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Explain the process of hydrolysis in proteins: cleavage of peptide bonds to obtain free amino acids and low molecular weight peptides, consuming a molecule of water for each broken bond. Identify saturated and unsaturated fatty acids: Saturated fatty acids have hydrocarbon chains connected by single...

Explain the process of hydrolysis in proteins: cleavage of peptide bonds to obtain free amino acids and low molecular weight peptides, consuming a molecule of water for each broken bond. Identify saturated and unsaturated fatty acids: Saturated fatty acids have hydrocarbon chains connected by single bonds only. Unsaturated fatty acids have one or more double bonds. Explain the polarity of water: a water molecule has two poles, oxygen is slightly negative and hydrogen is slightly positive concept of pH, provide examples, and compare pH values to determine the acidity / alkalinity of solutions: measure of relative amount of hydrogen and hyrdoxyl ions in the water, pH under 7 is acidity and pH greater than 7 means a base. Alkalnity is waters ability to neutralize acids or reset acidity acting as a buffer. Distinguish between the concept of monomer and polymer: monomer is one molecule and a polymer is several monomers. Provide specific examples of monomers and polymers of carbohydrates: monomers are monosaccharides such as glucose, fructose and galactose and polymers are dissaccharides and polysaccharides such as sucrose, maltose and lactose, for polysaccharides there is glycogen, starch, cellulose Distinguish between hydrogen bonds and covalent bonds: hydrogen bond: A weak bond in which a hydrogen atom in one molecule is attracted to an electronegative atom (usually nitrogen or oxygen) in the same or different molecule. covalent bond: A type of chemical bond where two atoms are connected to each other by the sharing of two or more electrons Explain the process of polymerization of carbohydrates through dehydration synthesis and the formation of glycosidic bonds. In dehydration synthesis, two monosaccharides join by removing a water molecule (H₂O), forming a *glycosidic bond*. For example, when two glucose molecules bond, one loses a hydrogen (H) and the other loses a hydroxyl group (OH), releasing water and forming a disaccharide like maltose. This process can continue, creating long carbohydrate polymers like starch or cellulose. Explain the process of hydrolysis in carbohydrates It splits the glycosidic bonds between monosaccharides, turning complex carbohydrates (like polysaccharides or disaccharides) into simpler sugars. For example, adding water to sucrose breaks it down into glucose and fructose. Explain the functions of carbohydrates by providing specific examples. 1. *Energy Source: Glucose* is used in cellular respiration to produce ATP. 2. *Energy Storage: Glycogen in animals and starch* in plants store glucose for later use. 3. *Structural Support: Cellulose provides strength to plant cell walls, and chitin* does the same for fungal cell walls and insect exoskeletons. 4. *Cell Signaling: Glycoproteins* on cell surfaces help with cell recognition and communication. Explain the importance of the valence of carbon atoms in relation with bonding to other atoms. Carbon's valence of 4 allows it to form *four covalent bonds with other atoms, making it extremely versatile. This enables the creation of long chains, rings, and complex structures* like proteins, carbohydrates, and nucleic acids, which are essential for life. Identify the parts of an amino acid / protein. e the amino group, the carboxyl group, and the side-chain or R group all attached to the α-carbon. Explain the process of polymerization of amino acids through dehydration synthesis and the formation of peptide bonds Amino acids polymerize through *dehydration synthesis, forming peptide bonds. In this process, the amino group (NH₂) of one amino acid bonds with the carboxyl group (COOH) of another, releasing a water molecule (H₂O). This results in a peptide bond linking the two amino acids. Repeatedly joining amino acids in this way forms polypeptides*, which fold into proteins. Describe the function of enzymes and their biological importance. catalysts that increase the rate of virtually all the chemical reactions within cells, help facilitate biochemical reactions in our bodies. They aid in everything from breathing to digestion Explain the functions of proteins by providing specific examples. Antibodies are specialized proteins that defend the body against antigens or foreign invaders. Contractile proteins are responsible for muscle contraction and movement。 