Food And Nutrition 3rd Edition - Chapter 21 Testbank

1. This organ plays a major role in maintaining the volume and osmotic strength of body fluids:

Lungs

Kidneys

Liver

Gut

Pituitary gland

The kidneys play a major role in maintaining the volume and osmotic strength of body fluids. They regulate the amount of water and electrolytes in the body by filtering waste products and excess fluid from the blood, which is then excreted as urine. The kidneys also help in maintaining the balance of ions, such as sodium, potassium, and calcium, in the body. Additionally, they produce hormones that regulate blood pressure and stimulate the production of red blood cells. Therefore, the kidneys are crucial in maintaining the overall fluid balance and homeostasis in the body.

Explanation

The kidneys play a major role in maintaining the volume and osmotic strength of body fluids. They regulate the amount of water and electrolytes in the body by filtering waste products and excess fluid from the blood, which is then excreted as urine. The kidneys also help in maintaining the balance of ions, such as sodium, potassium, and calcium, in the body. Additionally, they produce hormones that regulate blood pressure and stimulate the production of red blood cells. Therefore, the kidneys are crucial in maintaining the overall fluid balance and homeostasis in the body.

2. Which of the following is a function of water in the human body?

A medium for biological reactions

A component of all body cells

A transport medium for nutrients and waste

Body temperature regulation

All of the above

Water is a crucial component in the human body and serves multiple functions. It acts as a medium for biological reactions, allowing chemical reactions to occur within cells. Water is also present in all body cells, providing structure and support. Additionally, it serves as a transport medium, carrying nutrients to cells and removing waste products. Lastly, water plays a role in regulating body temperature, helping to maintain a stable internal environment. Therefore, all of the given options are correct as they describe different functions of water in the human body.

Explanation

Water is a crucial component in the human body and serves multiple functions. It acts as a medium for biological reactions, allowing chemical reactions to occur within cells. Water is also present in all body cells, providing structure and support. Additionally, it serves as a transport medium, carrying nutrients to cells and removing waste products. Lastly, water plays a role in regulating body temperature, helping to maintain a stable internal environment. Therefore, all of the given options are correct as they describe different functions of water in the human body.

3. Dehydration can have severe physiological consequences in ___________ and can be caused by __________________.

Infants, severe diarrhoea and vomiting

Elderly, controlled diabetes

Athletes, perspiration and adequate fluid

All of the above

None of the above

Dehydration can have severe physiological consequences in infants due to severe diarrhoea and vomiting. Infants have a smaller body mass and are more vulnerable to fluid loss. Severe diarrhoea and vomiting can lead to significant fluid loss, which can cause dehydration and its associated consequences.

Explanation

Dehydration can have severe physiological consequences in infants due to severe diarrhoea and vomiting. Infants have a smaller body mass and are more vulnerable to fluid loss. Severe diarrhoea and vomiting can lead to significant fluid loss, which can cause dehydration and its associated consequences.

4. Most body fluids contain concentrations of electrolytes which maintain an osmolarity of:

200 mOsm/L

260 mOsm/L

300 mOsm/L

360 mOsm/L

400 mOsm/L

Most body fluids have an osmolarity of 300 mOsm/L. Osmolarity refers to the concentration of solutes in a solution, and in the case of body fluids, electrolytes play a crucial role in maintaining this balance. An osmolarity of 300 mOsm/L ensures that the body fluids are in equilibrium and are able to perform their various functions properly. Deviations from this osmolarity can lead to imbalances in the body, affecting processes such as cell function, fluid balance, and nerve signaling.

Explanation

Most body fluids have an osmolarity of 300 mOsm/L. Osmolarity refers to the concentration of solutes in a solution, and in the case of body fluids, electrolytes play a crucial role in maintaining this balance. An osmolarity of 300 mOsm/L ensures that the body fluids are in equilibrium and are able to perform their various functions properly. Deviations from this osmolarity can lead to imbalances in the body, affecting processes such as cell function, fluid balance, and nerve signaling.

