Chapter 7: Proteins

Describe what happens to excess amino acids in the body.

Ammonia (NH3) is converted to urea in the liver. The kidneys excrete urea in urine.

Fred is a lactovegetarian. Which of the following foods does he eat?

Cheese

The ________ is main site of deamination in the body.

Liver

The ________ is the primary site for nonessential amino acid production in humans.

Liver

________ is an essential amino acid.

Lysine

identify foods that a person with celiac disease must avoid

gluten, a group of related proteins in wheat, barley, and rye.

In 2017-2018, protein comprised ________% of an adult American's average daily energy intake.

16

Bethaney is 20 years of age and weighs 50 kg. Based on her body weight, her RDA for protein is ________ grams.

40 (0.8 * kg)

Keegan is 24 years of age and weighs 178 pounds. Based on his body weight, his RDA for protein is about ________ grams.

75 grams (Lbs / 2.2 = KG) (KG*0.8= Grams)

Which of the following foods is a high-protein snack that can replace a snack that contains animal proteins?

8oz of soy milk

Explain the cause of phenylketonuria, and discuss how the condition is treated.

Caused by lack of enzyme that converts the essential amino acid phenylalanine to another compound Critical to provide low-phenylalanine diet to infant with PKU a few days after birth

Explain what causes celiac disease and list three common signs and symptoms of the disease.

Celiac disease is a common inherited condition that results in malabsorption of nutrients from the small intestine. • Abdominal bloating• Chronic diarrhea• Weight loss

Explain how cells make proteins.

Cells assemble the 20 amino acids in specific sequences and lengths according to information provided in DNA.

Explain what happens to proteins as they undergo digestion and absorption in the human digestive tract.

Chemical digestion of protein begins in the stomach: • Hydrochloric acid denatures proteins. • The enzyme pepsin digests proteins into smaller polypeptides. Polypeptides enter the small intestine: • The enzymes trypsin and chymotrypsin break down polypeptides into shorter peptides and individual amino acids.

Recommendations for Protein Intake

Choose lean or low-fat meat and poultry. Trim visible fat from meats. Limit intake of processed meat ("deli meat"). Choose more fish and protein-rich plant protein sources, such as dry beans, split peas, seeds, and nuts.

Explain how using mixtures of foods with complementary proteins can help reduce animal protein intake.

Complementary combinations: • Mixing certain plant foods to provide all essential amino acids without adding animal proteins

Classify an amino acid as essential or nonessential.

Essential Amino Acids:• Cannot be made by the body • Must be supplied by the diet • 9 of the 20 amino acids Nonessential Amino Acids: • Can be made by the body • 11 of the 20 amino acids

Discuss potential health problems that may occur with excessive protein intake.

Excess protein/amino acid intake may lead to dehydration and higher than normal urinary losses of calcium, but this is controversial. Protein-rich foods are high in purines • Body makes uric acid from purines. • High blood uric acid level can contribute to gout. • High uric acid in urine may contribute to kidney stones.

Animal foods such as meat and eggs are almost 100% protein True or false?

False

People can nourish their hair by using shampoo that contains protein. True or false?

False

Registered dietitian nutritionists generally recommend that people with liver or kidney disease take amino acid supplements to increase their protein intake. True or false?

False

Identify chronic diseases associated with processed meat consumption.

High amounts of red or processed meat is associated with increased risk for CVD and some forms of cancer.

Explain the difference between a high-quality protein and a low-quality protein.

High-quality (complete) protein: • Contains all 9 essential amino acids in amounts that support protein deposition in tissues and a child's growth• Most animal products • High-quality protein sources (plants): quinoa and processed soy Low-quality (incomplete) protein: • Lacks or has inadequate amounts of 1 or more of the essential amino acids

Compare the percentage of calories that protein contributes in the typical American diet to the AMDR for protein.

In 2017 to 2018, protein comprised 16% of an adult American's average energy intake for a day. • The AMDR for protein is 10 to 35% of energy.

Explain the cause of a food allergy and list three common signs and symptoms of a food allergy.

Inflammatory response resulting when body's immune system reacts inappropriately to a substance that is typically harmless. • Hives (red raised bumps on skin) • Swollen or itchy lips• Skin flushing

Describe ways people can reduce the amount of meat in their diet without sacrificing protein quality.

Make meals that contain less animal protein and more plant protein. • By mixing plant and animal sources of protein you extend the quality of protein in the meal. • Include more legumes in meals (for example, chili, bean or lentil soups, and beans with rice) while reducing meat content.

