Excretory System Flashcards
What is the function of the excretory system?
The excretory system removes waste products and excess substances (like water, salts, and urea) from the body to maintain internal balance (homeostasis).
What are the main organs of the excretory system?
The primary organs involved are the kidneys, ureters, bladder, and urethra.
What is the role of the kidneys in the excretory system?
The kidneys filter blood, removing waste products like urea, excess water, and salts to produce urine. They also regulate electrolyte balance and help control blood pressure through the renin-angiotensin system.
What are the nephrons?
Nephrons are the functional units of the kidneys. Each nephron consists of a glomerulus and a tubule . Nephrons filter blood and produce urine.
What is glomerular filtration?
Glomerular filtration is the process where blood enters the glomerulus, and waste products like urea, excess salts, and water pass into the Bowman’s capsule, beginning the formation of urine.
What happens during tubular reabsorption?
In tubular reabsorption, essential substances like glucose, amino acids, and water are reabsorbed from the renal tubules back into the blood, ensuring that the body retains necessary nutrients and maintains fluid balance.
What is tubular secretion?
Tubular secretion is the process by which additional waste products, such as hydrogen ions (H⁺) and creatinine, are secreted into the renal tubules from the blood, allowing further elimination of toxins.
What is the function of the ureters?
The ureters are muscular tubes that carry urine from the kidneys to the bladder for storage.
What is the function of the urinary bladder?
The urinary bladder is a hollow organ that stores urine produced by the kidneys until it is ready to be expelled from the body.
What is the function of the urethra?
The urethra is the tube that carries urine from the bladder to the outside of the body during urination.
What is urine formation?
Urine formation involves three main processes:
Filtration – Blood is filtered through the glomerulus into the Bowman’s capsule.
Reabsorption – Useful substances are reabsorbed into the bloodstream.
Secretion – Waste products and excess substances are secreted into the renal tubules to form urine.
What is micturition?
Micturition is the process of urination, where the bladder contracts and urine is expelled through the urethra.
How do the kidneys help regulate fluid balance?
The kidneys regulate fluid balance by adjusting the amount of water reabsorbed into the bloodstream during the filtration process. If the body needs more water, the kidneys reabsorb more; if excess water is present, less is reabsorbed, and more is excreted as urine.
How do the kidneys help regulate electrolyte balance?
The kidneys help maintain electrolyte balance by adjusting the reabsorption of ions such as sodium (Na⁺), potassium (K⁺), and calcium (Ca²⁺) in the renal tubules. This helps control the levels of electrolytes in the blood.
How do kidneys control blood pressure?
The kidneys help regulate blood pressure through the renin-angiotensin-aldosterone system (RAAS). When blood pressure drops, the kidneys release renin, which activates a series of steps that lead to the production of angiotensin II, a hormone that constricts blood vessels and stimulates aldosterone secretion, increasing sodium and water retention, which raises blood pressure.
What are the main waste products excreted by the kidneys?
The kidneys excrete urea, creatinine, uric acid, and excess electrolytes like sodium, potassium, and chloride.
What is urea and how is it produced?
Urea is a nitrogenous waste product produced in the liver from the breakdown of amino acids. It is transported to the kidneys for excretion in the urine.
What is creatinine, and why is it important in assessing kidney function?
Creatinine is a waste product produced from the breakdown of creatine in muscles.
What is the excretory systems 3 main functions?
- removing metabolic waste
- Balancing blood PH
- Maintaining water balance
What is deamination?
The removal of nitrogen group and it occurs in the liver
The urinary system consists of what 5 main organs?
Renal Arteries, Kidneys, Uretes, Brain, Sphincter
What job does your brain have in the excretory system?
signals when your bladder stretches and is full of excretion
What main organs are in a kidney? And where are they all located?
Cortex - outer layer of connective tissue
Medulla - inner layer of connective tissue
Renal Pelvis - hollow inner chamber of the kidney
What are the 7 organs in the Renal Cortex and Renal Medulla for urination?
- Glomerulus
- Bowmans capsule
- Proximal convoluted tubule
- Descending loop of Henle
- Ascending loop of Henle
- Distal convoluted tubule
- Collecting duct
What is Antidiuretic Hormone? (ADH)
Increase water absorption in kidneys. Works by increasing permeability of distal tubule and collecting duct to water. Producted in Hypothalamus
What is a osmoreceptor?
located in hypothalamus, detects changes in osmotic pressure when cells shrink or expand (thirst)
What is Aldosterone?
Hormone produced by adrenal glands, acts on nephrons increasing not absorption resulting in more water reabsorption
What is Diabetes Insipidus?
effects the water regulation in the body, insufficient ADH levels lead to excessive urination and dehydration
What is Renal insufficiency?
kidneys cannot maintain homeostasis from nephron damage
What is Urinary Tract Infection (UTI)?
bacteria living in intestine that spreads from anal to urethra
What are Kidney Stones?
crystalline formations of excess calcium in kidneys
When would you get a Kidney Transplant?
When your kidney has 10 percent or less of function
