Biology · Chemistry

Lipids, Fats, and Biochemistry

1,009 Questions

Lipids, fats, and biochemistry explore the structure and function of biological molecules. This includes fatty acids, cholesterol, trans-fats, and cellular membranes. Questions on this topic frequently appear in science sections of competitive government exams.

Types of fats and lipidsCholesterol and human bodyFatty acidsCellular membranes

Lipids, Fats, and Biochemistry Questions

Multiple choice biology food production food production and microorganisms microbial products - food, medicines and industrial products uses of microorganisms

Caffeine, a constituent of tea and coffee is actually.

  1. A polyamine

  2. An oligosaccharide

  3. An alkaloid

  4. A lipoprotein
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Caffeine is a naturally occurring nitrogenous plant compound classified chemically as an alkaloid, known for its stimulant effects on the central nervous system.

Multiple choice biology animals in daily life introduction to reproduction poultry farming food from animals

The yolk of avian eggs contain

  1. Albumin

  2. Provitellin

  3. Vitellin

  4. Lecithin

  5. All of the above
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Eggs are an important and well-balanced source of essential nutrients. Bird eggs consist of a protective eggshell, albumen (egg white), and vitellus (egg yolk). Yolk of egg consists of 50% of water, 9% lecithin, 16% other proteins which includes albumin, provitellin and vitellin and 23% fats, 0.3% carbohydrates and 1.7% minerals. 

Therefore, the correct answer is option E.

Multiple choice biology the life cycle of animals types of reproduction in animals oviparous and viviparous a study on animals

Yolk is composed of

  1. Carbohydrate

  2. Protein

  3. Phospholipid

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The yolk is a part of an egg, that feeds the developing embryo in animals. It is composed of carbohydrates (3.5%), protein (16%) and fats (phospholipids 26.5%) of total yolk. The main fatty acids present in the yolk is oleic acid, linoleic acid, palmitic acid etc. 

Phosvitins and Lipovitellins are the major proteins present in the yolk. Apart from that yolk is also composed of vitamins - A, D, E, and K. 
So, the correct answer is option D.

Multiple choice biology animal tissues, morphology and anatomy of cockroach types of neuron nervous tissue neural tissues

Myelin sheath has layers of fat and protein

  1. Upto 100

  2. 10-20

  3. Two each

  4. One each
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

  • Myelin is an insulating layer or sheath that forms around nerves, including those in the brain and spinal cord.
  •  It is made up of protein and fatty substances. 
  • This myelin sheath allows electrical impulses to transmit quickly and efficiently along the nerve cells.
  •  If myelin is damaged, these impulses slow down. Hence, the Myelin sheath has layers of fat and protein up to 100.
So, the correct answer is 'up to 100'.

Multiple choice chemistry petrochemicals and polymers food spoilage and food preservation methods of preserving food chemicals in food

Modern oil-based paints contain oils that can dry to form strong, adhesive films by cross-linking of fatty acid chains. Some of these drying oils' are mentioned here. Can you pick the false one?

  1. Linseed oil

  2. Turpentine oil

  3. Soyabean

  4. Castor oil
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Drying oils are prone to hardening upon exposure to air, due to free radical base polymerization, thus forming a flexible, transparent and waterproof film. This property is exhibited by linseed, turpentine and soybean oils. 

Multiple choice chemistry petrochemicals and polymers food spoilage and food preservation methods of preserving food chemicals in food

________ act as protective agent on the surface of animals and plants.

  1. Carbohydrates

  2. Vitamins

  3. Nucleic Acids

  4. Wax
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Wax act as a protective agent on the surface of animals and plants. It protects animals and plants from excessive loss of moisture. It protects the plants and fruits from becoming infected with fungi and bacteria.


Wax contains esters of long chain fatty acids and long chain alcohols or sterol.

Hence, option D is correct.

Multiple choice chemistry petrochemicals and polymers food spoilage and food preservation methods of preserving food chemicals in food

High molecular weight alcohols are present in:

  1. waxes

  2. fats

  3. oils

  4. phospholipids
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

waxes are monoglycerides, these are form by the condensation reaction between monohydroxy alcohol and fatty acid, this is the high molecular weight compound.

Example- Bee wax 
( Hexacosyl palimitate $\rightarrow$ Hexacosyl alcohol+ Palmitic acid)
$C _{26}H _{53}OH + C _{15}H _{31}COOH \overset{-H _2O}\rightarrow C _{26}H _{53}COOC _{15}H _{31}$ 

Multiple choice chemistry petrochemicals and polymers food spoilage and food preservation methods of preserving food chemicals in food

Four oils $A, B, C$ and $D$ have the following values of melting points.
(a) $258$ K (b) $273$ K (c) $295$ K (d) $303$ K
Among these, which oil is prohibited from consumption by cardiac patients?

  1. a

  2. b

  3. c

  4. d
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The oils having higher unsaturation in the fatty acid component have very low melting points. Hence, on the consumption of these oils there is less chance of blockage of blood vessels. The saturated oils have higher melting points and they get solidified easily. Therefore they block the blood vessels and so are prohibited from consumption by cardiac patients. Hence oil D is prohibited from consumption by cardiac patients.

Multiple choice biology food and it's constituents functions and principal sources of lipids chemical organization in living beings lipids

Cholesterol belongs to group

  1. Steroid

  2. Neutral fats

  3. Waxes

  4. Phospholipids
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Steroids are the organic molecule which plays an important role in the growth and development of the body. The molecular structure consists of 17 carbon which are arranged in four fused structure. It is found in plants, animals and fungi. Steroids such as cholesterol forms an integral component of the cell membrane and alter the membrane fluidity. They also acts as hormone receptor for steroidal hormones. It acts as a precursor for the biosynthesis of steroid hormones, bile acid, and vitamin D. 
So, the correct answer is option A.
Multiple choice biology food and it's constituents functions and principal sources of lipids chemical organization in living beings lipids

Lipids are insoluble in water because lipids molecules are

  1. Hydrophilic

  2. Hydrophobic

  3. Neutral

  4. Zwitter ions
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Lipids are hydrophobic (water repelling) and non-polar. Non-polar substances, for instance fats and oils cannot be dissolved in water because they have made up of only carbon-carbon and hydrogen-carbon bonds. Only polar solutes dissolve in polar solvents.

So, the correct option is 'Hydrophobic'.