Anatomy And Physiology Questions - Fluid, Electrolyte And Acid-base Homeostasis

Dehydration is the correct answer because it refers to a condition where the body loses more water than it gains. The given explanation states that when water loss exceeds water gain, dehydration occurs. This can happen due to various reasons such as excessive sweating, inadequate fluid intake, or certain medical conditions. Dehydration can lead to symptoms like thirst, dry mouth, fatigue, dizziness, and in severe cases, it can be life-threatening. Therefore, dehydration is the most appropriate answer based on the given explanation.

Acidosis is a condition characterized by a blood pH below 7.35. It occurs when there is an excess of acid or a decrease in bicarbonate levels in the blood. This imbalance can be caused by various factors such as metabolic disorders, respiratory problems, or kidney dysfunction. Acidosis can lead to symptoms like confusion, fatigue, and shortness of breath. Treatment usually involves addressing the underlying cause and restoring the acid-base balance through medication or other interventions.

Aldosterone is a hormone produced by the adrenal glands that plays a crucial role in regulating the sodium levels in the blood. It acts on the kidneys, promoting the reabsorption of sodium and the excretion of potassium, thereby increasing the concentration of sodium in the blood. This hormone helps maintain the balance of electrolytes in the body and regulates blood pressure. Insulin, renin, Krebs cycle, and glucagon do not directly control sodium levels in the blood, making aldosterone the correct answer.

PTH (parathyroid hormone), calcitriol (active form of vitamin D), and calcitonin are the main regulators of calcium in the blood. PTH increases blood calcium levels by stimulating the release of calcium from bones and reducing calcium excretion by the kidneys. Calcitriol promotes calcium absorption from the intestines. Calcitonin, on the other hand, decreases blood calcium levels by inhibiting bone breakdown and increasing calcium excretion by the kidneys. Together, these hormones maintain the appropriate levels of calcium in the blood, which is crucial for various physiological processes such as muscle contraction, nerve function, and bone health.

Electrolytes in the body serve multiple functions. They help in controlling osmosis between compartments by maintaining the balance of water and ions. Additionally, electrolytes play a crucial role in maintaining the acid-base balance, ensuring that the pH levels in the body remain stable. They also carry electrical currents, which are essential for nerve impulses and muscle contractions. Furthermore, electrolytes can serve as cofactors, assisting in various enzymatic reactions. Therefore, all of the given options - controlling osmosis, maintaining acid-base balance, carrying electrical currents, and serving as cofactors - are functions of electrolytes in the body.

ADH, or antidiuretic hormone, is the major hormone that regulates water loss in the body. It is produced by the hypothalamus and released by the pituitary gland in response to high blood osmolality or low blood volume. ADH acts on the kidneys to increase water reabsorption, reducing the amount of water lost in urine and helping to maintain water balance in the body.

In extracellular fluid, the most abundant cation is sodium. This is because sodium plays a crucial role in maintaining the balance of fluids in the body and is involved in various physiological processes such as nerve impulse transmission, muscle contraction, and regulation of blood pressure. Sodium is actively pumped out of cells and is primarily found in the extracellular fluid, making it the most abundant cation in this fluid compartment.

Antidiuretic hormone is used to promote water reabsorption by the kidneys. It does this by acting on the collecting ducts in the kidneys, increasing their permeability to water. This allows more water to be reabsorbed back into the bloodstream, reducing the amount of water excreted in urine. This hormone is released by the pituitary gland in response to low blood volume or high blood osmolality, and its main function is to regulate water balance in the body.

Interstitial fluid is the fluid that surrounds and fills the spaces between cells in the body. It is a major component of the extracellular fluid, which refers to all the fluid outside of cells. The interstitial fluid plays a crucial role in delivering nutrients and removing waste products from cells. It also helps in maintaining the balance of electrolytes and other substances in the body. Therefore, it is correct to say that 80% of the extracellular fluid is interstitial fluid.

Water is the largest single component of the human body because it makes up about 60% of our total body weight. It is essential for various bodily functions such as regulating body temperature, transporting nutrients and oxygen to cells, lubricating joints, and removing waste products. Additionally, water is present in every cell, tissue, and organ of the body, making it a vital component for overall health and well-being.

Potassium is the most abundant cation in intracellular fluid. Cations are positively charged ions, and they play a crucial role in various cellular processes. Potassium is particularly important for maintaining the cell's electrical potential, regulating fluid balance, and facilitating nerve and muscle cell function. It is actively transported into cells and helps maintain the cell's osmotic balance. Sodium, chloride, phosphate, and bicarbonate are also important ions in the body, but they are more abundant in extracellular fluid rather than intracellular fluid.

