Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MY BIOCHEMICAL NUTRITION > UNIT 7: MACRONUTRIENTS--PROTEIN > Flashcards

UNIT 7: MACRONUTRIENTS--PROTEIN Flashcards

1
Q

Unit 7: Macronutrients - Protein

In nutrition, proteins are classified as either _________ proteins–Contain all amino acids that occur in the body, including essential amino acids, at adequate levels
__________ proteins—Proteins lacking, or low, in some essential amino acids

A

Complete

Incomplete

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Unit 7: Macronutrients - Protein

“__________” Amino Acids: cannot be synthesized by the body.

A

Essential

PVT TIM HLL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Unit 7: Macronutrients - Protein

• Proteins in food are digested (__________) to amino acids and small peptides.
• ___________: Enzymes that hydrolyze proteins – Examples (to jog your memory!)
zymogen
• Pepsin (stomach)
• Trypsin and chymotrypsinogen (pancreas)
• Amino acids are absorbed by the small intestine through specific transporters (some Na+-dependent, some not)
• Small peptides to be absorbed are further digested to amino acids in the intestine wall by _____________

A

hydrolyzed

Proteases

peptidases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Unit 7: Macronutrients - Protein

Transport and Storage

• Amino acids are water soluble
– Transported in body fluids (via ______)

• Storage of amino acids is limited. ~ ___% of serum albumin and skeletal protein may be considered protein reserve

• Body proteins are ___________ for energy under starvation or prolonged exercise
– May also be catabolized for biosynthesis of other more important proteins

A

capillary

5

catabolized

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Unit 7: Macronutrients - Protein

Why aren’t proteins readily catabolized for energy (like fat and carbs?)

Most proteins are _________ proteins and enzymes… We NEED them

A

structural

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Unit 7: Macronutrients - Protein

Major Functions of Proteins
• Enzymes--Are all enzymes proteins?
• Hormones--Are all hormones proteins?
GH, insulin, glucagon, ACTH, etc
• Contractile proteins--Actin, myosin
 • Transporters--\_\_\_\_\_\_\_\_\_\_ (O2 and CO2), Lipoproteins (lipids) Retinol binding protein 
(Vit A)
• Structural proteins--\_\_\_\_\_\_\_\_\_, keratin, elastin, etc
A

Hemoglobin

Collagen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Unit 7: Macronutrients - Protein

Functions of Amino acids

  • Precursor for _________ and _______= Conversion to glucose to maintain blood glucose level or make fat… all a.a. are glucogenic EXCEPT Leu and Lys
  • Energy: Glucose-Alanine cycle = Minor source of energy
A

gluconeogenesis

lipogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Unit 7: Macronutrients - Protein

Functions of Amino acids

Biosynthesis of nucleic acids, DNA, RNA __________, glycine, aspartic acid (and others) are required

• Precursors of specialized products: carnosine, SAM, NTs, melanin…
______________ (Phe»>Tyr), serotonin (Trp), melanin (Tyr)

A

Glutamine

Catecholamines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Unit 7: Macronutrients - Protein

Functions of Amino acids

• Biosynthesis of heme (therefore hemoproteins)
__________, essential for hemoglobin and others

A

Glycine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Functions of Amino acids

Biosynthesis of GAGs (therefore ___________) Glutamate & Glutamine»>Glucosamine

• Biosynthesis of sphingolipids = ________

A

proteoglycans

Serine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Functions of Amino acids

Biosynthesis of peptides and proteins

Biosynthesis of certain amino acids from other
amino acids

Antibody production for immune system

A

Know

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Glucose-Alanine Cycle: Use of amino acids for energy

• Overview:
When muscles produce lactate during times of
decreased oxygen, they also produce _______.
***__________ gets shuttled to liver to make glucose
-Recycles ________ ________ between muscle and liver
-Transports ammonium to the liver»>converted to _______

A

alanine

Alanine

carbon skeletons

urea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Glucose-Alanine Cycle: Use of amino acids for energy

  1. Protein is NOT a major source of ______
  2. Protein is primarily metabolized during __________ (when demands for energy are higher)
  3. Protein used comes from skeletal muscle protein
A

energy

exercise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Summary of the Alanine Cycle

During extended periods of _______, skeletal muscle is degraded as an alternative source of energy.

