Food and Nutrition - Exam 3

Where in the body can vitamins A, D, E, and K be stored?

Adipose tissue

Vitamin D...

All of the above: can be synthesized in the skin, synthesis can be blocked by sunscreens, good sources are found in fatty fish and fortified foods, activated in the kidneys and liver

Vitamin A deficiency:

All of the answers are correct... compromises the ability to see in low light, results in keratinization of epithelial cells, increases the risk of death from infectious disease in children, is the leading cause of preventable blindness in children worldwide.

What is a peptide? Peptide bond?

Amino acids are linked together by peptide bonds to form proteins -Dipeptides: 2 amino acids -Tripeptides: 3 amino acids -Polypeptides: many amino acids

What are proteins made of?

Amino acids are the building blocks of proteins

Which is NOT a function of vitamin D?

Antioxidant

Characteristics of vitamins include all of the following except they:

Are incorporated into the structure of cells

How and in what form is protein used for energy? Excreted?

Before a protein can be used for energy, the amino group must be removed -Liver converts ammonia to urea -Kidney excretes urea -Remaining carbon skeleton is made into energy, glucose, or fat

How are proteins digested and absorbed?

Begins in the stomach and is completed within the mucosal cells lining the small intestine

Vitamin K is required for:

Blood clotting

Vitamin D regulates the concentration of what mineral in blood?

Calcium

Nonessential amino acids:

Can be manufactured in the body

What is an essential amino acid?

Cannot be obtained by the body, do it must be obtained through diet

The recommended intake of what nutrient is higher in those following a vegan diet?

Iron

Vitamin A Deficiency:

Is primary cause of blindness in children worldwide

High-protein diets are associated with low risk of:

Kwashiorkor

What happens when you consume too much protein? Too little?

Kwashiorkor and Edema (swollen belly)

What are incomplete proteins?

Lack one or more essential amino acids such as grains, nuts, seeds, green peas, and legumes

What distinguishes one protein from another?

Each protein has a unique sequence and type of amino acids

The Spanish research participants who ate the Mediterranean-like diet were told to:

Eat more nuts

Amino acids that the body cannot produce and thus must be obtained from foods are ___ amino acids

Essential

Plant-based proteins are usually complete proteins... true or false?

False

What are free radicals and their effects?

Free radical oxidation is capable of altering DNA and establishing cell membranes - The body has a defense system of antioxidants to stop them

The overall shape of a protein molecule determines its:

Function

The shape of a protein is a determinant of its _______ in the body.

Function

Protein is synthesized by linking different amino acids together by ___ bonds into a chain

Peptide

Although not considered essential nutrients, ___ are compounds that are found in plant foods that are physiologically active and beneficial to human health

Phytochemicals

The majority of dietary phytochemicals are part of what class of chemical compounds?

Polyphenols

Protein turnover...

Proteins are constantly being broken down and reassembled in this process

Phytochemicals:

Reduce the risk of cancer and reduce the risk of cardiovascular disease (a and b only)

___ is a performed Vitamin A source

Retinol

Functions of protein do NOT include:

Serving as a store of excess amino acids

Denaturing proteins change their:

Shape

What are the functions/purposes of protein in the body?

Structural material, growth and repair, energy source, critical functions

Amino acids can be used to:

Synthesize glucose or fatty acids (a and b)

You read on a food label that tocopherols have been added. What vitamin has this food been fortified with?

Vitamin E

A supplement of which vitamin is given to newborn babies at birth?

Vitamin K

The Recommended Dietary Allowances (RDA) for vitamin D:

are established based on minimal sun exposure.

Characteristics of vitamins include all of the following, EXCEPT they:

are incorporated into the structure of cells

Each of the following food choices is a source of complete proteins, EXCEPT:

black beans

Vitamin K has a key role in:

blood clotting

Which of the following is the BEST food source of vitamin K?

brussel sprouts

Marilyn follows a vegan diet, so which of the following foods would she avoid?

butter

The type of phytochemicals responsible for the yellow, orange, and red colors of fruits and vegetables are:

carotenoids

All of the following are characteristics of vitamin E as an antioxidant, EXCEPT that it:

dramatically reduces the risks of heart disease and cancer.

Possible toxicity from vitamins is MOST likely to occur with consuming:

fortified foods and dietary supplements

Marasmus:

is characterized by deficiency in most nutrients, including protein

All of the following are TRUE regarding vitamin D, EXCEPT:

its synthesis in the body is not diminished by use of sunscreens.

