–2/”>a >DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.0 Transitional//EN” “http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd”>
is the process of maintaining salt and water balance (osmotic balance) across membranes within the body. The fluids inside and surrounding cells are composed of water, electrolytes, and nonelectrolytes. An electrolyte is a compound that dissociates into ions when dissolved in water. A nonelectrolyte, in contrast, does not dissociate into ions in water. The body’s fluids include blood plasma, fluid that exists within cells, and the interstitial fluid that exists in the spaces between cells and Tissues of the body. The membranes of the body (both the membranes around cells and the “membranes” made of cells lining body cavities) are semipermeable membranes. Semipermeable membranes are permeable to certain types of solutes and to water, but typically cell membranes are impermeable to solutes.
The body does not exist in isolation. There is a constant input of water and electrolytes into the system. Excess water, electrolytes, and wastes are transported to the kidneys and excreted, helping to maintain osmotic balance. Insufficient fluid intake results in fluid conservation by the kidneys. Biological systems constantly interact and exchange water and nutrients with the Environment by way of consumption of food and water and through Excretion in the form of sweat, urine, and feces. Without a mechanism to regulate osmotic pressure, or when a disease damages this mechanism, there is a tendency to accumulate toxic waste and water, which can have dire consequences.
Mammalian systems have evolved to regulate not only the overall osmotic pressure across membranes, but also specific concentrations of important electrolytes in the three major fluid compartments: blood plasma, interstitial fluid, and intracellular fluid. Since osmotic pressure is regulated by the movement of water across membranes, the volume of the fluid compartments can also change temporarily. Since blood plasma is one of the fluid components, osmotic pressures have a direct bearing on blood pressure.
Renovascular hypertension
Renovascular hypertension is high blood pressure due to narrowing of the arteries that carry blood to the kidneys. This condition is also called renal artery stenosis.
renal artery stenosis is a narrowing or blockage of the arteries that supply blood to the kidneys. The most common cause of renal artery stenosis is a blockage in the arteries due to high cholesterol. This problem occurs when a sticky, fatty substance called plaque builds up on the inner lining of the arteries, causing a condition known as atherosclerosis. When the arteries that carry blood to your kidneys become narrow, less blood flows to the kidneys. The kidneys mistakenly respond as if your blood pressure is low. As a result, they release HORMONES that tell the body to hold on to more salt and water. This causes your blood pressure to rise.
Kidney Cysts
Simple kidney cysts are abnormal, fluid-filled sacs that form in the kidneys. Simple kidney cysts are different from the cysts that develop when a person has polycystic kidney disease (PKD), which is a genetic disorder. Simple kidney cysts do not enlarge the kidneys, replace their normal structure, or cause reduced kidney function like cysts do in people with PKD.
Simple kidney cysts are more common as people age. An estimated 25 percent of people 40 years of age and 50 percent of people 50 years of age have simple kidney cysts.
The cause of simple kidney cysts is not fully understood. Obstruction of tubules—tiny structures within the kidneys that collect urine—or deficiency of blood supply to the kidneys may play a role. Diverticula—sacs that form on the tubules—may detach and become simple kidney cysts. The role of genetic factors in the development of simple kidney cysts has not been studied.
Urinary incontinence
Urinary incontinence is the involuntary leakage of urine. It means a person urinates when they do not want to. Control over the urinary sphincter is either lost or weakened. Urinary incontinence is a common problem that affects many people.
Urinary incontinence is when a person cannot prevent urine from leaking out. It can be due to Stress factors, such as coughing, it can happen during and after pregnancy, and it is more common with conditions such as obesity.
Urinary tract infection
A urinary tract infection, or UTI, is an infection of the urinary tract. The infection can occur at different points in the urinary tract, including:
Bladder — An infection in the bladder is also called cystitis or a bladder infection. Kidneys — An infection of one or both kidneys is called pyelonephritis or a kidney infection.
Ureters — The tubes that take urine from each kidney to the bladder are rarely the only site of infection.
Urethra — An infection of the tube that empties urine from the bladder to the outside is called urethritis.
Most UTIs are caused by bacteria that enter the urethra and then the bladder. The infection most commonly develops in the bladder, but can spread to the kidneys. Most of the time, your body can get rid of these bacteria. However, certain conditions increase the risk of having UTIs.
