Function of kidney in maintaining homeostasis

What Is Homeostasis? Homeostasis refers to the body's need to reach and maintain a certain state of equilibrium. The term was first coined by a physiologist named Walter Cannon in 1926. More specifically, homeostasis is the body's tendency to monitor and maintain internal states, such as temperature and blood sugar, at fairly constant and stable levels. Homeostasis refers to an organism's ability to regulate various physiological processes to keep internal states steady and balanced. These processes take place mostly without our conscious awareness. How Is Homeostasis Maintained? Your body has set points for a variety of states—including temperature, weight, sleep, thirst, and hunger. When the level is off (in either direction, too much or too little), homeostasis will work to correct it. For example, to regulate temperature, you will sweat when you get too hot or shiver when you get too cold. • Stimulus: A stimulus from a change in the environment kicks something out of balance in the body. • Receptor: The receptor reacts to the change by informing the control unit. • Control unit: The control unit then communicates the change needed to bring the body back into balance. • Effector: The effector receives this information and acts on the change that is needed. • Endotherms: Some creatures, known as endotherms or "warm-blooded" animals, accomplish this via internal physiological processes. Birds and mammals (including humans) are endotherms. • Ectotherms: Other creatures are...

The kidneys are essential for cleansing the blood and eliminating urine waste from the body. They also have other important functions that maintain homeostasis in the body including regulating acid-base balance, the concentration of electrolytes, controlling blood pressure, and secreting hormones. Kidney failure causes a very serious and possibly fatal disruption of homeostasis in the body. Complications include weakness, shortness of breath, widespread swelling (edema), metabolic acidosis, and heart arrhythmias. Acid-Base Balance Along with the lungs, the kidneys are the main organs for regulation of pH in the body. They do this by recovering and regenerating bicarbonate (HCO 3 –) from urine and excreting hydrogen ions (H +) into the urine. The kidneys use the enzyme carbonic anhydrase to catalyze reactions involving bicarbonate. This is the same enzyme used in acid-base balance functions in the red blood cells, the stomach, and pancreas. Electrolyte Concentrations Some of the electrolytes the kidney helps to keep in homeostasis are sodium, potassium, chloride, bicarbonate, magnesium, copper, and phosphate. For example, the hormones aldosterone and angiotensin II regulate the reabsorption of sodium from the renal filtrate and the excretion of sodium into the renal collecting tubule, respectively. Blood Pressure- Extracellular Fluid Volume The kidneys don’t directly sense blood pressure, but they act to regulate blood pressure over the long term. They do this via the renin...

3 Cell Structure and Function • Introduction • 3.1 How Cells Are Studied • 3.2 Comparing Prokaryotic and Eukaryotic Cells • 3.3 Eukaryotic Cells • 3.4 The Cell Membrane • 3.5 Passive Transport • 3.6 Active Transport • Key Terms • Chapter Summary • Visual Connection Questions • Review Questions • Critical Thinking Questions • 4 How Cells Obtain Energy • Introduction • 4.1 Energy and Metabolism • 4.2 Glycolysis • 4.3 Citric Acid Cycle and Oxidative Phosphorylation • 4.4 Fermentation • 4.5 Connections to Other Metabolic Pathways • Key Terms • Chapter Summary • Visual Connection Questions • Review Questions • Critical Thinking Questions • 11 Evolution and Its Processes • Introduction • 11.1 Discovering How Populations Change • 11.2 Mechanisms of Evolution • 11.3 Evidence of Evolution • 11.4 Speciation • 11.5 Common Misconceptions about Evolution • Key Terms • Chapter Summary • Visual Connection Questions • Review Questions • Critical Thinking Questions • 15 Diversity of Animals • Introduction • 15.1 Features of the Animal Kingdom • 15.2 Sponges and Cnidarians • 15.3 Flatworms, Nematodes, and Arthropods • 15.4 Mollusks and Annelids • 15.5 Echinoderms and Chordates • 15.6 Vertebrates • Key Terms • Chapter Summary • Visual Connection Questions • Review Questions • Critical Thinking Questions • 16 The Body’s Systems • Introduction • 16.1 Homeostasis and Osmoregulation • 16.2 Digestive System • 16.3 Circulatory and Respiratory Systems • 16.4 Endocrine System • 16.5 Musculoskeletal ...

