Level 2 - Urinary System Part 1 Flashcards
What are the 2 main functions of the kidneys?
- Process blood by shifting out waste product and extra water
- Form urine as a waste to be excreted
What are the accessory organs of the kidneys?
Ureters, urinary bladder, urethra
Regulates the content of blood to maintain “dynamic constancy” or homeostasis of the internal fluid environment within normal limits
Urinary system
What is the vertebral level of the kidneys?
T12-L3
T/F
It is possible to only see one kidney at level T12
True
Because the left kidney is higher
T/F
It is possible to only see one kidney at L3
True
Because the left is higher, only the right may be seen at L3
Concave notch on medial surface where vessels and tubes enter and exit kidney
Hilum
What vertebral level is the Hilum situated?
L1
What is the size of the kidney?
11cmx7cmx3cm
Which kidney is larger and situated higher?why?
Left kidney is larger and higher than right
Liver sits on top of right kidney
Where are the kidneys located?
In the retroperitoneal position, posterior to the parietal peritoneum (abdomen) against the posterior abdominal wall
*behind abdomen, beside L spine
T/F
The superior poles of the kidneys extend above the level of the 12th rib at the lower edge of the thoracic parietal pleura
True
What anchors and surrounds the kidneys?
Renal fasciae (connective tissue) anchors the kidneys to surrounding structures
Renal fat pads surround kidneys for heavy cushioning
The kidney is encased in a fibrous capsule
Outer region of the kidney, under the capsule
Renal cortex
Inner portion of the kidney that has renal pyramids
Medulla
Comprise much of medullary tissue, they are roughly triangular in shape with the larger end called the base and the papilla is at the tip of each pyramid
Facing the Hilum and releases urine through multiple ducts into the calyces
Renal pyramids
Cuplike structure at each renal papilla to collect urine; minor calyces join to form major calyces, which in turn form the renal pelvis
Calyx
Where cortical (cortex) tissue dips into the medulla between pyramids
Renal columns
What part of the renal pyramids point towards the Hilum?
Papilla (point)
Base is against cortex
T/F
Renal pelvis narrows as it exits the kidney to become the ureter; acts as a collection basin to drain urine from the kidney
True
What happens when a kidney stone is stuck in the ureter?
Renal pelvis backs up and expands
Large branch of abdominal aorta; brings blood into each kidney at the Hilum
Renal artery
T/F
Kidneys are highly vascular
True
What arteries arch over the base of the renal pyramids?
Arcuate arteries
Tube running from each kidney to the urinary bladder; composed of 3 layers: mucous lining (transitional), muscular middle layer made of smooth muscle that propels urine by peristalsis, and a fibrous CT outer layer
Ureter
Where do the ureters begin?
Renal pelvis in the Hilum area (L1)
*they are retroperitoneal
Where do the ureters attach to the bladder?
Trigone floor (bottom of bladder)
Why do the ureters run obliquely through the bladder wall for 2cm?
Helps the ureters act as valves when bladder is full to prevent back flow
How many openings does the trigone floor have?
3
2 for ureters (posterior)
1 for urethra (anterior)
Muscular, collapsible bag located behind the pubic symphysis for males and females
Made mostly of smooth muscle tissue called the detrusor muscle
Sits below parietal peritoneum, which covers only the superior surface and is retroperitoneal
Urinary bladder
Where does the bladder sit in females?
Anterior to vagina and uterus
Where does the bladder sit in males?
Superior to the prostate
What is the function of the bladder?
Reservoir for urine before it leaves that body
Aided by the urethra, it expels urine from the body
Small mucous membrane lined tube extending from the trigone to the exterior of the body, external urinary meatus
Urethra
Where is the urethra located in females, and how long is it?
Lies posterior to the pubic symphysis and anterior to the vagina
Approx. 3cm long
Where is the urethra located in males and how long is it?
Bladder -> prostate gland (joined by 2 ejaculatory ducts) -> base of penis -> center of penis -> ending at external urinary meatus
Approx. 20cm long
What is different about the male urethra then the female urethra?
Male urethra is part of the urinary system as well as the reproductive system
Mechanism for voiding bladder
Urination or micturition
What happens as bladder volume increases?
Micturation contractions (of detrusor muscles) increase and the internal urethral sphincter relaxes involuntary
External urethral sphincter muscle contracts at first, then at appropriate time relaxes to release urine voluntary
How much urine can the average bladder hold?
250ml
Involuntary voiding
Incontinence
The microscopic functional units, comprise the bulk of the kidney
Nephrons
What is each nephron made up of?
Two regions (renal corpuscle and renal tubule) and connects to shared collecting duct
Made up of the Bowman’s capsule and glomerulus. It is where fluid is filtered out of blood
Renal corpuscle
*in cortex
Made up of the proximal convoluted tubule, the loop of Henle and the distal convoluted tubule
Renal tubule (in medulla)
*the filtrate will leave the renal corpuscle and flow through the renal tubule where much is then returned back to blood
Will carry remaining filtrate to leave as urine
Collecting duct
Cup shaped mouth of the nephron
Bowman capsule
*formed by 2 layers of epithelial cells
Space between them is called Bowman’s space
Capillary network inside the renal corpuscle
Glomerulus
T/F
The glomerulus is one of the most important capillary networks for survival
True
