Tag: food and it's constituents
Questions Related to food and it's constituents
The properties of lipids are
-
Insoluble in water and soluble in fat solvents.
-
High energy content.
-
Structural component of cell membrane.
-
All of the above.
Lipids are compounds of carbon, hydrogen and oxygen where ratio of hydrogen and oxygen is less than that of water. Lipids are esters of fatty acids and alcohol which form emulsion with water but are soluble in organic solvents. Some of the common examples of lipids are butter, ghee, cholesterol, carotene etc. Lipids are used as energy source. Lipids provide 9.3 kcal per gram as compared to 4.5 kcal per gram by carbohydrates. Lipids have other important uses also like they lubricate hairs and feathers in animals, reduce transpiration in plants and form components of cell membranes in organisms.
A triglyceride molecule has?
-
Three fatty acids with one glycerol molecule
-
Three fatty acids with two glycerol molecules
-
Two fatty acids with two glycerol molecules
-
One fatty acids with one glycerol molecule
The maximum number of double bonds present in essential fatty acids is
-
1
-
2
-
3
-
4
Unsaturated fatty acids have one or more double bonds like oleic acid (one), linoleic acid (two), linolenic acid (three), and arachidonic acid (four). An unsaturated fatty acid with one double bond is called mono unsaturated fatty acid (MUFA). Fatty acid with more than one double bond is called as polyunsaturated fatty acid (PUFA). Animals cannot synthesize fatty acids with double bonds (Linoleic, Linolenic and Arachidonic acids). Hence, these fatty acids must be obtained in diet and are thus called essential fatty acids.
What are lipids?
-
Composed of fatty acids
-
Triglycerides
-
Insoluble in water
-
All of the above
Lipids are esters of fatty acids and glycerol which form emulsion with water are soluble in organic solvents, example- ghee, butter, carotene, menthol. Fatty acids are long chains of hydrocarbon having an acidic group. Chemically, lipids are diverse and may be acidic or esters but all lipids have a common property that they are hydrophobic and insoluble in water.
Lipids are insoluble in water because lipid molecules are ______________.
-
Hydrophilic
-
Hydrophobic
-
Neutral
-
Zwitter ions
Lipids are hydrophobic means water-hating. They are water-insoluble. Lipids are non-polar molecules while water is a polar molecule, so there is no way for water to attach to a lipid molecule. Instead, the non-polar lipids will bind to themselves, which is why oils and fats form droplets on the surface of the water.
.............. cells/tissue in the body contains average of 18.5% of protein and lipids constituting 3%?
-
Fat
-
Muscle
-
Bone
-
Red blood cell
The average amount of protein present in muscle is 18.5%. Lipids constitute 3% in muscle
Which of the following is the highest energy rich compound?
-
Creatinine phosphate
-
Protein
-
Carbohydrate
-
Fat
Respiration is the oxidation process in which reduced biomolecules like carbohydrates, fats, proteins etc are oxidised to release energy, which can be used for cellular processes. Fats are most reduced biomolecules and their oxidation releases maximum amount of energy. The energy released in oxidation of one gram of fat is twice the energy released in oxidation of one gram of carbohydrate. Hence, carbohydrates are used as an energy reserve biomolecules in living systems.
The structural lipids of cell are
-
Phospholipids
-
Simple lipids
-
Steroids
-
Chromolipids
Phospholipids are a class of lipids that are a major component of all cell membranes as they can form lipid bilayers. Most phospholipids contain a diglyceride, a phosphate group, and a simple organic molecule such as choline; one exception to this rule is sphingomyelin, which is derived from sphingosine instead of glycerol.
Lipids are insoluble in water, because lipids molecules are ___________.
-
Neutral
-
Zwitter ions
-
Hydrophobic
-
Hydrophilic
Lipids are hydrophobic means water hating. They are water insoluble. Lipids are non-polar molecules while water is polar molecule, so there is no way for water to attach to a lipid molecule. Instead, the non-polar lipids will bind to themselves, which is why oils and fats form droplets on the surface of water.
Fats are also known as
-
Lipids
-
Proteins
-
Carbohydrates
-
Nucleic acids