Transcript Proteins

Proteins
• . essential life substance of all living
matter .
• act as structural unit to build our bodies .
• specific structural chemical units amino
acids
• amino [alkaline substance carbon,
hydrogen ,o2& NH2.
10-1
• Essential amino acid are 9 in number :
• Significant in our diet .
• The body unable to syntheses these 9
amino acid so get it from our food
10-2
*types of protein :
• 1-myosin : found in muscle ,has role in
contraction & relaxation of muscle .
• 2-collagen: has role in strength of bone .
• 3-hemoglobin attach with iron in the
RBCs ,help in carrying o2.
• 4- albumin : major plasma protein .
• 5- globulin : alpha beta gamma globulin
,act as antibodies of immuno system
10-3
• complete protein foods comes from
animal source as egg ,milk, cheese ,
meat .
• Incomplete proteins food : plant food
,deficient of one or more essential amino
acid , mostly of plant origin grains
,legumes ,nuts seeds .
• Mixture of protein animals & plant
animals give balance in the ratio of
amino acid .
10-4
• Functions of protein :
• A- growth & tissue building maintenance
.
• B- specific physiological roles :
• Some types of amino acid used as
neurotransmitter substance in the brain .
• Aid in metabolic hormones as thyroxin
• C- available energy
10-5
• **digestion ,absorption & metabolism
of proteins:
• @ mouth : mechanical break down of
food by chewing food mix it with saliva
,push it to stomach .
• @ stomach : break down of protein to
small particles by secreting enzymes
pepsin ,HCL ** provide acidic media to
convert pepsinogen to pepsin
10-6
• Rennin : found in infancy & childhood to
digest milk , rennin prevent too rapid
passage of food from the child stomach .
• @ small intestine :alkaline media in the
intestine ,also pancreatic secretion like
trypsin & chemotropism.
10-7
• ** absorption of amino acid :
• the end product of protein digestion is
the amino acid ,which is water soluble so
absorption occur through blood stream .
• absorption of amino acid at duodenum
carried by pyridoxine [ vit B 6 ].
10-8
• Metabolism of protein :
• Important protein balance is anabolism &
catabolism .
• Protein more found in liver ,pancreas
,kidney & plasma lower protein in the
brain ,muscle ,& skin .
• Tissue catabolism occur in case of
starvation & aging process
10-9
• { tissue break down are exceed than
tissue building } .
• Destruction of protein resulted in ; urea ,
uric acid ,ammonia
10-10
• Protein requirement :
• Protein is essential nutrient .
• Under develop countries protein energy
malnutrition .
• Primary role of amino acid important for
growth ,& maintenance of tissue
10-11
• Age ,body size ,general physical state
has role in protein requirement .
• Disease increase need of protein diet
especially in case of fever .
• Traumatic injury ,post surgical state
require protein for wound healing .
• In case of burn , the need of protein
increased .
• .
10-12
• Protein should be adequate in quantity &
quality.
• The need of protein increase in case of
pregnancy
10-13