Excretory System Worksheets Free Sample Thank you so much for downloading the sample resource. We hope it has been useful for you in the classroom and that your students enjoy the activities. KidsKonnect is a very small family run business and we are proud that we can offer education to over 40 countries globally. The more support we have from our Premium members the more resources we can release. If you want the more comprehensive and detailed worksheet collection then please upgrade to our Premium plan and support our quest to make education affordable for all. Don’t forget to come back and download the new material we add every week! Thanks for supporting KidsKonnect. We can provide teachers with low-cost, high-quality teaching resources because of our loyal subscribers and hope to serve you for many years to come. - Ryan, Beth & Nicola :) Excretory System Facts The excretory system is a collection of organs with the main function of excretion or the process of disposing waste from the body. Moreover, the excretory system is responsible for the elimination of waste produced by the chemical processes in the body to regulate its metabolism. MAIN FUNCTIONS ★ ★ ★ ★ It eliminates waste products in the body such as urea, uric acid ammonia, and other waste products. These products are excreted from the body through urine. The excretory system helps in maintaining the osmotic level of blood and plasma. It is involved in the process of osmoregulation, a process that maintains the proper amount of electrolytes in the body regardless of external factors like temperature, diet, and weather conditions. KIDSKONNECT.COM Excretory System Facts ★ ★ An electrolyte is a substance that produces an electrically conductive solution when dissolved in a polar solvent like water. It is maintained through osmoregulation and is involved in vital processes of the body. When taking medication, the excretory system metabolizes or processes the drugs that are not processed in the liver. MAIN ORGANS AND THEIR FUNCTIONS KIDNEYS ★ ★ ★ ★ ★ ★ ★ The kidneys are the main organ of the excretory system. Each individual has a pair of kidneys, located on each side of the spine at the level of the liver. The kidneys are divided into three regions: the renal cortex, renal medulla, and renal pelvis. The Kidneys The renal cortex is the outer region of the kidney. It is the region between the renal capsule and the renal medulla. It is made up of blood vessels connected to the nephrons. Erythropotein, a hormone needed for the synthesis of new red blood cells, is also produced in the renal cortex. The renal medulla is the inner region of the kidney. It is where renal pyramids are found. These are dense networks of nephrons. This is where blood is filtered and water and ion levels are regulated. The renal pelvis is the region where blood enters and exits the kidney. It is also where urine exits from the ureters and empties into the urinary bladder. It is the region that connects the kidney to the rest of the body. KIDSKONNECT.COM Excretory System Facts ★ Nephrons are found in the kidneys and are responsible for the filtration of blood and regulation of chemicals. The Kidney URETER ★ ★ The ureter is connected to the renal pelvis. It is a muscular tube whose sole function is to carry urine from the kidneys to the bladder. URINARY BLADDER ★ ★ ★ ★ The urinary bladder is a sac-like structure, lined with a smooth layer of muscle, where the ureter transports urine from the kidneys. It stores urine until it is expelled from the body via microturition, the act of expelling urine from the body. The placement of the urinary bladder differs in gender. Microturition has two main stages: ○ Resting or Filling stage ■ This is the phase where urine is transported from the kidney via the ureter. ■ The ureter is obliquely placed in the bladder. Its opening to the bladder is not guarded by any muscle; this prevents the urine from re-entering the ureter and allows the bladder (the detrusor muscle) to relax and store more urine. KIDSKONNECT.COM Excretory System Facts ○ Voiding stage ■ Voiding is the stage where urine is expelled. ■ In this stage, the bladder and urethra are involved. ■ The detrusor muscle, which was relaxing at the resting or filling stage, contracts when the bladderʼs capacity is reached. ■ The urethraʼs muscles, internal and external muscles, relax. ■ The nervous system is also involved in the process. ■ As the bladder reaches its capacity, the receptors on the walls of the bladder send an impulse through the pelvic nerve to the brain via the spinal cord. The Urinary Tract KIDSKONNECT.COM Excretory System Facts URETHRA ★ ★ ★ ★ The urethra is a tube that arises from the urinary bladder and functions to expel urine to the outside by microturition. The urethra is the pathway for both urine and sperm for males. Men have longer urethras than women. The opening of the urethra is guarded by a sphincter that is autonomically controlled. OTHER EXCRETORY ORGANS ★ ★ ★ ★ ★ ★ ★ ★ The skin is the largest organ in the body. The skin excretes body waste via sweating. The lungs are the main organ of the respiratory system. The lungs expel waste by taking in oxygen and breathing out carbon dioxide. The lungs also expel water in the form of vapor. The liver is also important in the excretion of waste in the body. It is the first to process hormones, fats, alcohol, and drugs. While few drugs are directly eliminated in the kidneys, drugs are first or partially processed in the liver. The liver is found above the stomach KIDSKONNECT.COM Name: ______________ Incomplete Boxes Fill in the boxes with the correct letters to complete the concept being described. 1. This system is responsible for disposing waste from an organism's body. E 2. C O S It is a muscular tube that carries urine from the kidneys to the bladder. R 3. R The waste material expelled through the largest organ of the body. S 4. T This is a sac-like structure, lined with smooth muscle layer, where the ureters transport urine from the kidneys. U 5. M I B D D Found in the kidneys and responsible for the filtration of blood and regulation of chemicals. N P H EXCRETORY SYSTEM WORKSHEETS S KIDSKONNECT.COM Name: ______________ Incomplete Boxes ANSWER KEY 1. This system is responsible for disposing waste from an organism's body. E X 2. C R E T O R R S T E M E T E R W E A T This is a sac-like structure, lined with smooth muscle layer, where the ureters transport urine from the kidneys. U 5. Y The waste material expelled through the largest organ of the body. S 4. S It is a muscular tube that carries urine from the kidneys to the bladder. U 3. Y R I N A R Y B L A D D E R Found in the kidneys and responsible for the filtration of blood and regulation of chemicals. N E P H R O EXCRETORY SYSTEM WORKSHEETS N S KIDSKONNECT.COM Copyright Notice This resource is licensed under the Creative Commons Attribution-NonCommercial 4.0 International license. You are free to: ● Share — copy and redistribute the material in any medium or format ● Adapt — remix, transform, and build upon the material Under the following terms: ● Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use. ● NonCommercial — You may not use the material for commercial purposes. For more information on this license, visit the following link: http://creativecommons.org/licenses/by-nc/4.0/ Thank you! KIDSKONNECT.COM
