Biology · Chemistry

Lipids, Fats, and Biochemistry

1,130 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 biomacromolecules biotechnology cell biology and biotechnology biomolecules biology

Which of the following will be different in different animals?

  1. Fats

  2. Carbohydrates

  3. Proteins

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

Proteins are very versatile biomolecules performing different structural and functional roles. Proteins are also information molecules having amino acids joined together in a unique sequence which is decided by the sequence of nucleotides in nucleic acids DNA and RNA. Because different animals will have different sequence of nucleotides in DNA, the proteins synthesized in their body will also have different sequence of amino acids.

Multiple choice biomacromolecules biotechnology cell biology and biotechnology biomolecules biology

Which of the following statement is incorrect? Choose answer: 

  1. The acid insoluble fraction, has only four types of organic compounds, proteins, polysaccharides nucleic acids and lipids

  2. Chemical compounds found in living organisms are of two types, acid soluble and acid insoluble

  3. The compounds which are found in the acid insoluble fraction are called micromolecules

  4. The acid soluble pool represents roughly the cytoplasmic composition
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Biomolecules with molecular weights more than one thousand Dalton are called biomacromolecules. These are found in the acid-insoluble fraction. Lipids are not strictly macromolecules as their molecular weights do not exceed 800 Da but form a part of the acid insoluble pool. The molecules in the insoluble fraction with the exception of lipids are polymeric substances. Lipids are indeed small molecular weight compounds and are present not only as such but also arranged into structures like cell membrane and other membranes. So the acid insoluble fraction has only four types of organic compounds, proteins, polysaccharides nucleic acids and lipids but except for lipids none of them are micromolecules.

So the correct option is 'The compounds which are found in the acid insoluble fraction are called micromolecules'.
Multiple choice biomacromolecules biotechnology cell biology and biotechnology biomolecules biology

Which biomolecule is correctly characteristed? 

  1. Lecithin phosphorylated glyceride found in cell membrane

  2. Palmitic acid unsaturated fatty acid with 18 carbon atoms

  3. Adenylic acid adenosine with glucose phosphate molecule

  4. Alanine amino acid contains an amino acid and an acidic group anywhere in the molecule.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Lecithin is a phosphorylated glyceride. It is a phospholipid with glycerol, fatty acids ,a phosphate group and choline. It is found in the cell membrane. Palmitic acid is a saturated fatty acid with 16 carbon atoms. Adenylic acid is also called as Adenosine monophosphate (AMP). It is an adenosine with a phosphate group and the ribose sugar. It is an ester of phosphoric acid and the adenosine. Alanine is a neutral amino acid. It contains one amino group and one carboxylic group.

Thus, the correct answer is option A.

Multiple choice biomacromolecules biotechnology cell biology and biotechnology biomolecules biology

Chemical composition of a cell's components approx. % dry weight

  1. Carbohydrate, protein, fat, and nucleic acid

  2. Protein, fats, nucleic acid and carbohydrate

  3. Protein, fats, carbohydrates and nucleic acid.

  4. Carbohydrate, fats, proteins and nucleic acid
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The composition of the different organic compounds in the animal body in terms of dry weight is as protein-71%, lipid-12%, nucleic acid-7%,  carbohydrate-5% and inorganic and other materials-5%. These four classes of organic material are important and form the basis of organic constituents in the cell. All these macromolecules except lipids are formed by the process of polymerisation. Due to their large size and complex 3-dimensional shape, these organic biomolecules function as structural components, enzymes, energy sources,molecular messengers, nutrient stores and sources of genetic information. Carbohydrates are polyhyroxyaldehydes or polyhyroxyketones or substances that gives this on hydrolysis. They are classified as monosaccharides, oligosaccharides and polysaccharides. Pentoses and hexoses are the most important sugars. Complex polysaccharides are important components of inter-cellular ground substances. Lipids are major and essential components of biological membranes. They are important dietery components and forms major forms of energy, because of their high calorific value. Protein is a polymer of different amino acids linked together by peptide bonds. Proteins can be fibrous or globular. Structural proteins serve as building materials for cells and tissues. Functional proteins regulate metabolism. Nucleotides, the monomer units of nucleic acids serve many important functions in cells. They store the genetic information in them. They are also primary carriers of chemical energy in cells, structural components of many enzyme cofactors and cellular second messengers. Thus, the four macromolecules play a significant role in performing various cellular functions.

Multiple choice biology respiration and energy transfer respiratory quotient-basic respiration-plants respiratory quotient

R.Q. is more than one in the case of 

  1. Fat

  2. Fructose

  3. Glucose

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

R.Q. is the ratio of the volume of carbon dioxide evolved and oxygen consumed in respiration.

