Excretion is the elimination of waste substances
Classified in Biology
Written at on 
English with a size of 2.36 KB.
Excretion of CO² by cellular respiration (by breathing/blood...)
Urine: 95% water 5% waste/yellow coloured- urea
Sweat: 99% water
Kidneys:
Renal vein(blue)/renal artery(red)
Cortex\renal pelvis\medulla\ureters \ bladder\urethra
Function: filtration/reabsorbed/excret
Blood: 45% blood cell/ 55% blood plasma
Cells in blood/mm³: white(8000), platelets(250000), red (+5million)
Red: oxygen
Platelets: help stop bledding
White: protect the body from infection
Blood vessels:
Arteries (thick/stronger walls) high pressure, blood goes to...
Veins: thinner , low pressure, from organs to heart
Capillares: thinner(connect)
Heart:
Myocardium. Atria 1
Atria2.
Ventricle 1
Ventricle 2
Heartbeat
1atrial contractiin (systole) atriash-ventricles
2 ventricular contraction (systole)ventricles-out
3 diastole (relaxation)out-ralaxation
Lungs:
Medium - aorta
Parts: veins (left(vena cavae) and right(pulmonary artery))
Flow of blood:
Blood exits the heart from right ventricle and travels to lungs trough pulmonary arteries.
Gas exchange→ blood picks up O² and releases CO²
The blood returns to the pulmonary veins, entering the heart at the left atrium.