EXCRETION
BY: PUAN ROSITA MOHD YUSOF BANDAR BUKIT MAHKOTA (update Feb 2012)
HUMAN EXCRETION Metabolism – all the chemical processes that take place in the body. Excretion – the elimination of the metabolic waste products. Organ of excretion: a) Skin b) Lungs c) Kidneys Importance of excretion: Disposal of toxic/poisonous waste. Eg urea & CO2 Disposal of excess substances. Eg salts and water
Organ perkumuhan Bahan perkumuhan
Kulit
Air, garam mineral dan urea
Peparu
Wap air dan gas karbon dioksida
Ginjal
Air, garam mineral dan urea.
Human urinary system The urinary system (also called the excretory system) is the organ system that produces, stores, and eliminates urine. In humans it includes two kidneys, two ureters, the bladder and the urethra. Blood is carried to each kidney by renal artery and away from kidney by renal vein.
The kidneys are bean-shaped organs that lie at he back of abdominal cavity, just above the waistline where left kidney is slightly highe than the right kidney. The organ is about the size of a human fist. The blood is filtered within kidney where waste product eg urea and xs substances are converted into urine.
Ureters carry urine from the kidneys to the urinary bladder. Urinary bladder stores urine. When the urinary wall contracts, urine is expelled to the exterior via urethra in the process known as URINATION.
The kidneys. Is protected by and covered by thick layers of fat. in longitudinal section, there are two regions outer darker region – cortex pale inner region – medulla: filled with cone shaped tissues called pyramids which opens into a funnel shaped cavity called pelvis. one kidney has at least one million tiny blood filters
FUNCTIONS OF KIDNEYS: 1.Remove nitrogenous waste products. 2.Balance the water and mineral content in body. 3.Controls the amount of mineral salts in the body fluid. 4.Maintain pH of blood and tissue fluids.
FUNGSI-FUNGSI GINJAL: 1.Mengawal paras glukosa dalam darah 2.Mengawal keseimbangan air dalam darah. 3.Mengawal kandungan garam mineral dalam darah. 4.Mengekalkan nilai pH darah.
KIDNEY FAILURE. CAUSES OF KIDNEY FAILURE: • Bacterial infection • Injury • High blood pressure 2 ways of treatment: • dialysis machine • kidney transplant
Haemodialysis • blood flows through a long tube known as dialysis tube • the dialysis tube is surrounded by a solution known as dialysate (contain dissolve sugar and salts, just like plasma). It runs in opposite direction to blood flow. • urea and xs salts pass from the blood into the dialysate by diffusion. • dialysis treatment is normally take place 2-3 times a week.
KIDNEY TRANSPLANT. ďƒ˜ only from suitable donor (matched tissue)
EXCRETION IN PLANTS
• Animals eat a lot of protein and some of the amino acids are not needed by them which later converted to urea. •Plant do not have specialised excretory organs. Some are converted to latex(tyre/gloves), resin(paint) and gum and are released when the plant dies. •Plants less active than animals so they accumulates waste more slowly.
EXCRETORY PRODUCT
SOURCE
METHOD OF EXCRETION
Respiration
Removed from tissues by diffusion thru intercellular spaces in the leaves at night,stems and roots.in leaves CO2 escapes thru stomata
Oxygen
Photosynthesis
During the day, oxygen is lost from the leaves by diffusion through stomata
Water
Photosynthesis
Water is lost through transpiration
Calcium oxalate
Metabolism
Deposited in the form of crystals in leaves and stem.
Metabolism
Stored in leaves and fruits and are therefore removed when these are shed from plants
Carbon dioxide
tannins
SUMBER
BAHAN KUMUH
KEGUNAAN
Batang pokok ru
Damar/resin
Membuat cat/varnis
Kulit pokok bakau
Tannin
Membuat dakwat
Kulit pokok kina
Kuinin
Ubat malaria
Daun pokok tembakau nikotina
Membuat ubat, dadah dan racun
Daun pokok popi
morfina
Membuat ubat dan dadah
Kulit pokok getah
lateks
Membuat barangan getah
Daun dan bunga
minyak
Membuat minyak wangi
Calcium oxalate crystals