• _________ is the major amino acid present when muscle (protein) is degraded.

A

fasting

Alanine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Summary of the Alanine Cycle

The glucose-alanine cycle occurs in skeletal muscle to eliminate ________ while replenishing (renewing) the energy supply for muscle.

A

nitrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Summary of the Alanine Cycle

The amino group transported from the muscle to the liver in the form of alanine, is converted to urea in the urea cycle and ________.

A

excreted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Glucose-Alanine Cycle: Use of amino acids for energy

After a high protein meal, the branch-chain amino acids find their way to ____ _____ and incorporate into muscle proteins
Branch-chain amino acids: Val, Leu, Ile

A

skeletal muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Glucose-Alanine Cycle: Use of amino acids for energy

During exercise (or gluconeogenesis), their carbon skeletons are needed to make glucose
...so they are \_\_\_\_\_\_\_\_\_\_\_
A

deaminated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Reactions in SKELETAL muscle

• In muscle cells and other peripheral tissues,
glycolysis produces ________.
• Pyruvate can be __________ to alanine.
• The alanine then enters the blood stream and is transported to the liver.
• Alanine is returned to the liver for _________________.

A

pyruvate

transaminated

gluconeogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Reactions in the LIVER

Within the liver, alanine is converted back to
pyruvate by ___________.

• ___________ is a source of carbon atoms for gluconeogenesis.

A

deamination

Pyruvate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Reactions in the LIVER

_______________ converts pyruvate to form
glucose.

• The newly formed glucose can then enter the
blood for delivery back to the muscle.

• This pathway is termed the __________________ cycle

A

Gluconeogenesis

glucose-alanine

22
Q

Daily Requirement Either of the following criteria can be used:

1. FNB
– By age and average body weight
• Up to 7 months:\_\_\_\_\_\_g /kg body weight
• > 7 months \_\_\_\_\_g / kg (WHO recommends 0.75g/kg) – By % of daily energy need
• Children 1-3: 5-20% kcal
• Children 4-18: 10-30% kcal
 • Adults: 10-35% kcal
2. Dietary Guidelines for Americans
– Adult: 10% of total daily kcal need
A
  1. 0

0. 8

23
Q

Protein Deficiency

 • Causes:
– \_\_\_\_\_\_\_\_\_\_ Causes:
• Economic deprivation
• Improper practice of vegetarianism
– \_\_\_\_\_\_\_\_\_ Causes:
 • GI Disorders
• Allergy to protein-containing foods
A

Primary

Secondary

24
Q

Protein Deficiency–Consequence: Protein-Energy Malnutrition (PEM)

– ____________: “Disease of the first child when the second child comes”
• Due to chronic ________ deficiency
• Signs/Sx: Weakness, edema, loss of hair, skin lesions, diarrhea, fatty liver, recurrent infections (MCC death is ___________).

A

Kwashiorkor

protein

infection

25
Q

Protein Deficiency–Consequence: Protein-Energy Malnutrition (PEM)

________________: Total deficiency of all ergogenic macronutrients (C, P, F)
• No edema. Leads to TOTAL loss of body mass

A

Marasmus

26
Q

Protein Excess

Excess protein leads to loss of _______ and osteoporosis in old age.

In western Europe and US protein intake is ~1.5-2x WHO recommendation

A

Ca2+

27
Q

Protein Excess

Test =__________________ to determine if protein intake is excessive.
Normal:___-____ mg/dL (Upper limit: ___ mg/dL)

A

Blood Urea Nitrogen (BUN)

10-14

21

28
Q

Protein Excess

High protein meals do NOT enhance myofibril synthesis with resistance exercises in the elderly.

