation of the sympathetic nervous system do
Enhances sodium respiration
Where do the parasympathetic fibres arose
In 2nd and 4th sacral nerve roots
S2 and S4 what is their function
Bladder emptying
Penile erection
Sympathetic T11-L3 what is the function
Reduces bladder tone and inhibits parasympathetic system
What fibres are linked to the base of the bladder and proximal urethra
Sympathetic fibres
The sympathetic fibres in the bladder what do they do
Facilitate closure of the bladder neck and the urethral sphincter
Where are glomerular capillaries formed between
Between the afferent and efferent arterioles
Efferent arterioles give rise to
Peritubular capillaries
What does the renal corpuscle do
It is the site of plasma filtration
What is the renal corpuscle comprised of
Glomerulus
Bowmans capsule
What 2 things are the kidney made up of
Corpuscle
Tubule
The collecting ducts and papillary ducts drain urine where
To the renal pelvis and ureter
What do the kidneys do
They function to regulate volume and chemical composition of body fluids
How much of nephrons are cortical nephrons
80-85%
Where are the renal corpuscles
Outer cortex an loops of henle
How much nephrons are the juxtamedullary nephrons
15-20%
What is the length and diameter of the ureter
10-12” long
1-10mm
Where does the ureter extend to
From renal pelvis to bladder
What is the position of the bladder
Pelvic cavity posterior to the pubic symphysis
What is the smooth triangular area of the bladder called
Trigone
Where does the ureter enter in the urinary bladder
Near two posterior points in the triangle
Where does the ureter drain in the urinary bladder
From the anterior point of the triangle
Location of the bladder in females
Anterior to vagina
Inferior to uterus
Location of bladder in males
Anterior to rectum
What is the bladders fluid capacity
700-800mL
Name the 3 layers of the urinary bladder wall
Mucosa
Muscularis
Adventitia layer of loose connective tissue
How does the body know we need to micturate
Due to stretch receptor signals that travel to the spinal cord and brain when volume exceeds 200-400ml
Where are signals sent if we need a pee
Sent to micturition centre in sacral spinal cord S2 and S3
What fibres cause the bladder to contract
Parasympathetic fibres
What muscles cause the bladder to relax
External and internal sphincter
What part of the brain can cause micturition or delay it
Cerebral cortex