Intracellular fluid refers to the fluid inside the cells of the body. It accounts for approximately 66% of the total volume of body fluid. This means that the majority of the fluid in our bodies is contained within our cells, while the remaining fluid is found outside the cells in the extracellular fluid.

Buffer systems, exhaling carbon dioxide, and excretion by the kidneys are all ways to eliminate H+ from the body. Buffer systems, such as the bicarbonate buffer system, help maintain the pH balance in the body by binding with excess H+ ions. Exhaling carbon dioxide helps remove carbonic acid, which is formed when CO2 combines with water, from the body. The kidneys play a crucial role in maintaining acid-base balance by filtering and excreting excess H+ ions in urine. Overall, these mechanisms help regulate the body's pH levels and prevent the accumulation of acidic substances.

Vomiting is the most common cause of metabolic alkalosis. When a person vomits, they lose stomach acid, leading to a decrease in hydrogen ion concentration in the body. This loss of acid disrupts the acid-base balance, causing an increase in blood pH and resulting in alkalosis. Other causes of metabolic alkalosis include excessive use of antacids, diuretic use, and certain medical conditions such as Cushing's syndrome or Conn's syndrome. However, among the options given, vomiting is the most common cause of metabolic alkalosis.

Aldosterone is a hormone that is released by the adrenal glands in response to low blood pressure or low blood volume. It acts on the kidneys to promote the reabsorption of sodium (Na+), which in turn leads to water reabsorption and increased blood volume. This helps to increase blood pressure and maintain fluid balance in the body. Therefore, aldosterone is used to promote Na+ reabsorption by the kidneys.

The correct answer suggests that even though there is partial compensation, the systemic arterial pH is still lower than the normal range of 7.35. This means that the body's attempt to regulate the pH levels is not fully effective, and the pH remains below the desired level.

Calcium phosphate salt is the correct answer because it is the primary form in which phosphate is stored in the body. Phosphate is an essential mineral that plays a crucial role in various biological processes, including bone formation, energy production, and cell signaling. The majority of phosphate is found in the form of calcium phosphate salt, which provides structural support to bones and teeth. It also acts as a reservoir for phosphate ions, which can be released into the bloodstream when needed for other physiological functions.

During cellular respiration, electrons are accepted by oxygen to form water as a byproduct. This water is known as metabolic water, which is produced within the cells as a result of the metabolic process. It plays a crucial role in maintaining hydration and regulating various physiological functions in the body.

Water intoxication occurs when there is a dilution of body fluids and a decrease in the osmolarity of interstitial fluids. This means that the concentration of solutes in the body fluids becomes too low, leading to an imbalance in the electrolytes and water levels. This can happen when a person drinks excessive amounts of water, overwhelming the body's ability to eliminate it, or when there is a decrease in the intake of solutes, such as electrolytes. As a result, water moves from the intracellular fluid (ICF) to the extracellular fluid (ECF) through osmosis, causing the cells to swell and leading to symptoms of water intoxication.

Chloride is the most abundant anion in extracellular fluid. It is an essential electrolyte that plays a crucial role in maintaining fluid balance, regulating pH levels, and transmitting nerve impulses. Chloride ions are primarily found in the form of sodium chloride (table salt) in the extracellular fluid. They help maintain the osmotic pressure and acid-base balance in the body, ensuring proper cell function and overall homeostasis.

Metabolic acidosis occurs when there is an excess of acid or a loss of bicarbonate in the body, leading to a decrease in blood bicarbonate levels. This can be caused by conditions such as kidney disease, diabetes, or severe diarrhea. The imbalance in systemic arterial blood bicarbonate levels dropping below 22mEq/litre indicates metabolic acidosis.

Inadequate exhalation of carbon dioxide can cause blood pH to drop because carbon dioxide is an acidic waste product that is eliminated from the body through exhalation. When there is insufficient exhalation of carbon dioxide, it accumulates in the bloodstream and reacts with water to form carbonic acid. This increases the acidity of the blood, leading to a drop in pH.

Calcium is the most abundant mineral in the body because it plays a crucial role in maintaining the health of bones and teeth. It is also essential for proper muscle function, nerve transmission, and blood clotting. Additionally, calcium is involved in various cellular processes and helps regulate enzyme activity. The body tightly regulates calcium levels to ensure optimal functioning, and any imbalance can lead to health issues such as osteoporosis or muscle cramps. Therefore, the abundance and importance of calcium make it the correct answer.

