NCERT Solutions Class 11 Biology Chapter 9

Polymerised biomolecules that contain an array of macromolecules that have a high molecular weight are called Macromolecules. In simpler words, large complex molecules occurring in an intercellular fluid in a colloidal state are called macromolecules. Macromolecules are not visible to the naked eye. They are larger than other molecules with their molecular weight lying between 18-800 daltons (Da). Nucleic acids, proteins, polysaccharides, etc. are some of the broad examples of macromolecules. Some other examples include RNA, DNA, polyester, keratin in hair, nylon, waxes, grease, steroids, hormones, etc.

Micro means “small”. Molecules that are small or in mini size are known as micro molecules. As compared to macromolecules, they have a low molecular weight. These molecules are also known as “monomers”. Monomers combine to form large molecules or “polymers”. Metabolic processes lead to the formation of micro molecules.

The free NCERT Solutions Class 11 Biology Chapter 9 that are available on Extramarks have multiple benefits. All the questions and answers are given in the same place so studying becomes easy for students. The solutions are given chapter-wise and are written in easy language. These solutions contain to-the-point explanations in great detail and are curated by biology experts. 

All proteins are not enzymes but all enzymes are proteins. Enzymes, like proteins, have multiple structures such as primary, secondary, and tertiary structures. An active site in the enzyme helps in binding the substrate molecule. Enzymes function as catalysts but they are not used up during the reaction. Some enzymes need a coenzyme or cofactor to function.

The major enzyme types are as follows:

• Transferases 
• Ligases 
• Hydrolases
• Oxidoreductases
• Lyases
• Isomerases

A nucleotide is the basic unit of nucleic acid. DNA and RNA are made up of the Nucleic acid biomolecules. Genetic codes along with all the information needed to build a body are contained in the nucleic acid. 

Deoxyribonucleic acid or DNA can be found in humans as well as other organisms. This hereditary material can be found in every cell and carries genetic instructions about how to live, develop, and reproduce. Ribonucleic acid or RNA together with DNA makes up the nucleic acid. RNA is involved in several functions of the cell and has three types. 

Different forms of DNA are:

• A-DNA: A-DNA is similar to B-DNA and is a right-handed double helix. 
• B-DNA: B-DNA is a double helical structure that is right-handed. This type of DNA is found in humans.
• Z-DNA: This form is a left-handed double helix.

Different types of RNA are:

• Ribosomal RNA (rRNA)
• Messenger RNA (mRNA)
• Transfer RNA (tRNA)

The functions of RNA are:

• RNA helps in the translation of DNA into proteins. 
• Functions as a messenger that connects the DNA and the ribosomes.
• It helps ribosomes choose the right amino acid. In order to build up new proteins in the body, this choice is essential. 
• It works in the process of protein synthesis as an adapter molecule.
• It carries genetic information in all living cells. 

The functions of DNA and the processes it’s involved in are:

• It stores genetic information.
• During the replication process, it transfers this genetic information to the daughter cells of the cell, from one generation to the next. 
• Transcription
• DNA fingerprinting 
• Cellular metabolism
• Gene therapy.

The DNA molecules are composed of nucleotides – deoxycytidylate (C), deoxyadenylate (A), deoxyguanylate (G), and deoxythymidylate (T). These nucleotides are combined to form long chains known as polynucleotides. DNA includes two chains of polynucleotides. 

Compounds that are insoluble (poorly or completely) in water are known as lipids. However, lipids are soluble in other non-polar solvents like benzene, chloroform, and ether.

Lipids store energy that can be used later. Protecting insects, animals, plants, and vertebrates is one of their other functions. In the structure of the membrane, lipids are a major component. 

Yes, utilising proteins as therapeutic agents is possible. Due to many pharmaceutical needs, proteins have been formulated in laboratories by scientists. These kinds of proteins are called therapeutic proteins. Therapeutic proteins include antigens, renin, diastase, streptokinase, insulin, enzymes, bone morphogenetic proteins, antibody-based drugs, vasopressin, engineered protein scaffolds, and Fc fusion proteins.

Proteins happen to be a useful element in textile industries, biological buffers, research techniques, and cosmetics. However, there has been a significant transformation in the healthcare sector due to therapeutic proteins.

Therapeutic proteins are considered an important part of cancer treatment, HIV, and many more serious ailments such as solubility, tertiary structural stability, cellular interactions, pharmacokinetics, and immunogenicity are affected by therapeutic proteins with carbohydrate profile. 

Molecules that combine to form protein are called Amino acids. Methionine, tryptophan, leucine, valine, lysine, etc. are some examples of the same.

Amino acids have the following main physical properties;

• When amino acids are heated to higher temperatures, they decompose.
• Amino acids usually exist in the d and I form.
• Their melting point is quite high (more than 200 degrees Celsius).
• Amino acids are colourless.
• All amino acids are quite active except glycerine which is quite inactive.