Bimolecules Flashcards
(28 cards)
Differentiate between butter and margrine
Butter has 80% fats while margarine has 80% vegetable oil
Butter is higher in cholesterol while margarine is lower in cholesterol
Butter has 50% saturated fat while margarine has 20% saturated fat
Heteroglycans appear in 3 types of glycoconjugates . They are ________________, _______________ and ____________________
Proteoglycans
Peptidoglycans
Glycoproteins
Mention one example each of disaccharide, triasaccharide, tetrasaccharide and pentasaccharide
Disaccgaride:e.g Maltose, lactose, sucrose
Trisaccharide:e.g Raffinose, maltrise
Tetrasaccharide: e.g stachyose
Pentasaccharide: e.g Fos ( inulin)
Explain the formation of reducing and non reducing sugars. Illustrate with one example each
Reducing sugars are formed by the combination of an anemeric carbon of one sugar with a hydroxyl group of another one thus having s free anomeric carbon which makes it a reducing sugar e.g maltose, lactose etc
WHILE Non reducing sugars are formed by the combination of the anomeric carbon of two sugars thus having no anomeric carbon making them non reducing sugars e.g sucrose, raffinose, etc
What are derived sugars?
Derived sugars are sugar derived by reactions and modifications of their parent monosaccharides.
Types of derived sugars
√Deoxy sugars √Amino sugars √Sugar alcohol √Sugar acids √Sugar phosphates
Cellulose
Human and other mammals can metabolize, starch, glycogen, lactose and sucrose.
Mammals cannot metabolize cellulose because they have they lack enzymes capable of catalyzing the hydrolysis of ß-glycosidic linkages.
Ruminants such as cows and sheep have microorganisms in their rumen that produce ã-glycosidase, which enable them to obtain glucose from grass and plants rich in cellulose
Termites can also obtaine glucose from dietary cellulose because they have cellulose producing bacteria in their digestive tracts
What is a REDUCING END?
A reducing end is the end of the polysaccharide with an anomeric cl not involved in a glycosidic bond
Describe this disaccharide:
Maltose
This is a cleavage product of starch
Disaccharide: Cellulose:
This is a product of the breaking of cellulose
Sucrose
A common table sugar
Lactose
Milk sugar composed of galactose and glucose
Amylose
A glucose polymer
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What are lipids?
Lipids are heterogeneous group of compounds including fats, steroids, waxes etc
Biological importance of lipids
√important dietary constituents because of their high energy value, fat soluble vitamins and essential fatty acids
√fat is stored in adipose tissue which served as thermal insulator in subcutaneous tissues in organs
√non polar lipids act as electrical insulators
√help in the synthesis of hormones
Classify lipids based on saponification, biological functions and structural complexity
Classification based on saponificaton:
Saponifiable lipids: lipids with esters e.g triglycerides
Non saponifiable lipids: lipids without esters e.g prostagladin and cholesterol
Classification of lipids based on biological functions:
Storage lipids: lipids used as stored form of energy in living organisms e.g tricylglycerol
Structural lipids: lipids found in the membranes of organisms e.g phospholipids and glycolipids
Classification of lipids based on structural complexity
Simple lipids: Esters of fatty acids with various alcohols
Complex lipids: Esters of fatty acids with an alcohol and a phosphoric acid residue
Distinguish between essential and non essential fatty acids
ESSENTIAL FATTY ACIDS are poly unsaturated fatty acids that cannot be produced by the body but gotten from dietary sources e.g. linoleic acid
WHILE
NON- ESSENTIAL FATTY ACIDS are produced adequately by the body e.g palmitic acid, steric acid etc
Triglycerol:
The simplest lipids from fatty acids
Saponificaton
Saponificaton is the alkali hydrolysis of fatty acids
Saponificaton value
This is the number of milligram of KOH required to saponify 1g of fat
Iodine number
Iodine number is the measure of the extent of unsaturation of fat equal to the number taken up by 100g of fat
Some physical properties of fatty acids are determined by the______________
Chain length and degree of unsaturation