Chp 6

Proteins

Large molecules, made up of chains of amino acids, that are found in all living cells

DNA

The sequence of amino acids is determined by

Amine Acids

The build blocks of protein

20

How many different amino acids are there?

Carbon, Hydrogen, Oxygen & Nitrogen

What are proteins made of?

Peptide

A protein chain made up of fewer than 50 amino acids

Dipeptide

A protein chain made up of 2 amino acids joined together by a peptide bond

Tripeptide

A protein chain made up of 3 amino acids joined together by a peptide bond

Polypeptide

A protein chain consisting of 10 to more than a 100 amino acids joined together by peptide bonds

Carboxyl Group

AKA Acid Group

Carboxyl Group

The organic group attached to an amino acid that is composed of 1 carbon, 1 hydrogen and 2 oxygen atoms

COOH

Abbreviation of an acid group

Side Chain

The part of an amino acid that provides it with its unique qualities; AKA R Group

Peptide Bonds

The bonds that connect amino acids, created when the acid group of 1 amino acid is joined with the nitrogen-containing group of another through condensation

Essential Amino Acids

The body cannot synthesize these, therefore they must be obtained through diet

9

How many essential Amino Acids are there?

Nonessential Amino Acids

The body can synthesize these.

11

How many Nonessential Amino Acids are there?

Conditionally Essential Amino Acids

Those nonessential amino acids, that become essential when the body can no longer make them

Tyrosine & Glycine

These are conditionally essential amino acids

Primary Structure

The 1st stage of protein synthesis

Primary Structure

This is the stage after transcription when the amino acids have been linked together with a peptide bond to form a simple linear chain

Secondary Structure

The geometric shape of a protein caused by the hydrogen ions of amino acids linking together with the amine group, causing the straight chain to fold and twist

Tertiary Structure

The geometric shape of a protein which occurs when the side chains, most often sulfur, form bridges, causing the protein to form even stronger bonds than in the previous structure

Tertiary Structure

This shape has bonds that form loops, bend and folds

Quaternary Structure

This protein shape is formed when 2 or more polypeptide chains cluster together, forming a ball-like structure

Denature

Altering a protein’s shape, generally any but the 1st

Function

Changing a proteins shape changes it’s

Gastrin

A stomach hormone released after eating a meal that stimulates the release of hydrochloric acid

Pepsinogen

The inactive precursor of pepsin; it is stored in the gastric cells and is converted to pepsin by hydrochloric acid

Pepsin

An enzyme in the stomach that begins the digestion of dietary protein

Proteases

Protein-digesting enzymes that can break the peptide bonds linking amino acids together

amino acid pool

a limited supply of amino acids that accumulates in the blood and cells

pools

amino acids are pulled from _____ and used to build new proteins

Protein Turnover

The continual process of degrading and synthesizing protein

Gene

The basic biological unit in a segment of DNA that contributes to the function of a specific protein

Transcription

The 1st stage in protein synthesis

Transcription

The stage in which DNA sequence is copied from the gene and transferred to messenger RNA

mRNA

A type of RNA that carries the genetic info to the ribosomes in the cell

Translation

This is the 2nd phase of protein synthesis

Translation

The phase where info from the mRNA is converted to an amino acid sequence in the ribosomes

tRNA

A type of RNA that transfers a specific amino acid to a growing polypeptide chain in the ribosomes during the process of translation

Elongation

The phase of protein synthesis in which the polypeptide grows longer by adding more amino acids

Sickle-Cell Anemia

A blood disorder caused by a genetic defect in the development of hemoglobin

Deamination

The removal of the amine group from an amino acid when amino acids are used for energy, fat synthesis or gluconeogenesis

Urea

A nitrogen-containing waste product of protein metabolism that is mainly excreted through the urine via the kidneys

Glucogenic Amino Acids

Amino Acids that can be used to form glucose through gluconeogenesis

Gluconeogenesis

The formation of glucose through non carb sources such as glucogenic amino acids, pyruvate, lactate and glycerol

Catalysts

Substances that aid and speed up reactions without being changes, damaged or used up

Catabolic

A metabolic process that breaks large molecules into smaller ones

Hormone

A substance, usually protein or lipid based, that initiates or directs a specific action

Hormones

Insulin, glucagons, ADH, and estrogen are all

Albumin

A protein made in the liver and found in the blood that helps maintain fluid balance

Fluid Balance

The difference between the amount of water taken in and the amount of water taken out

Edema

The accumulation of excess water in the spaces surrounding the cells, which causes swelling

pH

A measurement of the concentration of hydrogen ions in the body fluid

Acidosis

When the blood has excessive H+ ions

Alkalosis

When the blood has a low # H+ ions

Alkalosis

When the pH is higher than normal

Acidosis

When the pH is lower than normal

Buffers

Substances that help maintain the proper pH in a solution by attracting or donating H+ ions

Transport Proteins

Proteins that carry lipids, oxygen, waste, minerals, and vitamins through your blood to your various organs and tissues.

Antibodies

Proteins that bind to and neutralize pathogens as part of the body’s immune response

Immunity

The state of having built up antibodies to a particular foreign substance so that when particles enter the body they are destroyed

Allergen

A substance, such as wheat, that causes an allergic reaction

Nitrogen Balance

The difference between nitrogen intake and excretion

Amino Acid Score

The composition of essential amino acids in a protein compared with a standard, usually egg protein

Limiting Amino Acid

An essential amino acid that is in the shortest supply, relative to the body’s needs, in an incomplete protein

Protein Digestibility Corrected Amino Acid Score

A score measured as a % that takes into account both digestibility and amino acid score and provides good indication of the quality of a protein

Biological Value

The percentage of absorbed amino acids that are efficiently used to synthesize proteins

Complete Protein

A protein that provides all the essential amino acids, along with some nonessential ones

Soy Protein

This is an example of a complete protein

Animal

Proteins from this source tend to be complete

Plant

Proteins from this source tend to be incomplete

Incomplete Protein

A protein that is low in 1 or more of the essential amino acids

Protein Energy Malnutrition

A lack of sufficient dietary protein and/or kilocalories

Kwashiorkor

A state of PEM where there is a severe deficiency of dietary protein; Edema is often seen

Marasmus

A state of PEM where there is a severe deficiency of kilocalories, which perpetuates wasting

Marasmus

AKA Starving

Vegetarian

A person who avoids eating animal foods

Isoflavones

Naturally occurring phytoestrogens, or weak plant estrogens, that function in a similar fashion to the hormone in the human body

Estrogen

The hormone responsible for female sex characteristics