Unit 4: Proteins

Question 1

What are amino acids?

Answer 1

The building blocks of proteins. Composed of a single carbon atom with an amine group and an acid group attached.

Question 2

What are protein recommendations based upon?

Answer 2

Nitrogen balance studies, which compare nitrogen lost through excretion with the nitrogen eaten in food.

Question 3

What is nitrogen equilibrium?

Answer 3

Healthy adults should have roughly the same amount of protein in their body at all times.

Question 4

What is positive nitrogen balance?

Answer 4

More protein is being built than being broken down. In growing children and pregnant women.

Question 5

What is negative nitrogen balance?

Answer 5

Muscle or other protein tissue is being broken down and lost. In illness and injury.

Question 6

What are some of the roles of proteins in the body?

Answer 6

Structural components, transporting other substances (lipids, vitamins, minerals, oxygen) around the body, enzymes (protein catalysts), some hormones (usually lipids), antibodies, maintain fluid and electrolyte balance and acid-base balance and as sources of energy and glucose.

Question 7

What is severe acute malnutrition (SAM)?

Answer 7

Characterized by sudden inadequate food intake (caused by drought).
Affects 10% of children, chronic affects 25% of children.

Question 8

What are some of the effects of consuming too much protein?

Answer 8

Heart disease (high fat protein), kidney disease (increases work on kidneys)

Question 9

What is the DRI and ADMR for protein?

Answer 9

0.8g/kg body weight (higher for infants, children, pregnant and lactating women) and 10-35% of total energy

Question 10

What are some examples of essential amino acids?

Answer 10

Histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine

Question 11

What is a conditionally essential amino acid?

Answer 11

A nonessential amino acid that becomes essential because of special circumstances that the need for it is greater than the body’s ability to produce it.

Question 12

How are proteins broken down in the body?

Answer 12

Proteins broken down by pesin and HCl in the stomach to polypeptides which are broken into tri- and dipeptides and amino acids by pancreatic and intestinal proteases. Peptides are broken down by intestinal tri- and dipeptidases to amino acids.

Question 13

How do proteins help fluid distribution?

Answer 13

They cannot pass freely across membranes and they are attracted to water.
A cell wants a certain amount of water inside of it, so it will manufacture enough proteins to hold the water.

Question 14

How do proteins control the acid-base balance of the blood?

Answer 14

Proteins like albumin in the blood act as buffers by gathering up extra hydrogen (acid) ions when there are too many and releasing them when there are too few.

Question 15

What happens when the blood becomes too acidic or basic?

Answer 15

Vital proteins undergo denaturation, losing their shape and ability to function if acidosis or alkalosis occurs.

Question 16

How do proteins play a role in the immune system?

Answer 16

When the body detects antigens, it makes giant protein molecules called antibodies designed specifically to combat them before they even begin.

Question 17

What are some protein based hormones?

Answer 17

Glucagon and insulin

Question 18

What happens when amino acids are broken down for energy use?

Answer 18

The nitrogen-containing amine groups are stripped off and used elsewhere or are incorporated by the liver into urea and sent to kidneys for excretion via urine.

Question 19

What is kwashiorkor?

Answer 19

A clinical expression of SAM, can appear individually or with marasmus.
Failure to grow and develop, edema, changes in the pigmentation of hair and skin, fatty liver, anemia and apathy.

Question 20

What is marasmus?

Answer 20

A clinical expression of SAM, can appear individually or with kwashiorkor.
Poor growth, dramatic weight loss, loss of body fat and muscle and apathy.

Question 21

What is chronic malnutrition?

Answer 21

When a person has enough food to survive, but not to thrive.

Stunted growth

Question 22

How can chronic malnutrition be treated?

Answer 22

Supplemental foods in the community

Question 23

How can SAM be treated?

Answer 23

Requires hospitalization, which means intensive nursing care, diet and medication.

Question 24

What is celiac disease?

Answer 24

An immune disorder in which the absorptive surface of the small intestine is damaged due to an abnormal response to gluten. This results in an inability of the body to absorb nutrients: protein, fat, carbohydrates, vitamins and minerals,
Treated by a gluten free diet for life

Question 25

What is wheat gluten?

Answer 25

A water insoluble protein found in wheat (gliadin), rye, triticale, barley. In flour. Widely used in the production of many processed and packaged foods.

Question 26

What are some symptoms of celiac disease?

Answer 26

Anemia, chronic diarrhea, weight loss, fatigue, cramps and bloating, flatulence and irritability

Question 27

How is celiac disease diagnosed?

Answer 27

Simple blood screening tests.

A small bowel biopsy is the only definitive test, must be done before treatment begins.

Question 28

What is gluten sensitivity?

Answer 28

When a patient gets a variety of symptoms when they eat gluten and feel better on a gluten-free diet but do not have celiac disease.
No damage to the intestine and no TTG antibody is present. No mediation by IgE.
Symptoms include abdominal pain, fatigue, headaches and paresthesia (tingling of the extremities)

Question 29

What is dermatitis herpetiformis?

Answer 29

A chronic skin condition with symmetrical red, raised lesions, with intense itching and burning sensations on the elbows, knees, back of neck, scalp, upper back, butt.
Caused by genetic factors, the immune system and gluten sensitivity.

Question 30

How is dermatitis herpetiformis treated?

Answer 30

Using medications and a gluten free diet

Question 31

What are nutrition complications of celiac disease?

Answer 31

Iron deficiency anemia, lactose intolerance, ostopenia or osteoporosis, folate deficiency, vitamin B12 deficiency, diarrhea, constipation

Question 32

When should a patient start a gluten free diet?

Answer 32

Only after a blood test and upper endoscopy with intestinal biopsy have been completed.
The diet will interfere with the results of the tests.

Question 33

What are some common oral and dental manifestations?

Answer 33

Enamel defects, delayed eruption and recurrent aphthous ulcers.

Question 34

What are complementary proteins?

Answer 34

Two or more proteins whose amino acid assortments complement each other in such a way that the essential amino acids missing from one are supplied by the other