Why is it important that the body is able to expend energy in order to make some transport reactions possible?
The three main types of passive transport mechanisms, those that don't require energy, are simple diffusion, facilitated diffusion, and osmosis. Simple diffusion enables substances to cross cell membranes from a region of higher concentration to a region of lower concentration. Facilitated diffusion also involves the passive movement of a substance down its concentration gradient (high concentration to low concentration) but differs from simple diffusion in that it requires the assistance of a membrane-bound transport protein that escorts materials across cell membranes. However, for the body to function properly, some substances must cross cell membranes against the prevailing concentration gradient, moving from a region of lower concentration to that of a higher concentration. In cells, this uphill journey is accomplished by active transport mechanisms, which require the expenditure of energy as ATP.
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Which of the following statements is not true regarding the health benefits of fiber?
a. Fiber aids in weight management. b. Fiber aids in the management of diabetes. c. Fiber aids in overall health of the gastrointestinal tract. d. Fiber aids in the prevention of osteoporosis.
Mr. Stanley Edward, a 58-year-old African American male, was admitted to the emergency room of the medical center upon being found unconscious in his car in a parking lot and resuscitated. His history was obtained by contacting his daughter. The patient presents with:
• end-stage adenocarcinoma of the gastroestophageal juncture. • chronic malnutrition and significant weight loss × 1 year. Low BMI, loss of muscle, loss of subcutaneous fat, bitemporal wasting. • acute pancreatitis with intractable vomiting. Medical Hx: Hypertension; S/P stroke @ age 56; cataract surgery. Meds: antilipemic medication, antihypertensive medication. Hx: Lifelong chain smoker (2 packs per day); alcohol abuse since his late 20s. Ht: 5'8". Admission Wt: 107 lbs. Usual Wt, 1 year ago: 170 lbs. Social Hx: Lives alone; cooks and shops for himself despite illness. Dietary Hx: Previously followed a low-cholesterol, low-sodium, high-potassium diet. Mr. Edward is not being actively treated for cancer at his request. Plan is to keep Mr. Edward NPO and place a peripheral line for hydration and nutrition support. Mr. Edward's blood glucose level rises to 350 mg/dL. What will the health care team likely do about this? a. nothing; this is acceptable for a patient receiving TPN b. taper off his lipids infusion c. stop his TPN infusion entirely d. infuse insulin with his TPN
Which of the following is not a key nutrient most often lacking in the U.S. diet?
1.Fiber 2.Potassium 3.Calcium 4.Vitamin D 5.Sodium 6.All of these key nutrients are often lacking in the U.S. diet
When broiling or grilling:
a. a marinade must be fully cooked if it is to be used for basting. b. it is acceptable to reuse the plate used to carry the raw poultry to the grill to carry it back to the table after it is cooked, as long it is rinsed in between uses. c. if vegetable sprays are used to prevent sticking, chicken is placed skin side down in a broiler pan and skin side up for grilling over coals. d. it is best to add barbecue sauces at the beginning of the cooking process so that there is ample time for the flavor to absorb into the chicken.