Chapter 12

Question 1

What are the major roles of water in the body?

Answer 1

It carries nutrients and waste products throughout the body.

Maintains the structure of large molecules such as proteins and glycogen.

Participates in metabolic reactions.

Serves as the solvent for minerals, vitamins, amino acids, glucose, and many other small molecules.

Acts as a lubricant and cushion around joints and inside the eyes, the spinal cord, and in pregnancy, the amniotic sac surrounding the fetus in the womb.

Aids in the regulation of normal body temperature, as the evaporation of sweat from the skin removes excess heat from the body.

Maintains the body’s blood volume.

Question 2

What percentage of your body is water?

Answer 2

60 percent

Question 3

Which nutrient is needed in the greatest amount by the body?

Answer 3

Water

Question 4

Extracellular Fluid

Answer 4

The fluid outside the cells and it accounts for approximately one-third of the body’s water.

Question 5

Intracellular Fluid

Answer 5

Fluid inside the cells, usually high in potassium and phosphate. It accounts for approximately two-thirds of the body’s water.

Question 6

Interstitial Fluid

Answer 6

Fluid that surrounds each cell.

Question 7

Intravascular Fluid

Answer 7

Fluid within the blood vessels.

Question 8

Explain how fluid balance and blood pressure are each regulated in the body, including the hormones and organs involved.

Answer 8

Whenever blood volume or blood pressure falls too low, or whenever the extracellular fluid becomes too concentrated, the hypothalamus signals the pituitary gland to release antidiuretic hormone (ADH) which stimulates the kidneys to reabsorb water. The cells in the kidneys respond to low blood pressure by releasing an enzyme called renin which reabsorb sodium. The. The renin hydrolyzes angiotensinogen (a protein produced by the liver) to angiotensin I until another enzyme converts it to its active form angiotensin II, which is a powerful vasoconstrictor that narrows the diameters of blood vessels, raising blood pressure. Lastly, angiotensin II stimulates the release of the hormone aldosterone from the adrenal glands to signal the kidneys to excrete potassium and retain more sodium to allow water to flow.

Question 9

Oral rehydration therapy (ORT)

Answer 9

A simple solution of sugar, salt, and water taken by mouth to treat dehydration caused by severe diarrhea.

Question 10

Bicarbonate and Carbonic Acid

Answer 10

Protects the body against changes in acidity by acting as buffers.

The lungs control the concentration of carbonic acids by raising or lowering respiration rate.

The kidneys control the concentration of bicarbonate by either reabsorbing or excreting it.

Question 11

Signs of Dehydration

Answer 11

1-2% of Body Weight Loss - Thirst, weakness, fatigue, loss of appetite.

3-4% - Impaired physical performance, dry mouth, flushed skin, apathy.

5-6% - Headache, sleepiness, impaired temperature regulation, increased respiratory rate, difficulty concentrating.

7-10% - Dizziness, loss of balance, collapse, exhaustion.

Question 12

How much water is required by the body each day?

Answer 12

About 15.5 cups (3.7 liters) of fluids a day for men and about 11.5 cups (2.7 liters) of fluids a day for women.

Question 13

How must your fluid requirement be met?

Answer 13

Through water, beverages, and food.

Question 14

What fluids that we drink count towards our daily fluid intake?

Answer 14

Water, lower-fat milk and sugar-free drinks, including tea and coffee, all count.

Question 15

How should your urine look if you are well hydrated?

Answer 15

Pale straw or transparent yellow

Question 16

Give 3 tips/strategies for increasing your water intake.

Answer 16

Replace drinks with water, eat more hydrating foods, and adding flavor by putting fruits in water.

Question 17

Describe the differences between the major and trace minerals.

Answer 17

Major minerals are essential mineral nutrients that the body require in large amounts and trace minerals are require in smaller amounts.

Question 18

Name the major minerals.

Answer 18

Sodium, chloride, potassium, calcium, phosphorus, magnesium, and sulfur.

Question 19

List the factors that affect the bioavailability, absorption, and retention of minerals.

Answer 19

Diet, nutrient concentration, nutritional status, health, and life-stage.

Question 20

Sodium

Answer 20

•Function - Helps maintain normal fluid and electrolyte balance. Also maintain acid-base balance and is essential to nerve impulse transmission and muscle contraction.

•Deficiency symptoms- Headache, confusion, and seizures..

•Toxicity symptoms- hypertension and heart disease.

•Significant sources- Table salt, soy sauce, and processed foods

Question 21

Potassium

Answer 21

•Functions- Same functions as sodium.

•Deficiency symptoms- Irregular heatbeat, muscular weakness, glucose intolerance.

•Toxicity symptoms- Muscular weakness; vomiting; if injected into a vein, can stop the heart.

•Significant sources- All whole foods: meats, milks, fruits, vegetables, grains, legumes.

Question 22

Calcium

Answer 22

•Functions- Mineralization of bones and teeth; involved in muscle contraction and relaxation, nerve functioning, blood clotting, blood pressure.

Deficiency symptoms- Stunted growth in children; bone loss (osteoporosis) in adults.

Toxicity symptoms- Constipation; increased risk of urinary stone formation and kidney dysfunction, interference with absorption of other minerals.

Significant Sources- Milk and milk products, small fish (with bones), calcium-set tofu, leafy greens (broccoli, kale).

Question 23

Phosphorus

Answer 23

•Functions- Part of genetic material in phospholipids; used in energy transfer and in buffer systems that maintain acid-base balance.

Deficiency symptoms- Muscular weakness, bone pain.

Toxicity symptom- Calcification of nonskeletal tissues, particularly the kidneys.

Significant Sources- Protein-rich foods (meat, fish, poultry, eggs, milk, legumes, nuts).

Question 24

Magnesium

Answer 24

•Functions- Bone mineralization; participates in energy metabolism and muscle contraction.

•Deficiency symptoms- Muscle cramps, tetany, seizures.

•Toxicity symptoms- From nonfood sources only; diarrhea, nausea, abdominal cramps; metabolic alkalosis.

•Significant sources- Nuts, legumes, green leafy vegetables, some fish.

Question 25

Compare the roles of minerals in the development of healthy bone tissue and osteoporosis.

Answer 25

Inadequate intake of nutrients important to bone increases the risk for bone loss and subsequent osteoporosis.

Question 26

Factors that reduce the risk of osteoporosis

Answer 26

Eat calcium-rich foods, absorb enough vitamin D, avoid smoking, and limit alcohol consumption.

Question 27

Factors that increase risk for osteoporosis

Answer 27

Lack of calcium and vitamin D, menopause, smoking, alcohol, and low physical activity.

Question 28

Describe nutrition and lifestyle strategies that would reduce your risk for osteoporosis.)

Answer 28

Some nutrition and lifestyle strategies that would reduce the risk of osteoporosis are being more physically active, consuming more vitamin D and calcium rich foods, and to not consume alcohol or smoke.

Question 29

What enzyme is released from the kidney in response to hypotension?

Answer 29

Renin

Question 30

What is the source of the most sodium consumed in the American diet?

Answer 30

Processed foods

Question 31

Which of the following foods contains phytates?

Answer 31

Legumes

Question 32

Which of the following is a result of hypercalcemia?

Answer 32

Secretion of calcitonin from the thyroid gland

Question 33

What percentage of bone loss might occur in the six to eight-year period following menopause?

Answer 33

20 percent

Question 34

At what age does trabecular bone loss become significant for both men and women?

Answer 34

30s