The following also increase your chances of developing a UTI:
- Diabetes
- Advanced age and conditions that affect personal care habits (such as Alzheimer disease and delirium)
- Problems emptying the bladder completely
- Having a urinary catheter Bowel incontinence
- Enlarged prostate,
- Narrowed urethra,
- or anything that blocks the flow of urine Kidney stones
Kidney stone
A kidney stone is a hard, crystalline mineral material formed within the kidney or urinary tract. Kidney stones are a common cause of blood in the urine (hematuria) and often severe pain in the abdomen, flank, or groin. Kidney stones are sometimes called renal calculi.
The condition of having kidney stones is termed nephrolithiasis. Having stones at any location in the urinary tract is referred to as urolithiasis, and the term ureterolithiasis is used to refer to stones located in the ureters.
Diabetes Insipidus
Diabetes insipidus is a rare disorder that occurs when a person's kidneys pass an abnormally large volume of urine that is insipid—dilute and odorless. In most people, the kidneys pass about 1 to 2 quarts of urine a day. In people with diabetes insipidus, the kidneys can pass 3 to 20 quarts of urine a day. As a result, a person with diabetes insipidus may feel the need to drink large amounts of liquids.
Diabetes insipidus and diabetes mellitus—which includes both type 1 and type 2 diabetes—are unrelated, although both conditions cause frequent urination and constant thirst. Diabetes mellitus causes high blood glucose, or blood sugar, resulting from the body's inability to use blood glucose for energy. People with diabetes insipidus have normal blood glucose levels; however, their kidneys cannot balance fluid in the body.
,
Osmoregulation is the process by which an organism maintains a stable internal environment despite changes in the external environment. This is important for all organisms, as it allows them to function properly and avoid damage from changes in water concentration.
There are two main types of osmoregulation: osmoconformers and osmoregulators. Osmoconformers allow their internal water concentration to change in response to the external environment. This is a relatively simple process, but it means that osmoconformers are limited to living in environments with a similar water concentration to their own bodies.
Osmoregulators, on the other hand, maintain a constant internal water concentration regardless of the external environment. This is a more complex process, but it allows osmoregulators to live in a wider range of environments.
There are many different mechanisms that organisms use to osmoregulate. Some organisms, such as Plants, can absorb water directly from the environment. Others, such as animals, must drink water or take it in through their food. Some organisms, such as insects, can excrete excess water through their spiracles (small openings on the sides of their bodies). Others, such as mammals, can excrete excess water through their kidneys.
Osmoregulation is an essential process for all organisms. It allows them to maintain a stable internal environment and avoid damage from changes in water concentration. There are many different mechanisms that organisms use to osmoregulate, and the specific mechanism used varies depending on the organism.
Osmoregulation in plants
Plants are constantly taking in water and nutrients from the Soil, and they are also constantly losing water through Transpiration. This means that plants need to be able to regulate their water balance in order to survive.
Plants do this by a process called osmoregulation. Osmoregulation is the process by which plants control the movement of water and solutes (dissolved substances) across their cell membranes.
Plants have a number of mechanisms that they use to osmoregulate. One mechanism is to control the opening and closing of their stomata. Stomata are small pores on the surface of leaves that allow gas exchange to take place. When stomata are open, water vapor can escape from the plant. This helps to reduce the amount of water that the plant loses through transpiration.
Plants also have a number of mechanisms that they use to control the movement of water and solutes across their cell membranes. One mechanism is to use pumps to move ions (charged particles) across the cell membrane. This can create a difference in water potential across the membrane, which drives water into the cell.
Another mechanism that plants use to osmoregulate is to change the concentration of solutes in their cells. This can also create a difference in water potential across the membrane, which drives water into or out of the cell.
Osmoregulation is an essential process for plants. It allows plants to maintain a constant internal environment and avoid damage from changes in water availability.
Osmoregulation in animals
Animals, like plants, need to maintain a constant internal environment. This is especially important for animals that live in environments with extreme temperatures or where water is scarce.
Osmoregulation is the process by which animals control the amount of water and salt in their bodies. Animals do this by a variety of mechanisms, including drinking water, excreting waste, and sweating.
Animals that live in aquatic environments, such as fish, have a different set of challenges than animals that live on land. Fish need to be able to regulate the amount of salt in their bodies, as well as the amount of water. They do this by using a variety of mechanisms, including the gills, the kidneys, and the intestines.