Respiratory acidosis occurs when there is an imbalance in the body's acid-base balance due to elevated levels of carbon dioxide in the arterial blood. This can happen when there is a decrease in ventilation or an increase in carbon dioxide production. The excess carbon dioxide leads to an increase in hydrogen ion concentration, resulting in a decrease in blood pH and an acidic environment. Therefore, the given statement suggests that the correct answer is respiratory acidosis.

Bradycardia is not a symptom of hyponatremia. Hyponatremia is a condition characterized by low levels of sodium in the blood. Symptoms of hyponatremia typically include confusion, muscular weakness, hypotension (low blood pressure), and tachycardia (rapid heart rate). However, bradycardia refers to a slow heart rate, which is not typically associated with hyponatremia.

Hyperkalaemia refers to high levels of potassium in the blood. While the elderly may be susceptible to fluid and electrolyte disorders such as dehydration, hypernataemia, hyponatraemia, hypokalaemia, and acidosis, hyperkalaemia is not typically caused by increased dietary intake. Instead, it is more commonly caused by impaired kidney function or certain medications.

Natriuresis refers to the excretion of sodium (Na+) in the urine. It is a physiological process that occurs when there is an increase in the excretion of sodium by the kidneys. This helps to regulate the body's fluid balance and blood pressure. The given options do not accurately describe natriuresis, hence the correct answer is "None of the above".

When blood pressure decreases, the body's response is to increase vasoconstriction in order to constrict the blood vessels and maintain blood pressure. This helps to redirect blood flow to vital organs. Therefore, the correct answer is that decreasing blood pressure will NOT cause increased vasoconstriction.

In intracellular fluid, the most abundant anion is phosphate. Phosphate ions are essential for various cellular processes, including energy metabolism, DNA synthesis, and cellular signaling. They play a crucial role in maintaining the pH balance and regulating enzyme activity within the cell. Additionally, phosphate ions are involved in the formation and stability of ATP, the primary energy currency of the cell. Therefore, the high concentration of phosphate ions in the intracellular fluid is necessary for proper cellular function.

Urinary salt loss is the main factor that determines body fluid volume. When salt is excreted through urine, it leads to a decrease in body fluid volume. This is because salt attracts water, so when there is a loss of salt, there is also a loss of water. This loss of water affects the overall fluid balance in the body, leading to a decrease in body fluid volume. Therefore, urinary salt loss plays a crucial role in determining the body's fluid levels.

The breathing rate of an infant causes greater water loss from the lungs. Infants have a higher breathing rate compared to adults, which leads to increased evaporation of water from the lungs. This is because the higher respiratory rate results in more air passing through the lungs, causing more water to be lost through exhalation.

The chloride shift refers to the movement of chloride ions from the plasma to the red blood cells (RBCs) and bicarbonate ions from the RBCs to the plasma. This occurs in response to changes in carbon dioxide levels in the blood. When carbon dioxide levels increase, carbonic acid is formed, which dissociates into bicarbonate ions and hydrogen ions. The bicarbonate ions are then transported out of the RBCs into the plasma in exchange for chloride ions, maintaining the electrochemical balance. This shift helps to regulate pH and maintain homeostasis in the blood.

The rate of fluid intake and output is 7 times higher in an infant than in an adult. This is because infants have a higher metabolic rate and higher water requirements compared to adults. Infants have a larger surface area to body weight ratio, which leads to increased water loss through the skin. Additionally, infants have immature kidneys and higher urine output, contributing to the higher fluid intake and output rate.

A decline in angiotensin II levels does not result in increased calcium reabsorption. Angiotensin II is a hormone that promotes the reabsorption of sodium and water by the kidneys, which in turn leads to increased blood volume and blood pressure. It also stimulates the release of aldosterone, which promotes the reabsorption of sodium and the excretion of potassium. However, angiotensin II does not directly affect calcium reabsorption in the kidneys. Therefore, a decline in angiotensin II levels would not cause an increase in calcium reabsorption.

Metabolic reactions can produce nonvolatile acids, which are acids that cannot be easily eliminated from the body through respiration. These acids are typically generated as byproducts of various metabolic processes, such as the breakdown of proteins and fats. Nonvolatile acids can accumulate in the body and contribute to the body's overall acid-base balance. In contrast, volatile acids can be eliminated through respiration, while hydrogen ions, bicarbonate ions, and calcium ions are not specifically mentioned as products of metabolic reactions in the given options.