Protein - Chapter 5 Flashcards
1
Q
Protos
A
- Greek for “first”
- origin of the word protein
2
Q
What distinguishes protein from the other macronutrients?
A
- the presence of the element nitrogen
3
Q
Nitrogen
A
- One of the most abundant elements in the earth’s atmosphere and biosphere, essential to the structure of an amino acid.
4
Q
Fertile soil
A
- supports lush foliage because it is rich in nitrogen
5
Q
Legumes
A
- 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
Q
Fix nitrogen
A
- to remove nitrogen from the atmosphere and render it into a chemical form usable by plants
7
Q
Herbivore
A
- Animal that subsists on foods of plant origin
8
Q
Amino Acid
A
- Basic unit from which protein is made
- Consists of an amine group, a carboxyl group, and various side chains
9
Q
Carnivore
A
- Animal that subsists on foods of animal origin
10
Q
How much of the air does nitrogen compose?
A
78 percent of the air
11
Q
How many amino acids are there to create proteins?
A
20
12
Q
What are amino acids composed of?
A
- Carbon
- Hydrogen
- Oxygen
- Nitrogen
- Sometimes, sulfur
13
Q
Amine
A
- an -NH2 chemical group
- nitrogen is present in this chemical group
14
Q
Carboxyl
A
- a -COOH chemical group
- involved in amino acids
15
Q
essential amino acid
A
- One which cannot be synthesized by the body and must therefore be consumed in the diet
16
Q
Urea
A
- 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
Q
High protein diets:
A
- tax the kidneys
- cause water loss through urination
18
Q
All amino acids consist of:
A
- Amine
- Carboxyl
- A side chain
- the amino acid is named for the side chain, which gives it distinct chemical properties
19
Q
Peptide bond
A
- a chemical bond joining two amino acids
20
Q
Peptide
A
- a short chain of amino acids
- range from dipeptides (2 amino acids) to polypeptides
21
Q
Insulin
A
- A peptide hormone responsible for regulation of blood sugar
- composed of 51 amino acids
22
Q
Hormone
A
- a regulatory compound capable of affecting cells throughout the body
- hormones are also peptides
23
Q
Proteins
A
- A very long chain of amino acids
24
Q
Collagen
A
- 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
