Tag: bio-chemistry

Questions Related to bio-chemistry

Source of turpentine oil is

bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

  1. Bark of Cinchona

  2. Lichen

  3. Gymnospermous wood

  4. Algae

Show answer
Correct Option: C
Explanation:

Turpentine oil is an oil which is a volatile oil which is mainly obtained from pines a gymnospermic plant. It is obtained by distillation of resin. Terpenes are the derivative of terpene oil. It is used for thinning oil based paints. It is a very good source of organic synthesis. It is highly viscous in nature. The solid material left behind after distillation is known as rosin.

So, the correct answer is option C.

Prostaglandins are made from

bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

  1. Steroid

  2. Carbohydrate

  3. Amino acid

  4. Fatty acid

Show answer
Correct Option: D
Explanation:
Arachidonic acid is a polyunsaturated omega-6 fatty acid. It is present in the phospholipids and helps in the formation of membranes. It is the most abundant fatty acid in the brain. It is a precursor for the synthesis of prostaglandins. The prostaglandins synthesized is PG$ _2$. They are autocrine and paracrine lipid mediators that act upon platelets, endothelium, uterine and mast cells. 
So, the correct answer is option D.

Prostaglandins synthesized from

bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

  1. Amino acids

  2. Fatty acids

  3. Carbohydrates

  4. Steroids

Show answer
Correct Option: B
Explanation:
Prostaglandins are synthesized by arachidonic acid. Arachidonic acid is a polyunsaturated omega-6 fatty acid. It is present in the phospholipids and helps in the formation of membranes. 
The prostaglandins synthesized is PG$ _2$. They are autocrine and paracrine lipid mediators that act upon platelets, endothelium, uterine and mast cells. It belongs to a class of fatty acid derivative.
So, the correct answer is option B.

What is true of membrane lipids and proteins?

bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

  1. None can flip-flop

  2. Both can flip-flop

  3. Proteins can flip-flop but lipids cannot.

  4. Lipids flip-flop but proteins rarely flip-flop

Show answer
Correct Option: D
Explanation:

Lipid bilayer of the cell membrane contains hydrophilic head groups facing outward and hydrophobic tails facing each other. The transport of phospholipids and lipid-linked oligosaccharides is difficult to achieve due to this bipolar nature. The transmembrane lipid transporter proteins called flippases transport lipids across cell membrane through transverse diffusion by flipping their orientation. Floppases transport in reverse direction. In mammals, this affects various processes such as blood coagulation, immune recognition, and programmed cell death.Most protein molecules do not flipflop due to their extensive polar regions, which are unfavorable in the hydrophobic core of the membrane.

Option D is correct.

The exine of mature pollen grain is composed chiefly ____________.

bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

  1. Lipids

  2. Cellulose

  3. Pectocellulose

  4. Sporopollenin

Show answer
Correct Option: A

Why tails of lipids in the membrane are towards inner part?

bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

  1. The tails is non-polar hydrocarbon and so, protected with an aqueous environment

  2. The tail is polar hydrocarbon and so, is protected from aqueous environment

  3. The non-polar or hydrophobic hydrocarbon trails of lipid, being on inner side ensure their protection from aqueous environment.

  4. The tail is hydrophilic so, it tends to be located in the aqueous inner side of membrane

Show answer
Correct Option: C
Explanation:

The tails of the lipids are made up of fatty acids. These are non-polar hydrophobic so they tend to arrange away from the cytoplasmic face as well as the extracellular face. So, they avoid aqueous medium by arranging themselves towards the inner part of the cell membrane.

Hence, the correct answer is 'The non-polar or hydrophobic hydrocarbons tails of lipid, being on inner side ensure their protection from the aqueous environment.

Which of the following can be traced in phospholipids of brain tissue and soybeans?

bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

  1. Phosphoglycerides

  2. Phosphoinositides

  3. Cholesterol

  4. None of the above

Show answer
Correct Option: B
Explanation:

Phosphoinositides make up a small fraction of cellular phospholipids, They play a fundamental role in controlling membrane-cytosol interfaces, regulation of membrane traffic and the permeability and transport functions of membranes. They are found in brain tissue in animals and soybean seeds. Thus the correct answer is option B.

Deficiency of EFA causes

bio-chemistry lipids functions of lipids biomolecules: chemical constituents of living cells biochemistry

  1. Follicular keratosis

  2. Kidney failure

  3. Sterility

  4. All the above

Show answer
Correct Option: D
Explanation:

Essential fatty acids (EFA) are those fatty acids that body cannot produce on its own and therefore must be supplied from the diet. Deficiency of EFA causes many disease conditions like dry and scaly skin, follicular keratosis (hard and dry skin around hair follicles), bumps on back of upper arms, color variation of skin, dry eyes, mouth and throat, menstrual cramps, dry vagina, excessive thirst, eczema, asthma, hay fever, painful joint. In severe cases, it may result in kidney failure and sterility.

Thus, the correct answer is option D. 

Ammonia formed during digestion is processed in

bio-chemistry coordination in life processes role of intestine digestion in intestine mechanism of digestion

  1. Liver

  2. Small intestine

  3. Large intestine

  4. Stomach

Show answer
Correct Option: A
Explanation:
  • During digestion, the deamination of amino acids results in the production of ammonia (NH3). 
  • However, the liver contains a system of carrier molecules and enzymes which quickly converts the ammonia (and carbon dioxide) into urea
  • This ammonia is an extremely toxic base and its accumulation in the body may cause death.  Hence,  Ammonia is formed during digestion in the liver.
So, the correct answer is 'liver'.

Which of the options given below would not correctly fill the blanks in the following sentence?


In order to absorb and use ____ by the body, these must be broken down by hydrolysis into ___.

bio-chemistry coordination in life processes role of intestine digestion in intestine mechanism of digestion digestive system - organs

  1. Polysaccharides, Monosaccharides

  2. Amino acids, Proteins

  3. Fats, Glycerol and Fatty acids

  4. Disaccharldes, Monosaccharides

Show answer
Correct Option: B
Explanation:
  • Proteins are converted into dipeptides in the stomach which is followed by the conversion of dipeptides to amino acids in the small intestine. These amino acids are absorbed through the wall of the intestine as simple absorbable substances.
  • Hence In order to absorb and use Proteins by the body, these must be broken down by hydrolysis into proteins.
  • So, the correct answer is 'amino acids, proteins'.