Topic 13 Flashcards
Excretion meaning
The removal drew m the body of waste products
Name the excretory organs and what they do
lungs - excrete carbon dioxide
liver - processes toxic materials and makes them harmless
kidneys - excrete urea and ions
What are the excretory products and what do they do
Carbon dioxide - made in body tissues during respiration. It is transported to the lungs in the blood plasma. It diffuses out the blood into the air in the alveoli and is breathed out
Urea - is made in the liver from excess amino acids. It is carried to the kidneys in the plasma where it is filtered out and leaves the body dissolved in the form of urine
What is assimilation
That the food molecules that have been absorbed now become part of the cells or are used by the cells
Liver functions for assimilation
Stores glucose by removing it from blood and storing as glycogen - helps to regulate concentration of glucose in the blood
Uses amino acids to make proteins
Breaks down excess amino acids
Converts fatty acids and glycerol into fat
Produces cholesterol from fats
What is deamination
Deamination is a biological process where an amino group is removed from an amino acid, forming ammonia. It mainly occurs in the liver. The ammonia is then converted into urea, which is less toxic, and excreted by the kidneys
- the breakdown of excess amino acids in the liver to form ammonia which is made into urea
Difference between excretion and egestion
Excretion - produced by body cells in metabolism
Egestion - have been eaten and have passed through the alimentary canal without being digested and absorbed in the bloodstream like fibre
Parts of urinary system
Renal vein
Kidney
Renal artery
Ureters
Bladder
Urethra
Ring of muscle
Renal vein and renal artery role
Renal vein - takes cleaned blood away from the kidneys
Renal artery - brings waste to the kidneys in the blood
Kidneys and ureters roles
Kidneys - remove urea and other chemicals from the blood
Ureters - carry urine down to the bladder
Bladder urethra and ring of muscle roles
Bladder - stores urine
Urethra - carriers urine out of the body
Ring of muscle - keeps the bladder closed until you urinate
3 areas of the kidneys
Medulla - brown outer area
Cortex - reddish area
Pelvis - white area
Function of kidney tubules
Filter the blood and remove waste chemicals and determine how much water is excreted
The chemicals - removed from the body as urine which flows from the kidneys down the ureter and is stored in the bladder
Glomerulus meaning
Closely packed group of capillaries
Reabsorprion two parts
Micro villa
Mitochondria