Learning Objectives By the end of this section, you will be able to: • Describe the role of the kidneys in vitamin D activation • Describe the role of the kidneys in regulating erythropoiesis • Provide specific examples to demonstrate how the urinary system responds to maintain homeostasis in the body • Explain how the urinary system relates to other body systems in maintaining homeostasis • Predict factors or situations affecting the urinary system that could disrupt homeostasis • Predict the types of problems that would occur in the body if the urinary system could not maintain homeostasis All systems of the body are interrelated. A change in one system may affect all other systems in the body, with mild to devastating effects. A failure of urinary continence can be embarrassing and inconvenient, but is not life threatening. The loss of other urinary functions may prove fatal. A failure to synthesize vitamin D is one such example. Vitamin D Synthesis In order for vitamin D to become active, it must undergo a hydroxylation reaction in the kidney, that is, an –OH group must be added to calcidiol to make calcitriol (1,25-dihydroxycholecalciferol). Activated vitamin D is important for absorption of Ca ++ in the digestive tract, its reabsorption in the kidney, and the maintenance of normal serum concentrations of Ca ++ and phosphate. Calcium is vitally important in bone health, muscle contraction, hormone secretion, and neurotransmitter release. Inadequate Ca ++ leads to diso...

Learning Objectives By the end of this section, you will be able to: • Describe the role of the kidneys in vitamin D activation • Describe the role of the kidneys in regulating erythropoiesis • Provide specific examples to demonstrate how the urinary system responds to maintain homeostasis in the body • Explain how the urinary system relates to other body systems in maintaining homeostasis • Predict factors or situations affecting the urinary system that could disrupt homeostasis • Predict the types of problems that would occur in the body if the urinary system could not maintain homeostasis All systems of the body are interrelated. A change in one system may affect all other systems in the body, with mild to devastating effects. A failure of urinary continence can be embarrassing and inconvenient, but is not life threatening. The loss of other urinary functions may prove fatal. A failure to synthesize vitamin D is one such example. Vitamin D Synthesis In order for vitamin D to become active, it must undergo a hydroxylation reaction in the kidney, that is, an –OH group must be added to calcidiol to make calcitriol (1,25-dihydroxycholecalciferol). Activated vitamin D is important for absorption of Ca ++ in the digestive tract, its reabsorption in the kidney, and the maintenance of normal serum concentrations of Ca ++ and phosphate. Calcium is vitally important in bone health, muscle contraction, hormone secretion, and neurotransmitter release. Inadequate Ca ++ leads to di...

\( \newcommand\) • • • • • • • • • • • • • Learning Objectives • Explain how different organ systems relate to one another to maintain homeostasis Each organ system performs specific functions for the body, and each organ system is typically studied independently. However, the organ systems also work together to help the body maintain homeostasis. Water Levels For example, the cardiovascular, urinary, and lymphatic systems all help the body control water balance. The cardiovascular and lymphatic systems transport fluids throughout the body and help sense both solute and water levels and regulate pressure. If the water level gets too high, the urinary system produces more dilute urine (urine with a higher water content) to help eliminate the excess water. If the water level gets too low, more concentrated urine is produced so that water is conserved. Internal Temperatures Similarly, the cardiovascular, integumentary (skin and associated structures), respiratory, and muscular systems work together to help the body maintain a stable internal temperature. If body temperature rises, blood vessels in the skin dilate, allowing more blood to flow near the skin’s surface. This allows heat to dissipate through the skin and into the surrounding air. The skin may also produce sweat if the body gets too hot; when the sweat evaporates, it helps to cool the body. Rapid breathing can also help the body eliminate excess heat. Together, these responses to increased body temperature explain ...

Table of Contents • • • • • • How does the kidney maintain homeostasis? The kidneys maintain homeostasis by controlling the amount of water, ions, and other substances in the blood. Kidneys also secrete hormones that have other homeostatic functions. How does the urinary system help to keep the body in homeostasis? The urinary system maintains blood homeostasis by filtering out excess fluid and other substances from the bloodstream and secreting waste. What are the two basic functions of the kidney that work to maintain homeostasis? The kidneys are essential for cleansing the blood and eliminating urine waste from the body. They also have other important functions that maintain homeostasis in the body including regulating acid-base balance, the concentration of electrolytes, controlling blood pressure, and secreting hormones. What are three ways the kidneys maintain homeostasis? How do the heart and kidneys work together to maintain homeostasis? How do the kidneys and heart work together? The heart pumps blood filled with oxygen through all parts of your body, including the kidneys. The kidneys clean the blood, removing waste products and extra water. Without the kidneys, your blood would have too much waste and water. Do kidneys regulate hormones? Hormones The kidneys secrete a number of hormones, which are important for normal functioning of the body. One such hormone is renin, which keeps blood pressure normal. If blood pressure falls, renin is secreted by the kidneys t...