All enzymes identified thus far are proteins. speed up reactions. Hormonal proteins are messenger proteins that help coordinate certain bodily functions.eg: Structural Proteins: A large group of structural proteins maintains and protects the structure of the animal body. Storage proteins reserve amino acids for the body until ready for use. Examples of storage proteins include. Transport proteins are carrier proteins that move molecules from one Explain the importance of protein folding and its relationship with a protein biological function. crucial for proteins to acquire their 3D conformation and exert their biological functions. permits the protein to become biologically functional. Compare and contrast the four levels of protein folding, and visually identify these four levels in a protein diagram. primary, secondary, tertiary, and quaternary structure. Explain what DNA and RNA stand for. Nucleic acids, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) Outline the central dogma of molecular biology. The central dogma of molecular biology is a theory stating that genetic information flows only in one direction, from DNA, to RNA, to protein, or RNA directly to protein. Explain / identify the different parts of a nucleotide. A nucleotide is the basic building block of nucleic acids (RNA and DNA). A nucleotide consists of a sugar molecule (either ribose in RNA or deoxyribose in DNA) attached to a phosphate group and a nitrogen-containing base Compare and contrast the structure, composition, and functions of DNA and RNA. DNA is a double-stranded molecule that has a long chain of nucleotides. RNA is a single-stranded molecule which has a shorter chain of nucleotides. DNA replicates on its own, it is self-replicating. RNA does not replicate on its own. List the nitrogenous bases for both DNA and RNA. The nitrogenous bases of DNA are adenine (A), guanine (G), Cytosine (C) and thymine (T). The nitrogenous bases of RNA are adenine (A), guanine (G), Cytosine (C) and uracil (U). Explain the process of polymerization of nucleotides through dehydration synthesis and the formation of phosphodiester bonds. As water molecules are removed during their polymerization, the process is known as dehydration synthesis.The polymerization of nucleotides occurs in a condensation reaction in which phosphodiester bonds and H2O molecules are formed。 reacting two hydroxyl groups in phosphoric acid with the hydroxyl group on other molecules to produce an ester link Explain the process of hydrolysis in nucleic acids. Some nucleases can hydrolyse linkages between 2 adjacent nucleotides at internal positions in the DNA or RNA strand and proceed stepwise from that end. Describe the composition of triglycerides. A triglyceride is composed of glycerol and three fatty acids. Explain the process of dehydration synthesis to create triglycerides and the formation of ester bonds. composed of one glycerol and three fatty acids. The three hydroxyl groups of the glycerol molecule and the carboxyl groups of three fatty acids interact to form ester bonds with the removal of three water molecules. Ester bonds form between the glycerol and the fatty acid chains. Explain the process of hydrolysis in triglycerides. In the presence of acid and heat, or under biological conditions, triglycerides (fats) can be hydrolysed to produce glycerol and three fatty acids. Compare and contrast saturated and unsaturated fatty acids. Saturated fatty acids lack double bonds between the individual carbon atoms, while in unsaturated fatty acids there is at least one double bond in the fatty acid chain. List the different types of lipids and explain their functions. Triglycerides transport and store energy. Steroid hormones send messages in cells. Bile salts from cholesterol help digest fat. Fatty acids metabolize to create energy. Phospholipids and cholesterol make biological membranes. Explain the composition of phospholipids and their role in the cell membrane. its a lipid made of a glycerol and two fatty acid tails and a phosphate linked head group, it acts a barrier to protect the cell against various environmental insults., allows cellular process to occur in subcellular compartments Explain the concept of hydrogen bonding. Two atoms in other existing chemical bonds are attracted to eachother. Cohesion water molecules sticking to eachother adhesion water molecules sticking to other objects, surfaces or substances. capillary action movement of water using either adhesion or cohesion surface tension The property of the surface of a liquid that allows it to resist an external force, due to the cohesive nature of its molecules universal solvent its ability to dissolve so many different materials density 1 gram. The relationship between the mass of substance how much volume it takes up. high heat capacity it absorbs the heat before it gets hot, it can withstand high temperatures. high heat of vaporization The amount of heat necessary to cause a transition between a liquid and a gas; Large amount of heat is needed to vaporize liquid. More hydrogen bonds must be broken concept of buffer and the importance for living organisms. it allows them to maintain homeostasis, or a relatively consistent internal environment. Identify macromolecules based on their composition: C, H, O, N, S, P. Carbohydrates: C, H, O. Lipids: C, H, O. Some complex lipids may also contain phosphorus Proteins: C, H, O, N, sometimes S. Nucleic Acids (DNA and RNA): C, H, O, N, P. Phosphorus is a key part of the phosphate backbone of DNA and RNA.