Excretion Flashcards
(94 cards)
The sum total of all the chemical reactions that take place in a cell.
Metabolism.
Why does metabolic waste need to be removed continuously?
It will poison the cells and inhibit normal functioning if allowed to accumulate.
How does metabolic waste leave the cells?
It diffuses out the cells via the tissue fluid that surrounds them, to the blood vessels.
What is an excretory organ?
An organ with the ability to remove waste products.
Where does the blood carry metabolic waste?
Excretory organs.
What are the four excretory organs/organ pairs?
Lungs.
Kidneys and bladder.
Liver and intestines.
Skin.
What do the lungs excrete?
CO2, water vapour and heat.
What do the kidneys and bladder excrete?
Urine.
What does urine consist of?
Excess water, mineral salts and nitrogenous waste products (namely urea, uric acid and creatinine).
What do the liver and intestine excrete?
Urea and bile pigments.
What does the skin excrete?
Sweat (via sweat glands).
What does sweat consist of?
Excess sweat, salts and a small amount of urea.
What are the origins of metabolic waste?
Cellular respiration - CO2 and excess water.
Deamination of amino acids - urea.
Metabolism of nucleic acids - uric acid.
Creatinine phosphate in the cells - creatinine.
Haemoglobin breakdown in the liver - bile pigments.
Which organs makeup the urinary system?
2 kidneys, 2 ureters, the bladder and the urethra.
Which two blood vessels are associated with the urinary system?
Renal arteries and renal veins.
Where are the two kidneys?
In the abdominal cavity, on either side of the vertebral column, just below the diaphragm.
Where do the kidneys receive oxygenated, metabolic waste rich, blood from?
The renal arteries.
Which blood vessel carries deoxygenated, purified, blood away from the kidneys?
The renal veins.
What do the 2 ureters do?
They extend from the kidneys and separately open into the bladder.
What is the structure and function of the kidney?
Thin walled muscular sack which temporarily stores urine.
What does the urethra do?
Transports urine from the bladder to the exterior.
What controls urine flow to the urethra from the bladder?
A sphincter muscle.
Describe the external structure of the kidneys.
Dark red, bean-shaped organ with the concave side facing the vertebral column.
What is the hilum?
The indentation on the concave side of the kidney where the renal artery enters and the renal vein and ureter leave the kidney.