Tag: chemical organization in living beings

Questions Related to chemical organization in living beings

.............. cells/tissue in the body contains average of 18.5% of protein and lipids constituting 3%?

  1. Fat

  2. Muscle

  3. Bone

  4. Red blood cell


Correct Option: B
Explanation:

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?

  1. Creatinine phosphate

  2. Protein

  3. Carbohydrate

  4. Fat


Correct Option: D
Explanation:

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 

  1. Phospholipids

  2. Simple lipids

  3. Steroids

  4. Chromolipids


Correct Option: A
Explanation:

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 ___________.

  1. Neutral

  2. Zwitter ions

  3. Hydrophobic

  4. Hydrophilic


Correct Option: C
Explanation:

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.

Hence C is the correct option. 

Fats are also known as

  1. Lipids

  2. Proteins

  3. Carbohydrates

  4. Nucleic acids


Correct Option: A
Explanation:
Lipids may be broadly defined as hydrophobic or amphipathic small molecules, that originate entirely or in part by carbanion-based condensations of thioesters and/or by carbocation-based condensations of isoprene units. A lipid is considered to be any molecule, that is insoluble in water and soluble in organic solvents. Biological lipids usually refer to a broad grouping of naturally occurring molecules which includes fatty acids, waxes, eicosanoids, monoglycerides, diglycerides, triglycerides, phospholipids, sphingolipids, sterols, terpenes, prenols, fat-soluble vitamins (such as vitamins A, D, E and K) and others. The main biological functions of lipids include their central role in energy storage, as structural components of cell membranes, and as important signaling molecules.

Which biomolecule is made up of only carbon, hydrogen and oxygen?

  1. Lipids

  2. Proteins

  3. Carbohydrates

  4. Nucleic acids


Correct Option: A
Explanation:

Proteins are the polymers of amino acids and have C, H, O, N and S. Carbohydrates and  nucleic acids have C, H, O, N, P and S. Lipids are chemically diverse group and mostly have long hydrocarbon chain composed of C, H and O. Thus, the correct answer is A.

Maximum percentage of lipoprotein is present in

  1. Chylomicron

  2. HDL

  3. VDL

  4. VLDL


Correct Option: A
Explanation:
A lipoprotein is a biochemical assembly that contains both proteins and lipids. There are several types of lipoproteins, each having different functions, but all essentially are transport vehicles. Lipoproteins are categorized and named mainly accordingly to their density which varies with the ratio of lipids to proteins from largest and highest to smallest and heaviest, the four major classes of lipoproteins are chylomicrons, VLDL, LDL and HDLs.
So the correct answer is 'Chylomicron'.

Sphaerosomes have

  1. Cellulose reserve

  2. Protein reserve

  3. Lipid reserve

  4. Both protein and lipid reserve.


Correct Option: C

Which of the following is not a lipid?

  1. Wax/ lecithin

  2. Sterol/ cholesterol

  3. Glycerol/ maltose

  4. Lecithin/ Ghee


Correct Option: C
Explanation:
Lipids:- lipids are molecules that contain hydrocarbons & make up the building blocks of the structures & function of living cells. e.g. - Fats, oil, waxes, contain vitamins (such as A, D, E, & K), Hormones & most of all cell membranes that is not made up of protein.

Select the wrong statement?

  1. The protein part of the holoenzyme is called the apoenzyme

  2. Thylakoids are arranged one above the other like stack of coins forming a granum

  3. Building blocks of lipid are amino acids

  4. Cross-over occurs at pachytene stage of meiosis I


Correct Option: C
Explanation:

Cofactor is a nonprotein part of the enzyme. It can be metal ions or the organic chemical. The cofactors which are organic chemicals are known as coenzyme. These are loosely attached to the apoenzyme. The tightly bound coenzymes are prosthetic group. 

Thylakoids are coin like structure present in the matrix of chloroplast which are stacked to form granum. 
Crossing over in meiosis helps in recombination by exchanging the segments between non homologous chromosomes.
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 is arranged in four fused structure. It is found in plants, animals, and fungi. Steroids such as cholesterol form an integral component of the cell membrane and alter the membrane fluidity.
Lipids are nonpolar molecules so they are unable to interact with the polar molecule like water and thus they are insoluble in water. It is a hydrophobic molecule which is formed by ester linkage of the glycerol molecule with three fatty acid molecule. It does not consist amino acids. But the polymer of amino acids is protein.
So, the correct answer is option C.