Renal system Flashcards
What are the 3 functions of the Renal system
- formation of urine
- elimination of waste products
- homeostasis
Where is urine formed
- formed in the kidneys
What does the kidneys eliminate
eliminate waste products such as
- drugs
- toxins
- nitrogensous waste
what does homeostasis control
- water balance
- blood pressure regulation
- red blood cell production
- electrolyte balance
- acid-base balance in the blood
- activation of vitamin D
- Gluconeogenesis
How Many kidneys do people have
2
Kidneys are well protected - what makes them protected
- thick outer fibrous capsule
- surrounded by bed of fat
- protected by lower ribs
what are the different tissues
- the cortex
- the outer fibrous capsule
- the medulla
where are the kidneys positioned
- they are positioned in the upper posterior abdominal wall
function of the outer fibrous capsule
- protection
function of the cortex
- provides a space for arterioles and venues from the renal artery and vein - to help perfuse the nephrons of the kidneys
- erythropoietin (EPO) is produced here - used to create new red blood cells
What is the function of the medulla
- regulate the concentration of urine
- contains part of the nephron the loop of Henle and the collecting duct
- it is hypertonic so it can filtrate the nephron by reabsorbing water due to its higher osmotic pressure
What is the ureters function
- to carry and drain urine from the kidneys to the urinary bladder via peristalsis - propelling urine through the tubes
What are the properties of the Ureter
- a smooth hollow muscular tube
- 25-30cm long
What is the tissue structure that makes up the Ureter
- outer fibrous connective tissue
- middle muscular layer
- inner mucosa layer
What moves the urine through the Ureters
- what happens if the volume of urine produced increases
Peristalsis - the smooth hollow muscle layer propels urine through to the bladder
- when the volume of urine produced increases the peristalsis frequency increases and happens more often
What stops the urine back flowing up the ureter
- the ureter enters the bladder obliquely with a vesicoureteral valve so as the bladder accumulates urine and the pressure increases it can’t back flow up the ureter
What is the bladders function
- reservoir for urine
Where is the bladder situated
- in the pelvis cavity but when its full it extends to the abdominal cavity
What are the properties of the bladder
- it is a muscular sac that can expands depending on the volume of urine it contains
What is the structure of the bladder
- the outer layer = loose connective tissue containing blood and lymphatic vessels and nerves
- the middle layer = interlacing smooth muscle fibres and elastic tissue loosely arranged in 3 layers - detrusor muscle - when it contracts the bladder empties
- the inner layer = transitional epithelium that readily permits distention of the bladder as it fills
What is the function of the detrusor muscle
- in the middle layer of the bladder when it contracts the bladder empties
What is the structure of the Urethra
- a muscular smooth muscle tube
What is the function of the Urethra
- carries urine from the bladder out of the body
- What is the structure of the urethra at the bladder
- What is its function
- The urethral junction at the bladder is a thickening of the detrusor muscle - it acts as the internal sphincter which prevents bladder leakage
Explain the structure of the external sphincters urethral and its functions
- External sphincter urethral is made up of striated muscle
- it surrounds the outside of the bladder
- it is voluntarily controlled - conscious contraction
- it must relax for urination to occur
Explain the structure of the external sphincters urethral and its functions
- Internal sphincter urethral is the thickening of the continuous detrusor muscle located at the opening of the bladder
- it surrounds bladder and prevents the bladder from leaking
- is is involuntary - controlled by nerve impulses which stimulate relation of internal urethral sphincter
what are the 2 main layers of the female urethra
- the outer muscle layer
- the inner lining of the mucosa
what is the properties of the outer muscle
it has 2 parts
- the inner layer of smooth muscle under autonomic nerve control
- the outer layer of striated voluntary muscle surrounding it
what enters the kidney/nephron to allow blood flow
- renal artery enters and branches into arterioles
where does the renal arteriole enter
the glomerular
what is the afferent arteriole
- the afferent arteriole enters the glomerulus
what is the efferent arteriole
- the efferent arteriole leaves the glomerulus
what is the ‘basic’ pathway of how blood flows into then out of the kidney /nephron
- blood enters the glomerulus via the afferent arteriole
- then blood leaves the glomerulus via the efferent arteriole
- then the efferent artery;e then forms a capillary network which surrounds the nephron
- veins are formed
