Proteins (Animal N Exam 2)

What are proteins almost made completely of

amino acids

Does protein requirement increase or decrease with age

decrease

What are proteins classified by

shape, solubility and ionic charge

What are the two main characteristics of globular proteins

soluble and mostly digestible

What are the two characteristics of fibrous proteins

insoluble and mostly indigestible

What do conjugated proteins contain

non-protein compounds

Where are albumins found

body fluids, tissues and plant seeds

What are the characteristics of albumins

high aspartic, glutamic acid, leucine and isoleucine and low in glycine

Where are globulins found

all animal and plant cells

Where are prolamines found

many cereals but not oats or rice

What are the characteristics of prolamines

high in proline and glutamic acid and low in essential amino acids

Where are histone found

cell nuclei

What are histones high in

essential amino acids

Where are protamines found

cell nuclei

Where is collagen found

connective tissue

Where are elastins

elastic fibers such as tendon, ligaments and arteries

What are elastins high in

valine, leucine and isoleucine

What are keratins

protective barrier such as skin, fur, hair and wool

What is keratin high in

cystine and cysteine

What are lipoproteins

conjugated lipid and protein

What are glycoproteins

conjugated carbohydrate and protein

What Is cartilage

chondroitin sulfates

What is mucus

amino sugars

What is phenylalanine required for the synthesis of

thyroxin, melanin, norepinephrine and epinephrine

What is tryptophan important for the synthesis of

niacin and serotonin

What is the most limited amino acid for all species

lysine

What is proline used for in birds

feather development and egg shell production

What is glycine used for in birds

required for uric acid and production

Why are nonessential amino acids not required in diet

they are metabolically required

What are the three urea cycle amino acids

ornithine, arginine and citrulline

What are endoenzymes

enzymes digest within a protein molecule

What are exoenzymes

enzymes digest from the ends of a protein molecule

What initiates protein digestion in the stomach

HCI

What cleaves (splits) to form pepsin

HCI

What cleans (splits) to form rennin

pepsin

What are proaminopeptidases specific for

peptides

What are dipeptidases specific for

dipeptides

What is enterokinase specific to

trypsin

What does trypsin activate

small intestinal proenzymes

Is trypsin specific or nonspecific

nonspecific

What is chymotrypsinogen activated by

trypsin

Why aren’t proteins, polypeptides or dipeptides absorbed

too large

Can excess protein be stored

no

What can increase protein requirement

lower quality

What do most transaminations yield

glutamate