Identify food groups that contribute most of the protein in the typical American diet.

Meat, fish, poultry, dairy, and eggs provide most of the protein (70 to 85%) in Americans' diets.

Explain the concept of nitrogen balance, and identify conditions in which the body is a state of positive or negative nitrogen balance.

Nitrogen balance (equilibrium): Nitrogen gain equals nitrogen loss • Positive nitrogen balance: Body retains more nitrogen than it loses • Negative nitrogen balance: Body loses more nitrogen than it retains

When combined, which of the following groups of foods forms a complementary protein dish?

Peanuts, rice, and cashews

Discuss pros and cons of vegetarian diets.

Pros Reduced disease risk May boost longevity Increased food variety Improved weight control Offers complete nutrition Reduced food costs Friendly environmental impact Ethical treatment of animals Con Possible nutrient deficiencies Fewer food choices Reduced satiety Less convenient Not always healthy Exposure to chemicals

Explain why protein-energy malnutrition is a serious nutritional state, especially for young children.

Protein-energy malnutrition (PEM) results when the diet lacks energy and high-quality protein. It can cause Marasmic kwashiorkor(• Inadequate energy and protein intake• Muscle wasting and edema) and Marasmus (starvation)

Identify foods that are most likely to cause food allergies in vulnerable people

Protein-rich foods:• Cow's milk• Eggs• Peanuts• Wheat• Soybeans• Fish & shellfish Nonproteins:• Food dyes• Naturally present sulfites or sulfites added to:• Wine• Potatoes• Shrimp

Identify the basic structural unit of proteins and its components.

Proteins are made of smaller units called amino acids. Human proteins can have 20 different amino acids. Each amino acid is composed of: 1) The amino or nitrogen-containing group 2) R-group — varies with each amino acid 3) Acid group - acid portion

Which of the following foods is a good source of high-quality protein?

Soy milk

List at least three amino acids that are often "limiting amino acids" in plant foods.

The most limiting amino acid in cereals is lysine, followed by threonine, methionine, and valine.

List the primary function of proteins in the body.

They are essential for the cells to grow and reproduce as well as maintain other functions. Proteins perform a large number of roles inside the body, including cell signaling, immune responses, transport of molecules from one location to another, and responding to stimuli.

Americans typically consume more protein from animal sources than from plant foods. True or false?

True

Foods made from soybeans can be sources of high-quality protein. True or false?

True

Describe different forms of vegetarianism.

Vegetarian - No Meat Vegan- No Animal Products Lacto- Vegetarian - No Meat, Eggs Pescatarian - Vegetarian/ Only Seafood Ovo-Vegetarian - Allows Eggs/ No Dairy Raw Vegan- Plant- Based, Raw, Unprocessed Flexitarian - Vegan/Vegetarian (Allows Meat Every Once in a While)

Two-month-old Deanna is not growing normally. After Deanna underwent numerous tests, her physicians determined that she was born with a condition in which fat deposits form in cells that are not designed to store fat. The fat deposits eventually kill the cells. Her older brother died as a result of the same disorder when he was 8 months of age. Based on this information, Deanna has ________.

defective DNA

The Nutrition Facts panel on a food label ________.

does not provide information about the amount of protein in a serving of the food

An amino acid does not contain a(an) ________.

fatty acid

A team of food scientists wants to develop a formula diet for newborns that is a nutritionally complete food that replaces human milk. To support normal infant development, the formula must have all of the following ingredients, except ________.

homocysteine

Which of the following foods are legumes?

peanuts

Identify foods that are rich sources of high-quality proteins.

• Foods from animal sources typically have more protein than foods from plants • Seeds, tree nuts, and legumes supply more protein/serving than fruit or the edible leaves, roots, flowers, and stems of vegetables • Legumes are plants that produce seed pods with a single row of seeds, such as soybeans, lentils, beans, peanuts, and peas.

Distinguish between nutrigenetics and nutrigenomics.

• Nutrigenetics: the study of how a person's genetic makeup affects the way his or her body responds to food• Nutrigenomics: the study of how nutrients and other food components can affect a person's genetic expression (protein synthesis)

Discuss practical ways to save money when purchasing food.

• Use unit pricing to compare costs of similar packaged products. • Be wary of appealing offers that are not true bargains. • Compare net weights of packages to determine the best value. • Compare unit prices of pre portioned snack foods • Use coupons when purchasing brand-name items.