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Flashcards in Protein - Chapter 5 Deck (76)
1

Protos

  • Greek for "first"
  • origin of the word protein

2

What distinguishes protein from the other macronutrients?

  • the presence of the element nitrogen

3

Nitrogen

  • One of the most abundant elements in the earth's atmosphere and biosphere, essential to the structure of an amino acid.

4

Fertile soil

  • supports lush foliage because it is rich in nitrogen

5

Legumes

  • member of a plant family capable of fixing nitrogen from the air and thus not dependent on soil fertility to produce a high protein seed

6

Fix nitrogen

  • to remove nitrogen from the atmosphere and render it into a chemical form usable by plants

7

Herbivore

  • Animal that subsists on foods of plant origin

8

Amino Acid

  • Basic unit from which protein is made
  • Consists of an amine group, a carboxyl group, and various side chains

9

Carnivore

  • Animal that subsists on foods of animal origin

10

How much of the air does nitrogen compose?

78 percent of the air

11

How many amino acids are there to create proteins?

20

12

What are amino acids composed of?

  • Carbon
  • Hydrogen
  • Oxygen
  • Nitrogen
  • Sometimes, sulfur

13

Amine

  • an -NH2 chemical group
  • nitrogen is present in this chemical group

14

Carboxyl

  • a -COOH chemical group
  • involved in amino acids

15

essential amino acid

  • One which cannot be synthesized by the body and must therefore be consumed in the diet

16

Urea

  • a nitrogen-containing compoud found in urine and created as a byproduct of the use of protein for energy
  • when nitrogen is left over and must be disposed of

17

High protein diets:

  • tax the kidneys 
  • cause water loss through urination

18

All amino acids consist of:

  • Amine
  • Carboxyl
  • A side chain
    • the amino acid is named for the side chain, which gives it distinct chemical properties

19

Peptide bond

  • a chemical bond joining two amino acids

20

Peptide

  • a short chain of amino acids
  • range from dipeptides (2 amino acids) to polypeptides

21

Insulin

  • A peptide hormone responsible for regulation of blood sugar
  • composed of 51 amino acids

22

Hormone

  • a regulatory compound capable of affecting cells throughout the body
  • hormones are also peptides

23

Proteins

  • A very long chain of amino acids

24

Collagen

  • the primary protein in connective tissue

25

Amylase

  • Digestive enzyme which breaks down starch
  • a protein

26

Sequence

  • Order in which amino acids appear in a protein, affecting its physical and chemical properties

27

DNA

  • the genetic material of a cell
  • inherited traits are carried
  • carries a sequence

28

Genes

  • unit of genetic information
  • the sequence of amino acids in that protein is carried by genes

29

Cooking analogy for proteins

  • each gene = recipe for a protein
  • DNA = cookbook

30

THE process

  1. DNA contains the information necessary to  produce proteins
  2. Transcription or copying of a segment of DNA results in mRNA, a copy of the information in DNA needed to make a protein
  3. the mRNA leaves the nucleus and goes to a ribosome
  4. Amino acids are carried to the ribosome by tRNAs containing the code that matches that on the mRNA
  5. Translation - the information contained in mRNA is used to determine the arrangement, number, and types of amino acids in the protein

31

Denature

  • change the physical and chemical properties of a protein through the action of heat, acid, or other factors
  • began in the stomach
    • strong hydrochloric acid

32

Protease

  • digestive enzyme which breaks protein down
  • break the peptide bonds between amino acids
  • stomach produces protease to start it, the small intestine produces it to finish it

33

What structure does protein provide?