Protein foods from animal sources are rich in saturated fats and cholesterol (___________)

A

atherosclerosis

29
Q

Protein Excess

Daily intake of 1.6-2.9 g/kg resulted in:
Increased insulin secretion, but DECREASED sensitivity to insulin (diabetes), renal excretion of acid, oxalate (kidney stones), calcium (hypercalciuria), bone resorption (_________), increased GFR, liver glucose output.

A

osteoporosis

30
Q

Protein Excess

High protein intake (+) correlated with INCREASES in GFR, __________ loss (increased PO4 and SO4), middle and forearm fracture, albuminuria, DM, renal cell and prostate cancer

A

Calcium

31
Q

Protein excess and weight lifting

Excess protein=excess calories
– adds weight as FAT, NOT muscle
(slows down performance)

• Intakes >___% of calories or 2 grams protein/ kg of body weight
– burned for energy
– converted to fat
– Used for primary and structural roles (not muscle mass)

A

15

32
Q

Protein excess and weight lifting

Muscle mass: High protein diets have NEVER been shown to be uniquely beneficial to athletes; muscle size is NOT determined by protein intake
– Muscle size is determined by:
• Training techniques
• __________

A

Genetics

33
Q

Nutritional Quality of a protein food

All ergogenic nutrients supply C, H, & O, but only protein supplies ________ (in the form of amino acids).
– On average, ____% protein is nitrogen

A

nitrogen

16%

34
Q

Nutritional Quality of a protein food

A good “______ _________” is one that is well- digested, absorbed, & retained by the body
Methods for determination:
1. Biologic value (BV), %
2. Net Protein Utilization (NPU), %
3. Protein Efficiency Ratio (PER)
4. Protein Digestion-Corrected Amino Acid Score (PD-CAS)

A

quality protein

35
Q

Nutritional quality of a protein food

1. Biologic value (BV), % = Measures __________ of protein in the body
NOT digestibility or __________

A

retention

absorbability

36
Q

Nutritional quality of a protein food

  1. Net Protein Utilization (NPU), %= Measures retention of protein in the body. Assumes ALL proteins are __________ & absorbed
A

digested

37
Q

Nutritional quality of a protein food

  1. Protein Efficiency Ratio (PER) =
    Average daily wt. gain (g)/ Daily protein consumed (g)

***_______ _________ amount of testing protein (along with adequate amounts of other nutrients) to growing lab animals for a given period of time (e.g. 10 days)

A

Feed controlled

38
Q

Nutritional quality of a protein food

  1. Protein Digestibility-Corrected Amino Acid Score (PDCAAS)

Analyze levels of amino acids in protein, then correct for _________ ________

To determine _____ the protein provides the daily requirements of the essential amino acids as recommended by the RDA.

By this method, _________ protein is a complete protein, even though its BV and NPU are not very high

A

digestibility factor.

how

soybean

39
Q

Animal Protein: ADVANTAGES

• Complete protein source
• Higher BV, PER, & NPU; tied with soy for PDCAAS
• These numbers indicate that animal protein is better than plant –derived protein as it offers more
– nitrogen-retaining,
– anti-________, and
– muscle building activity

A

-catabolic

40
Q

Animal Protein: DISADVANTAGES

A–Excessive protein

  • –Loss of bone calcium = ___________;
  • -Impairs —-kidney function/ kidney stones ——–_____________