Inorganic acids, the evolution of carbon dioxide is more than the oxygen require that is the reason organic acids has R.Q. more than 1.
So the correct option is 'Organic acid'.

Multiple choice biology respiration and energy transfer respiratory quotient-basic respiration-plants respiratory quotient

RQ of which diet is less than unit?

  1. Carbohydrate

  2. Fats

  3. Organic acid

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

Respiratory quotient (RQ) is defined as volume of carbon dioxide released to volume of oxygen absorbed during the process of aerobic respiration of a substrate. 

The value of RQ for carbohydrates is unity. 
Fats are comparatively more reduced. They have much more carbon and less of oxygen. Hence, oxidation of fats requires a lot of oxygen to release same amount of carbon dioxide. As a consequence the value of RQ for oxidation of fats is less than unity.

Multiple choice biology respiration and energy transfer respiratory quotient-basic respiration-plants respiratory quotient

Which one yields the highest energy per gram

  1. Carbohydrate

  2. Protein

  3. Fat

  4. Amino acids
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Our food contains three main constituents: carbohydrates, fats and proteins. The amount of energy released when one gram of any of these food elements is burned is known as calorific value. Thus calorific value of food indicates as to how much is the energy value of food which the human body can gain through metabolism. It is usually given in kcal/gm. Fats form the most concentrated source of energy in our diet. 1 gram of fat yields 9.5 kcal of energy which is the highest among the food components. 1 gram of carbohydrates and proteins yield almost similar amount of energy which is equal to 4 kcal. 

Thus, the correct answer is option C. 

Multiple choice chemistry water in our life where do we get water from? why conserve water uses of water

Study the given statements and select the correct answer.


(I) Lipids are macromolecules but obtained under-macromolecular fraction due to their insoluble nature in the aqueous medium of a cell.
(II) Water is the most abundant chemical in a living organism.
(III) The first respiratory substrate is lipid.
(IV) Dihydroxyacetone occurs in d and l form.

  1. I, II and IV are correct

  2. I, II & III are correct

  3. I, II are correct

  4. III and IV are correct
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
(I) Lipids are micromolecules as they are not polymers. These are monomers made up of three fatty acids attached to a glycerol. Because these are hydrophobic, they are obtained under the macromolecule fraction.
(II) Water is the most abundant chemical in the living organism.
(III) Glucose acts as the first respiratory substrate.
(IV) Dihydroxyacetone occurs in both the D and L form.
Hence, the correct answer is 'I, II and IV are correct'
Multiple choice zoology respiratory system phases in respiration human respiratory system parts of respiration

Pulmonary surfactant is 

  1. Amino acid

  2. Steroid

  3. Phospholipid

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • Pulmonary surfactant is a surface-active lipoprotein complex (phospholipoprotein) formed by type II alveolar cells.
  •  The proteins and lipids that make up the surfactant have both hydrophilic and hydrophobic regions. 
  • It helps to increase pulmonary compliance, To prevent a collapse of the lung at the end of expiration. Hence, Pulmonary surfactant is a phospholipid.
So, the correct answer is ' phospholipid'.
Multiple choice biology what do animals eat? digestion in ruminants nutrition in other organisms busy at work - our internal organs

Grass is rich in the substance called as

  1. Amino acid

  2. Fatty acid

  3. Cellulose

  4. Pepsin
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The grass is a bulb plant. The cell wall of grass leaves is made of cellulose. Cellulose is stored food substance in plants and it is typically the most abundant constituent by mass in the grass.
So, the correct answer is 'Cellulose'.
Multiple choice evs food components and nutrition need for nutrients nutrition and its deficiency nutrition and its need

The most important component formed by plants which is useful for the growth is

  1. Carbohydrates

  2. Proteins

  3. Fats

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Proteins are major element required in the growth of the plant cells. In plants, all the 20 amino acids should be formed in the plant body because they cannot take them up fro any other source. Proteins are essential as they are the basic constituents of enzymes, cell membrane, and transport systems.

So, the correct option is 'Proteins'

Multiple choice zoology human body body defense system drug-target interaction pharmaceutical products and drug action

The skin has an outer layer made up of .......... which is almost impermeable to germs.

  1. Keratin

  2. Lipid

  3. Fat

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

The skin is the largest organ of the body, with a surface area of 18 square feet. Its two main layers are the epidermis (outer layer) and dermis (inner layer). The epidermis has several strata (layers) that contain four cell types. Keratinocytes produce keratin, a protein that gives skin its strength and flexibility and waterproofs the skin surface.

So, the correct answer is option A.