5. The osmotic gradient in body fluids is mostly due to ions of:

Sodium

Potassium

Chloride

Phosphate

All of the above

The osmotic gradient in body fluids is mostly due to ions of sodium, potassium, chloride, and phosphate. These ions play a crucial role in maintaining the balance of fluids and electrolytes in the body. Sodium and chloride are the primary ions responsible for osmotic pressure in extracellular fluids, while potassium and phosphate contribute to osmotic pressure in intracellular fluids. Therefore, all of the above ions contribute to the osmotic gradient in body fluids.

Explanation

The osmotic gradient in body fluids is mostly due to ions of sodium, potassium, chloride, and phosphate. These ions play a crucial role in maintaining the balance of fluids and electrolytes in the body. Sodium and chloride are the primary ions responsible for osmotic pressure in extracellular fluids, while potassium and phosphate contribute to osmotic pressure in intracellular fluids. Therefore, all of the above ions contribute to the osmotic gradient in body fluids.

6. Insensible water loss refers to:

Losses through skin and lungs

Losses through urine and faeces

Negligible and insignificant losses occurring every day

Losses by athletes during exercise

Unexplained water losses

Insensible water loss refers to the losses of water that occur through the skin and lungs without being noticed or perceived. These losses are not related to urine, feces, or exercise, but rather occur continuously as a result of normal bodily functions. The skin and lungs are constantly involved in the process of water vaporization, leading to insensible water loss. This explanation clarifies that insensible water loss specifically refers to the losses through the skin and lungs, distinguishing it from other forms of water loss.

Explanation

Insensible water loss refers to the losses of water that occur through the skin and lungs without being noticed or perceived. These losses are not related to urine, feces, or exercise, but rather occur continuously as a result of normal bodily functions. The skin and lungs are constantly involved in the process of water vaporization, leading to insensible water loss. This explanation clarifies that insensible water loss specifically refers to the losses through the skin and lungs, distinguishing it from other forms of water loss.

7. Death may result from losses of body water greater than:

2.5%

5%

10%

20%

25%

not-available-via-ai

Explanation

not-available-via-ai

8. The total body water content of the average male adult is:

50%

60%

70%

80%

90%

The correct answer is 60%. This is because the total body water content of the average male adult is approximately 60% of their total body weight. This water is distributed throughout the body in various compartments, including intracellular fluid (inside cells) and extracellular fluid (outside cells). Maintaining proper hydration is important for overall health and bodily functions.

Explanation

The correct answer is 60%. This is because the total body water content of the average male adult is approximately 60% of their total body weight. This water is distributed throughout the body in various compartments, including intracellular fluid (inside cells) and extracellular fluid (outside cells). Maintaining proper hydration is important for overall health and bodily functions.

9. Solid foods provide approximately ___ of a healthy individual's daily water intake.

5%

10%

20%

30%

60%

Solid foods provide approximately 30% of a healthy individual's daily water intake. While it is commonly known that drinking water is important for staying hydrated, solid foods also contribute to our overall water intake. Many fruits and vegetables, for example, have high water content and can help keep us hydrated. Therefore, it is recommended to consume a balanced diet that includes a variety of solid foods to maintain adequate hydration levels.

Explanation

Solid foods provide approximately 30% of a healthy individual's daily water intake. While it is commonly known that drinking water is important for staying hydrated, solid foods also contribute to our overall water intake. Many fruits and vegetables, for example, have high water content and can help keep us hydrated. Therefore, it is recommended to consume a balanced diet that includes a variety of solid foods to maintain adequate hydration levels.

10. To conserve body water, the human body is capable of producing urine that has an osmolarity ________ than blood plasma.

5 times weaker

10 times weaker

2 times greater

5 times greater

10 times greater

The human body produces urine with an osmolarity that is 5 times greater than blood plasma in order to conserve body water. This means that the concentration of solutes in the urine is higher than in the blood plasma, allowing the body to excrete excess water while retaining important solutes. This helps to maintain the body's fluid balance and prevent dehydration.

Explanation

The human body produces urine with an osmolarity that is 5 times greater than blood plasma in order to conserve body water. This means that the concentration of solutes in the urine is higher than in the blood plasma, allowing the body to excrete excess water while retaining important solutes. This helps to maintain the body's fluid balance and prevent dehydration.