The gills are the organs that fish use to breathe. They are located on the sides of the fish’s head. The gills are covered in a thin layer of mucus, which helps to filter out salt from the water. The kidneys are the organs that fish use to excrete waste. They are located near the spine. The kidneys filter out waste products from the blood and produce urine. The intestines are the organs that fish use to digest food. They are located in the abdomen. The intestines absorb water and nutrients from the food, and they also excrete waste products.
Animals that live on land, such as humans, have a different set of challenges than animals that live in aquatic environments. Humans need to be able to regulate the amount of water in their bodies, as well as the amount of salt. They do this by a variety of mechanisms, including drinking water, sweating, and urinating.
Drinking water is the most important way that humans regulate the amount of water in their bodies. When we drink water, the water is absorbed into the bloodstream and transported to the cells. The cells use the water for a variety of purposes, including Metabolism, digestion, and waste removal.
1. What is homeostasis?
Homeostasis is the maintenance of a relatively stable internal environment despite changes in the external environment.
2. What are the different types of homeostasis?
There are many different types of homeostasis, but some of the most common include:
- Thermoregulation: The maintenance of a constant body temperature.
- Osmoregulation: The maintenance of a constant body fluid balance.
- Acid-base balance: The maintenance of a constant pH level in the blood.
- Blood sugar regulation: The maintenance of a constant blood sugar level.
3. How does the body maintain homeostasis?
The body maintains homeostasis through a variety of mechanisms, including:
- The nervous system: The nervous system sends signals to different parts of the body to help regulate body functions.
- The Endocrine System: The endocrine system produces hormones that help regulate body functions.
- The immune system: The immune system protects the body from infection and disease.
- The Digestive System: The digestive system breaks down food and absorbs nutrients that the body needs to function properly.
- The Excretory System: The excretory system removes waste products from the body.
4. What are some examples of homeostasis in action?
Some examples of homeostasis in action include:
- When you are cold, your body shivers to generate heat.
- When you are hot, you sweat to cool down.
- When you eat a meal, your blood sugar level rises. Your pancreas then releases insulin, which helps your body to use the glucose for energy.
- When you are dehydrated, your kidneys produce more urine to conserve water.
- When you are sick, your immune system fights off the infection.
5. What are some challenges to homeostasis?
Some challenges to homeostasis include:
- Changes in the external environment, such as temperature, humidity, and altitude.
- Illness or injury.
- Stress.
- Aging.
6. How can we overcome challenges to homeostasis?
We can overcome challenges to homeostasis by:
- Maintaining a healthy lifestyle.
- Eating a balanced diet.
- Getting regular exercise.
- Getting enough sleep.
- Managing stress.
- Seeing a doctor when we are sick.
-
Which of the following is not a function of the kidneys?
(A) Excretion of waste products
(B) Regulation of blood pressure
(C) Production of red blood cells
(D) Maintenance of water balance -
The process of filtration of blood in the kidneys is called:
(A) Glomerular filtration
(B) Tubular reabsorption
(C) Tubular secretion
(D) All of the above -
The main function of the loop of Henle is to:
(A) Reabsorb water
(B) Reabsorb sodium
(C) Secrete potassium
(D) All of the above -
The main function of the collecting duct is to:
(A) Reabsorb water
(B) Reabsorb sodium
(C) Secrete potassium
(D) All of the above -
The hormone that regulates water reabsorption in the kidneys is:
(A) Antidiuretic hormone (ADH)
(B) Aldosterone
(C) Atrial natriuretic peptide (ANP)
(D) All of the above -
The hormone that regulates sodium reabsorption in the kidneys is:
(A) Antidiuretic hormone (ADH)
(B) Aldosterone
(C) Atrial natriuretic peptide (ANP)
(D) None of the above -
The hormone that regulates potassium secretion in the kidneys is:
(A) Antidiuretic hormone (ADH)
(B) Aldosterone
(C) Atrial natriuretic peptide (ANP)
(D) None of the above -
The main function of the urinary bladder is to:
(A) Store urine
(B) Transport urine to the urethra
(C) Empty urine from the body
(D) All of the above -
The main function of the urethra is to:
(A) Store urine
(B) Transport urine to the urinary bladder
(C) Empty urine from the body
(D) None of the above -
The Average adult urinates about:
(A) 1-2 liters per day
(B) 2-3 liters per day
(C) 3-4 liters per day
(D) 4-5 liters per day