Excretory system
Excretion The process of removing waste produced in the cells of living organism. Ammonotelism Ammonia Aquatic invertebrates, bony fishes, aquatic amphibians, tadpoles, aquatic insects Ureotelism Urea Terrestrial and semi-aquatic amphibians, cartilaginous fishes, aquatic/semi aquatic reptiles Uricotelism Uric acid Birds, terrestrial reptiles, insects, land snails, some land crustaceans.
Human excretory system A pair of kidneys One pair of ureters A urinary bladder Urethra
Human excretory system kidneys Ureters Urinary bladder Urethra
Kidney-structure Reddish brown Bean-shaped 10-12 cm length 5-7 cm width, 2-3 cm thick 150 gms average weight-male 135 gms average weight-female
Location of kidney
Anatomy of kidney
Enclosed in a tough, three-layered fibrous capsule. Anatomy of kidney Enclosed in a tough, three-layered fibrous capsule. Concave side-Opening-hilum/hilus. Hilum leads to funnel shaped cavity-Renal pelvis Projections-calyces(major and minor) Outer dark region-cortex Inner lighter region-medulla. Medulla-conical projections-renal pyramids(medullary pyramids) minor calyces Major calyces –funnel shaped structure renal pelvis ureter
Between the medullary pyramids-cortex extends into medulla-renal column-Columns of Bertini
Structure of nephron 2.Renal tubule 1.Malpighian corpuscle (Renal Corpuscle) cortex Malpighian corpuscle renal tubules medulla
Peritubular capillaries, vasa recta & ducts of Bellini
Role of liver in excretion Excretion of cholesterol, steroid hormones, vitamins, drugs and other waste materials through bile. Ornithine cycle-converts ammonia into urea Hemoglobin waste- bile pigments-bilirubin and biliverdin
Role of skin in excretion