  • muscle and connective tissue (ligaments, tendons, and cartilage) consist of protein
  • strength, elasticiy, and contractive power - protein provides this

34

Protein-sparing

  • the action of carbohydrate in preserving muscle
  • If inadequate carbohydrate is consumed, muscle is broken down to supply blood glucose

35

Blood transport proteins

  • carry nutrients and other substances in the blood
  • sequester them in such a way that they remain inactive until they get where they are needed

36

Hemoglobin

  • a transport protein
  • carries oxygen and carbon dioxide

37

Lipoprotein

  • transport protein for lipids
  • since lipids are not water soluble, they are encapsulated by lipoproteins to travel the water-based bloodstream

38

Homeostasis

  • means "same state"
  • the physiological principle that the bodoy tries to maintain constant conditions
  • ex.
    • state of temperature
    • acidity
    • solute concentration
    • oxygen

39

solute

Substance disolved in a solvent

40

Acid-base balance

  • the degree of acidity or alkalinity in a fluid, caused by an imbalance of hydrogen ions

41

acidity

excess of hydrogen ions

42

basic

deficiency of hydrogen ions

43

ions

  • a charged particular formed when a molecule splits in two
  • electrically charged hydrogen particles

44

Buffer

  • A substance which maintains a constant pH in a solution by absorbing or releasing hydrogen ions as needed

45

Osmosis

  • the movement of water from an area of low solute concentration to an area of high solute concentration through a membrane

46

Osmotic pressure

  • the fore generated by the attraction of the solute on the solvent
  • causes osmosis

47

Kwashiorkor

  • a type of Protein Energy Malnutrition characterized by emanciation and abdominal edema
  • movement of fluid out of the blood stream into the abdominal cavity

48

Enzyme

  • protein that controls and facilitates a chemical reaction
  • catalyze biochemical reactions
  • ex. digestion, making fat, releasing energy from nutrients, synthesizing body constituents

49

Catalyst

  • Substance that participates in and controls a chemical reaction without itself being consumed

50

Substrate

  • the material acted on by an enzyme

51

Precursors

A substance from which another substance is formed

52

Neurotransmitters

  • Substance used to bridge the gap of the nerve synapse and transmit nerve impulses

53

Typtophan and Tyrosine

Two amino acids that are precursors of three neurotransmitters

54

Synapse

  • A gap between nerve cells

55

Antigen

  • Foreign protein which triggers response by immune system (antibody)

56

Antibody

  • immune protein used to attack foreign proteins (antigens)

57

Gluconeogensis

Production of glucose from amino acids (body protein)

Used when carbohydrate stores are depleted

58

RDA of protein

  • 0.8 grams per kg of body weight
  • 58-63 grams for males
  • 46-50 grams for females
  • 12-15 percent of total calories

59

How many essential amino acids exist?

9

60

Essential amino acid (indispensable)

  • One which cannot be synthesized by the body and must therefore be consumed in the diet

61

Conditionally essential amino acid

  • One which cannot be synthesized only under certain conditions, and must be consumed in the diet under these conditions

62

essential

  • not merely necessary, but we cannot manufacture it ourselves

63

Nutrient balance

  • The net flow of a nutrient into an orgnism, resulting in gain or loss of the nutrient

64

Limiting amino acid

  • The amino acid in the shortest supply during protein synthesis, resulting in cessation of synthesis

65

Biological Value

  • A measure of the degree to which an absorbed nitrogen is retained.
  • Nitrogen is here used as a surrogate for protein

Nitrogen retained

-----------------------

Nitrogen absorbed

66

Chemical score

  • A comparison of the amino acid composition of a particular protein with a reference protein (egg)

67

Protein digestibility-corrected amino acid score

  • a form of chemical score of protein quality that also accounts for the digestibility of the protein
  • Gives a realistic measure of a protein's contribution to meeting needs

68

Lacto-vegetarian

  • One who eats only plant foods and dairy products

69

Lacto-ovo-vegetarian

  • One who eats only plant foods, eggs, and dairy products

70

Vegan

  • one who eats only foods of plant origin

71

Complementarity

  • Practice of combining two proteins to improve their amino acids proportions through mutual aupplementation

72

Protein Energy Malnutrition (PEM)

A deficiency of both protein and energy

ex. Marasmus and Kwashiokor

73

Two types of PEM

  1. Marasmus
  2. Kwashiorkor
    • Both characterized by fatigue, exhaustion, and reduced work capacity

74

Edema

  • buildup of fluid in the abdominal cavity
  • bloated bellies as a result of Kwashiorkor

75

Diuresis

  • Urine formation by the kidney as a result of high intakes of protein

76