Excretion Flashcards
deamination
The process that remove the amino group from amino acids
urea
The liver combines ammonia with carbon dioxide to form urea, a much less toxic product
uric acid
the liver also breaks down nucleic acids to produce a waste product called uric acid
kidney
- Removes waste products from deamination
- maintain water balance in body (homeostasis)
renal cortex
An outer layer of connective tissues that enclose the kidney
renal medulla
The middle layer of the kidney
renal pelvis
A hollow inner layer in which the ureter, arteries and veins attach to the kidney
bladder
- Can hold up to 200ml of urine when relaxed
- prevents urine from leaving through a sphincter muscle
ureter
- Transports urine from the kidney to the bladder
- connects the kidneys to the bladder through a specific pathway
- allows urine to move from the kidneys renal pelvis to the bladder
urethra
- Part of the urine pathway from the bladder to the outside of the body
- serves as the final passage for urine to exitduring urination
-controlled by a voluntary sphincter musclethat regulates urine release
nephron
The functional unit of the kidney responsible for urine production.
renal vein
- Carries blood away from the kidneys afterfiltration
- transports deoxygenated blood from the kidneys
- involved in the process of removing nitrogen groups during metabolic processes
renal artery
- Carries oxygenated blood tothe kidneys
- supplies blood to the nephron through the efferent arteriole
- initiates the blood filtration process in the kidney
afferent arteriole
- Supplies blood to the nephron from the renal artery
- branches into the glomerulus, which is a capillary network where initial blood filtration occurs
- part of the unique blood vessel arrangement in the kidney’s filtration system
efferent arteriole
- Part of the unique blood vessel system in the kidney’s nephron
- follows the glomerulus in the blood filtration pathway
- connects the glomerulus to the capillary network
glomerulus
Located in the nephron,the glomerulus is a specialized capillary network responsible for initial blood filtration
Bowman’s Capsule
- Initial filtration site in the nephron where blood filtration begins
- receives filtrate from theglomerulus
proximal tube
- Reabsorbs Substances: vitamins, amino acids, glucose, and sodium
- loss of water increases solute concentration
- urea can also leave the tube
Loop of Henle
Water Reabsorption; Descending loop
- permeable only to water
- water leaves the tubule into instertitial fluid via osmosis
- driven by high salt concentrationin the medulla
Salt Concentration Gradiant; Ascending loop
- permeable only to ions
- creates a salt concentration gradient towards the bottom of the loop
- induces chloride ion diffusion
- concentrates urea in the tubule
Distal tube
- Secretes waste materials; actively transport out sodium ions, and chloride ions follow sodium ions
Ion and pH balance
- draws in potassium and hydrogen ions
- helps maintain pH balance around 7.4
- uses chemoreceptors to monitor and adjust ion concentrations
Sodium regulation
- sodium pumps controlled by aldosterone
- responds to blood sodium fluctuations
- allows sodium to be drawn back into the bloodstream
Tubular Secretion
- adds excess ions and substances to the filtrate from surrounding capillaries
- considered a form of “reabsorption in reverse”
collecting ducts
Transports urine from the distal tubule to the renal pelvis and eventually to the ureter
filtration
- Filtration is the first step in urine production
- not all blood components Pass through the filter
- useful molecules can be reabsorbed later in the nephron
tubular reabsorption
Reabsorption involves returning useful molecules from the filtrate back into the bloodstream through various transport mechanisms
tubular secretion
- A process where ions and substances are added to the filtrate from surrounding capillaries
- often described as “reabsorption in reverse”
- occurs in distal tube
- involves actively transporting substances; sodium ions are actively transported out and Cl ions follow sodium ions
water reabsorption
- Collecting duct reabsorption
- controlled by ADH from the pituitary gland
- Oslo receptors monitor pressure and blood concentration
chemoreceptors
- Monitors blood pH to help maintain homeostasis
- can move H+ ions and HCO3- ions to keep blood pH around 7.4
tubular secretion
- Excess ions and other substances are actively added to the filtrate from surrounding capillaries
- maintains blood pH levels by secreting substances into the filtrate
- actively transports sodium ions out of the nephron with chloride ions following
- often described as “reabsorption in reverse”
- allows the kidney to remove specific substances from the blood and excrete them in urine.
osmoreceptors
- Monitor water pressure and levels in the blood
urinary tract infection (UTI)
- Bacterial or vita infection in the bladder- cystitis, infection in urethra - urethritis
- symptoms include burning sensation when urinating: bloody or brown urine
- treatment- antibiotics
diabetes mellitus
- Inadequate secretion of insulin leads to high blood-sugar levels endocrine disorder which affects the kidney)
- excess glucose is secreted in urine
- large volumes of urine produced, often thirsty (water follows the solute/glucose in nephron)
Kidney stones
- Crystalline formations due to excess calcium in urine
- caused by recurrent utls, insufficient water consumption
- treatment varies on size of stones-medications, ultrasound shock waves, surgery
nephritis
- Inflammation of the nephrons - affects the blood vessels in the glomerulus and can alter permeability
renal failure
- A condition where kidneys cannot maintain homeostasis and perform their essential functions
hemodialysis
- A type of dialysis that acts as an artificial kidney
- performs blood cleansing through a specific process
- uses a semipermeable membrane
- allows diffusion of dissolved substances
- moves substances through passive transport
- transfers high blood solutes into the dialysis solution
peritoneal dialysis
-used when kidneys cannot effectively filter waste and maintain homeostasis
- involves diffusion of dissolved substances through a semipermeable membrane
- moves substances through passive transport
- transfers high blood solutes into the dialysis solution
Liver
- Breaks down RBC
- processes lactic acid from anaerobic respiration
- deaminates amino acids
- converts proteins into waste products found in urine