B—Fats and Cholesterol

  • -Increase risk for _____ _______, strokes, cognitive impairment, mental diseases (dementia, Alzheimer’s)
  • -Increase risk for some cancers (breast, lung, colon, kidney, brain, prostate)
A

osteoporosis

Dehydration

heart attack

41
Q

Plant Protein: Advantages

May reduce risks of certain cancers
 (No cholesterol or SAFA)
• Lowers blood cholesterol levels
• High in \_\_\_\_\_\_\_\_, vitamins and minerals, complex carbohydrates, and \_\_\_\_\_\_\_\_\_\_\_ (reduce oxidative stress from exercising)
• Soy is a complete protein
A

fiber

antioxidants

42
Q

Plant Protein: Advantages

___________: soy protein is identical to that of egg whites and
casein; higher than proteins in beef and plant sources
• ____________ (antioxidant function)
• ______________ function: prevents CVD and osteoporosis

A

PDCAAS

Isoflavonoids

Phytoestrogen

43
Q

The elite athlete diet (during training/competition):

Between ___-______ g protein/kg body weight
• Most protein from lean meat, eggs, casein, and whey protein (______= most popular supplement)
• 6-7 small meals/day (solid meal= concentrated protein source + fibrous vegetable; liquid meal= shake w/whey protein. Every fourth day, add more complex carbs (yams, oatmeal, brown rice, beans)
• Many abstained from red meat; no alcohol; no additives other than spices (no salt, sugar, dressings, soy sauce, etc.)

A

1–4

whey

44
Q

Practical Issues

• Is amino acid supplementation valid?

Evidence is lacking to support claims of taking basic amino acids to REDUCE body fat.

Use of _____ as supplements in sports may be valid because they are the major ______ amino acids of muscle proteins, and can be used as an ______________ in prolonged exercise in glucose-alanine cycle.

BCAA may increase testosterone, increasing protein

A

BCAA

structural

energy source

45
Q

Practical Issues • Creatine monohydrate

  • Supplement to increase muscle protein synthesis, however, no scientific evidence for it.
  • May increase __________ power (high-intensity, short endurance), muscular strength and endurance, and may spare lean tissue
  • Synthesized from Arg, Gly, S-AM
  • Converted to ______________ for energy storage
  • Side effects: weight gain (water), cramping, dehydration, diarrhea, dizziness
A

anaerobic

creatine phosphate

46
Q

Practical Issues • Aspartame (Nutrasweet)

  • An artifical ________ sweetener (4 kcal/g)
  • Metabolized to Aspartate, _______ & Methanol
  • People with PKU must NOT eat it
  • Side effects: Headache in some people
A

di-peptide

Phenylalanine

47
Q

Practical Issues
• ______________: a risk factor for atherosclerosis.

Homocysteinemia is an independent risk factor for _____________.

Can be lowered by dietary and supplemental _______, vitamins B6 and B12 for the prevention of CVD or stroke

A

Homocysteine

atherosclerosis

folate

48
Q

Focal Points

  • While animal protein is a complete protein that is easily absorbed by the body, it has been linked to numerous chronic diseases: osteoporosis, kidney problems, heart attack, stroke, cognitive impairment, and _______.
  • Plant-protein can aid in the prevention of many diseases, lower cholesterol, fight against cancer, relieve ________ stress during exercise, and boost __________.
A

cancer

oxidative

metabolism

49
Q

Focal Points

_____ is a complete source of protein that offers many advantages in health promotion.

  • While body builders have achieved optimal performance with the use of animal proteins, many vegetarian and vegan body builders have achieved similar success.
  • Plant protein provides all the essential amino acids to meet nutritional needs; the key to a healthy vegetarian diet is _________!
A

Soy

VARIETY

50
Q

Focal Points

  • Protein needs for endurance athletes: 1.2-1.4 g/ kg body weight; for body building athletes: ___-_____ g/kg body weight.
  • The average athlete gets more than enough protein to adequately train (for both endurance and body building competitions).
  • Excess protein adds excess ______ (since the primary fuel of our bodies during activity is glucose and then fat) which adds _____, hindering athletic performance
A

1.6- 1.7

calories

FAT

MY BIOCHEMICAL NUTRITION (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions