Biomolecules concept questions and answers

  1. What are biomolecules?

    Biomolecules are any molecules that are produced by living organisms, including large macromolecules like proteins, nucleic acids, carbohydrates, and lipids, as well as small molecules like primary metabolites, secondary metabolites, and natural products.

  2. What is the primary function of proteins in the body?

    Proteins play a wide variety of roles in the body. They serve as enzymes, structural elements, transport carriers, signaling molecules, antibodies, and more. Their functions are highly diverse due to their ability to fold into many different 3-dimensional structures.

  3. What are the building blocks of proteins?

    The building blocks of proteins are amino acids. There are 20 different amino acids that can be combined to make a protein. The sequence of amino acids determines the structure and function of the protein.

  4. What are nucleic acids and what roles do they play in the cell?

    Nucleic acids are large biomolecules that are crucial for the storage and transmission of genetic information. The two main types of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). DNA stores genetic information, while RNA is involved in protein synthesis.

  5. How does the structure of a lipid molecule contribute to its function?

    The structure of a lipid molecule is generally composed of one glycerol molecule bonded to three fatty acids (in the case of triglycerides). The long hydrocarbon chains of the fatty acids are hydrophobic, allowing lipids to form barriers that separate aqueous environments, as in cell membranes.

  6. What is the role of carbohydrates in organisms?

    Carbohydrates are a major source of energy for most organisms. They can also serve structural roles (as in the case of cellulose in plants) and can be used for cell recognition and signaling.

  7. What are the basic building blocks of nucleic acids?

    The basic building blocks of nucleic acids are nucleotides, which consist of a sugar, a phosphate group, and a nitrogenous base. The sequence of these bases is what determines genetic information.

  8. What is the difference between DNA and RNA?

    DNA and RNA are both nucleic acids, but they differ in several ways. DNA contains the sugar deoxyribose, while RNA contains ribose. DNA is typically double-stranded and forms a double helix, while RNA is typically single-stranded. Additionally, DNA uses the base thymine, while RNA uses uracil.

  9. What is the difference between a monosaccharide, a disaccharide, and a polysaccharide?

    Monosaccharides are the simplest form of carbohydrates and cannot be hydrolyzed to smaller carbohydrates. They include glucose and fructose. Disaccharides consist of two monosaccharide units linked together, such as sucrose (glucose + fructose) and lactose (glucose + galactose). Polysaccharides consist of many monosaccharide units, such as starch, cellulose, and glycogen.

  10. What are the four levels of protein structure?

The four levels of protein structure are primary, secondary, tertiary, and quaternary. The primary structure is the sequence of amino acids. The secondary structure includes local structural elements such as alpha-helices and beta-sheets. The tertiary structure is the overall 3D shape of the protein. The quaternary structure involves the arrangement of multiple protein subunits.

  1. What is an enzyme and how does it work?

An enzyme is a protein that catalyzes chemical reactions in the body. It works by lowering the activation energy of the reaction, thus increasing the rate of the reaction. Enzymes function by binding to specific molecules, called substrates, and converting them into different molecules, called products.

  1. What is ATP and why is it important?

ATP, or adenosine triphosphate, is a nucleotide that serves as the primary energy currency of the cell. It stores energy in its high-energy phosphate bonds, which can be broken to provide energy for various cellular processes.

  1. What is the difference between saturated and unsaturated fatty acids?

Saturated fatty acids have no double bonds between the carbon atoms in their hydrocarbon chain, meaning they are “saturated” with hydrogen atoms. Unsaturated fatty acids have one or more double bonds in their hydrocarbon chain, meaning they have fewer hydrogen atoms.

  1. What is the role of DNA in protein synthesis?

The sequence of nucleotides in DNA determines the sequence of amino acids in proteins. This information is transcribed into mRNA, which is then translated into a protein in the process of protein synthesis.

  1. What is the difference between primary and secondary metabolites?

Primary metabolites are biomolecules that are directly involved in growth, development, and reproduction. They are essential for the survival of the organism. Secondary metabolites, on the other hand, are not directly involved in these processes but often play important roles in interactions with the environment, such as defense against predators or attraction of pollinators.

  1. What is a peptide bond and where is it found?

A peptide bond is a covalent bond formed between two amino acids when the carboxyl group of one amino acid reacts with the amino group of another, releasing a molecule of water. Peptide bonds are found in proteins, where they link together the amino acid residues.

  1. What is the role of RNA in protein synthesis?

RNA plays several roles in protein synthesis. mRNA carries the genetic information from DNA to the ribosome, where protein synthesis takes place. tRNA carries the appropriate amino acid to the ribosome based on the codon in the mRNA. rRNA is a component of the ribosome and facilitates the formation of peptide bonds.

  1. What is a polysaccharide and give an example?

Polysaccharides are large, complex carbohydrates composed of long chains of monosaccharide units. Examples include starch, glycogen, and cellulose.

  1. How are biomolecules involved in the formation of cell membranes?

Biomolecules, specifically lipids and proteins, are essential components of cell membranes. The lipid bilayer forms the basic structure of the membrane, while proteins embedded in the lipid bilayer carry out various functions such as transport, signaling, and cell recognition.

  1. How are enzymes able to catalyze specific reactions?

Enzymes are able to catalyze specific reactions because they have a specific active site that only fits certain substrates. The active site is the region of the enzyme where the substrate binds and the reaction takes place. The shape and chemical properties of the active site match those of the substrate, allowing the enzyme to bind to the substrate and catalyze the reaction.