Pete is a quasi-vegetarian, so he includes all of the following in his diet, EXCEPT:

lean beef

Based on several current studies, organic foods do not differ significantly from nonorganic in:

nutrient content

During which stage of cancer development does the body lose control over the mutated cells allowing metastasis to other tissues?

progression

Nick lifts weights and takes a daily protein supplement in addition to his 30% protein weight-maintenance diet. Taking the protein supplement:

provides additional calories that can contribute to fat stores and will increase his athletic performance. (both b and c)

Inactive, precursor forms of vitamins are termed:

provitamins

Vegetarians that emphasize whole plant foods tend to have higher intakes of all of the following, EXCEPT:

riboflavin

Vitamins are classified according to their:

solubility

Characteristics of the polyphenols include all of the following, EXCEPT:

they are found in salmon and other cold water fish

All of the following are true about complementary protein foods, EXCEPT:

they must be consumed at the same meal or snack to support protein synthesis

All of the following are TRUE regarding carotenoids, EXCEPT:

they supply approximately two-thirds of vitamin A in the U.S. diet

Jason follows a vegan diet and avoids all animal foods. He consumes a wide variety of vegetables, fruits, grains, beans, and other whole plant-based foods. Despite his nutrient-rich diet, supplementation or use of foods fortified with ____________ is recommended.

vitamin B12

The fat-soluble vitamin that is LEAST likely to be toxic when consumed in amounts above recommended intake levels is:

vitamin E.

Vitamin E...

- Best sources are in plants, nuts, and some oils - Healthy immune function - Deficiency: preterm infants, smokers, low fat diets

Vitamin K...

- Blood clotting - Much produced by intestinal bacteria - Deficiency: requires fat for absorption

Vitamin D...

- Can be produced in the skin from cholesterol and exposure to UV light - Activated in the kidneys and liver - Fish - Acts as a hormone

What is a Mediterranean Diet? Is it good or bad?

- Plant based diet - Lowers heart problems and heart-related death

Health benefits of plant based diets?

- Reduce the risk of cancer - Lower blood cholesterol levels - Lower LDL levels - Lower blood pressure - Reduced cardiovascular risk

Vitamin A...

- Retinoid compounds - Exist only in animal products - Vision: 1/3 of children suffer from deficiency - Consuming too much can result in hypervitaminosis A

How much protein do we need?

.8 g/kg of body weight for adults

The Institute of Medicine has established that a safe range of protein intake is:

10% to 35% total calories

Iron found in plant foods (non-heme iron) is lower in bioavailability than the heme iron found in animal foods. Thus, the U.S. Dietary Reference Intake of non-heme iron is _________ higher for vegetarians than the iron recommendation for nonvegetarians.

80%

How many different amino acids must be supplied in our diet?

9

There are 20 amino acids present in proteins; of these ______ are considered essential and are ______ considered nonessential amino acids

9; 11

What are complementary proteins?

Combine two incomplete proteins to make complete protein such as grains, legumes, seeds, and nuts

What are complete proteins?

Contain all nine essential amino acids such as milk, yogurt, cheese, meat, poultry, fish, eggs

During absorption, the process of breaking down peptide chains is facilitated by:

D. stomach acid

Which of the following foods would contain essentially no phytochemicals?

Milk

In a typical Mediterranean diet, more than half of the fat calories are from:

Monounsaturated fat

Like carbohydrates and fat, protein is composed of carbon, hydrogen, and oxygen. Protein differs in that it also contains:

Nitrogen

The body synthesizes 11 out of 20 amino acids. These 11 amino acids are known as:

Nonessential

Which group would not be at risk for vitamin D deficiency?

Occasional sunscreen users

Which food is a poor source of iron?

Oranges

Denaturing of proteins occur in:

The stomach

What is not a characteristic of vitamins?

They provide energy

What is the two step process proteins are synthesized in?

Transcription and Translation

The second step of protein synthesis in which the order of amino acids added to the growing protein chain is read from (or dictated by) the information in the mRNA is termed:

Translation

Bioavailability of carotenoids is higher in cooked chopped carrots than raw carrots... true or false?

True

Fat-soluble vitamins, in comparison to water soluble vitamins, can lead to toxicity when stored in tissue...true or false?

True

Out of all three macronutrients, proteins have the most numerous functions... true or false?

True

Consuming which nutrient may protect against night blindness?

Vitamin A

What are the fat soluble vitamins?

Vitamin A, D, E, and K

Vitamin A... Vitamin D... Vitamin E... Vitamin K...

Vitamin A: eye health Vitamin D: made from the sun Vitamin E: antioxidant Vitamin K: blood clotting and bone formation

Vitamin ___ poses greatest toxicity risk because it is stored in the ___

Vitamin A; Liver

A deficiency in which nutrient increases the risk for rickets?

Vitamin D

What vitamin is synthesized in the body from cholesterol?

Vitamin D

Protein denaturation refers to:

a change in shape of protein structure due to heat, light, motion, or change in pH.

Studies examining the benefits of vegetarianism cite all of the following, EXCEPT:

a lower incidence of iron-deficiency anemia

The most prevalent vitamin deficiency worldwide is:

a. Vitamin A b. D c. E d. K

Characteristics of the traditional Mediterranean diet include all of the following, EXCEPT:

an avoidance of alcohol