The Excretory System Flashcards
Excretion organs
- Lungs/respiratory system
- Kidneys/excretory system
- Liver
- Bladder/excretory system
- Skin
Lungs/respiratory system:
1. Substance excreted
2. Origin of substance excreted
- CO2 + water vapour
- Cellular respiration
Kidneys/excretory system:
1. Substance excreted
2. Origin of substance excreted
- Urine (urea, uric acid, water, salts, ammonia)
- Metabolic waste
Liver:
1. Substance excreted
2. Origin of substance excreted
- Bile pigments into the alimentary canal
- Bile and dead red blood cells
Bladder/excretory system:
1. Substance excreted
2. Origin of substance excreted
- Urine
- Metabolic waste
Skin:
1. Substance excreted
2. Origin of substance excreted
- Sweat (water, salts, urea)
- Metabolic waste
Urinary system consist of
- Renal arteries
- Kidneys
- Renal veins
- Ureters
- Urinary bladder
- Urethra
Renal arteries:
1. Number in system
2. Function/description
- 2
- Constantly transport blood to the kidneys
Kidneys:
1. Number in system
2. Function/description
- 2
- Composed of millions of nephrons
Constantly filter 170 - 200 litres of blood to produce urine daily
Renal veins:
1. Number in system
2. Function/description
- 2
- Returns filtered blood/useful nutrients back into the bloodstream
Ureters:
1. Number in system
2. Function/description
- 2
- Carry urine form the kidneys to the urinary bladder
Urinary bladder:
1. Number in system
2. Function/description
- 1
- Temporarily stores urine until it’s released from the body
Urethra:
1. Number in system
2. Function/description
- 1
- Tube that carries urine from the urinary bladder to the outside of the body
Outer end of urethra is controlled by a circular muscle called a sphincter
Structure in bladder and its function
Rugae - allows bladder to expand
Kidney characteristics
- Bean shaped
- Located against the back muscles in the upper abdominal area, lower rib
- Right kidney is a bit lower than the left kidney
Kidney function
To remove metabolic waste, liquid waste and excess water from the organism
________ blood filtered by the kidney ________
7-8 litres
20-25 times a day
Functional unit of a kidney
Nephron
Nephron is used to
- Separate water, ions and small molecules from the blood
- Filter out wastes and toxins
- Return needed molecules to the blood
Each kidney has about ______ nephrons
1 million
Tiny arteries
Arteriole
Arteriole names and description
- Afferent Arteriole = filtered blood into the nephron
- Efferent Arteriole = filtered blood out of the nephron
_________ carries out the process of _________
Kidney
Excretion
Different processes
- Filtration
- Absorption
- Diffusion
- Excretion
Filtration
- Kidney filters blood to remove unwanted minerals, urea and excess water
- Some water is removed so that metabolic waste products can be excreted in liquid urine
Absorption
- Blood is filtered by kidneys, substances that the body needs are re-absorbed back into the blood so they are not lost in urine
Diffusion
- Substances are transported into and out of the specialised cells of the kidney through the process of diffusion
Excretion
- Wastes and some water passes out of kidney, down ureter to bladder to be passed out of body
Urinary System health issues
- Kidney failure
- Bladder infection
- Kidney Stones
Kidney failure
- Kidney loses ability to properly filter and remove metabolic waste which allows waste to build up in the body
- Very harmful, may be fatal
- Patient will need regular dialysis/hemodialysis
Bladder infection
- Common in women, rare in men
- Bacteria can enter bladder, causing infection
- Causes swelling and pain when urinating
Kidney Stone
- Form when fluid intake is too low, resulting in concentration of solutes in kidney becoming too high
- Small crystal (stone) forms from solutes (salts and minerals)
- Stone may stay in kidney/move down ureter to be excreted in urine
- Larger stone causes severe pain along the urinary tract and may get stuck
- When stone is stuck, it blocks the flow of urine and causes severe pain and bleeding
Major problem with transplantation
Rejection
Donor kidney needs to be as
Similar as possible to be the patients tissue type
Process that cleanses kidneys and description
Plasmophersis - removing antibodies (from a non-match kidney) through a cleaning process
Choosing a patient for a kidney transplant
- Antigens on the surface of every cell determine your tissue type
- Your immune system produces antibodies to foreign antigens
Drug used to try and prevent rejection
Anti-rejection drugs
Disadvantage of using anti-rejection drugs
They suppress your immune system which can make a person vulnerable to infections
Living donor kidney lasts
20-25 years
Deceased donor kidney lasts
15-20 years
When transplanted kidney no longer works
Patient could die/need dialysis again
When patient received transplanted kidney successfully
- Patient no longer need dialysis
- Improved quality of life
- Work and travel easier
- More energy
- Live longer
- Less restrictive diet
Main source of kidneys for transplant
Cadavers (dead bodies/donors)
Advantages for dialysis
- No need for anti-rejection drugs
- Less invasive
Disadvantages for dialysis
- Time consuming
- Requires frequent visits to hospitals and doctors
- Results in unpleasant side effects (cramps, fatigue)
- Physically and emotionally draining
- Limits ability to work and travel
Advantages for kidney transplantation
- Improved quality of life
- Able to travel and work
- More energy
- Less restrictive diet
- Live longer
Disadvantages for kidney transplants
- Difficult to find suitable donor
- Have to take anti-rejection medication which weaken person’s immune system
