Biology Final Chapter 3

Nitrogen is an essential element found in proteins and nucleic acids such as DNA and RNA. It is a crucial component of amino acids, which are the building blocks of proteins. Nitrogen is also present in the nitrogenous bases that form the backbone of nucleic acids. On the other hand, sugars and fats primarily consist of carbon, hydrogen, and oxygen, but they do not contain nitrogen. Therefore, nitrogen is the chemical element that is present in proteins and nucleic acids, but not in sugars and fats.

Changing one amino acid within a protein can have significant effects on the protein. The primary structure of a protein refers to the specific sequence of amino acids, so changing one amino acid would alter the primary structure. This, in turn, can affect the overall shape of the protein, as the sequence determines how the protein folds into its three-dimensional structure. The shape of a protein is crucial for its function, so altering the shape can also impact the function of the protein. Therefore, changing one amino acid can have consequences on all of these aspects of a protein.

Nitrogen is an essential chemical element found in proteins and nucleic acids, such as DNA and RNA. It plays a crucial role in the structure and function of these biomolecules, contributing to their overall composition. While sugars and fats do not contain nitrogen, proteins and nucleic acids require it for their formation and biological processes. Therefore, nitrogen is a key element distinguishing proteins and nucleic acids from sugars and fats.

Fat molecules are composed of three fatty acid molecules bonded to one glycerol molecule. The fatty acids provide the long hydrocarbon chains, while the glycerol molecule acts as the backbone for the fat molecule. This bonding process is known as esterification, where the carboxyl group of each fatty acid reacts with the hydroxyl groups of the glycerol molecule to form ester bonds. Therefore, the correct answer is fatty acid and glycerol.

Saturated fats contain the maximum number of hydrogens along the tail. This means that all the carbon atoms in the fatty acid chain are bonded to the maximum number of hydrogen atoms, resulting in a straight and rigid structure. This structure allows saturated fats to pack tightly together, making them solid at room temperature. In contrast, unsaturated fats have one or more double bonds along the tail, which creates kinks in the structure and prevents them from packing tightly, making them liquid at room temperature.

A glucose molecule is the building block of starch, which is a complex carbohydrate formed by multiple glucose molecules bonded together. Similarly, a nucleotide is the building block of a nucleic acid, which is a macromolecule formed by the linkage of nucleotides. Therefore, the relationship between glucose and starch is analogous to the relationship between a nucleotide and a nucleic acid.

Monomers are joined together to form larger polymers through a chemical reaction called dehydration synthesis. In this reaction, a water molecule is removed, allowing the monomers to bond and form a polymer. On the other hand, polymers are broken down into the monomers that make them up through a chemical reaction called hydrolysis. In hydrolysis, a water molecule is added, breaking the bonds between the monomers and separating them into their individual units.

A molecule of fat is formed through a process called esterification, in which three molecules of fatty acids combine with one molecule of glycerol. The fatty acids are long chains of hydrocarbon molecules, while glycerol is a three-carbon alcohol. This reaction results in the formation of a triglyceride molecule, which is the main component of fats.

A glucose molecule is the building block of starch, which is a complex carbohydrate made up of many glucose molecules joined together. Similarly, a nucleotide is the building block of a nucleic acid, which is a macromolecule made up of many nucleotides joined together. Therefore, the analogy is that a glucose molecule is to starch as a nucleotide is to a nucleic acid.

Monomers are joined together to form larger polymers through a chemical reaction called dehydration synthesis. In this reaction, a water molecule is removed as the monomers bond together. On the other hand, polymers are broken down into the monomers that make them up through a chemical reaction called hydrolysis. In hydrolysis, a water molecule is added to break the bonds between the monomers, resulting in the separation of the polymer into individual monomer units.

Changing one amino acid within a protein can have significant effects on the protein. The primary structure of a protein refers to the specific sequence of amino acids, so changing one amino acid would alter the primary structure. This, in turn, can affect the overall shape of the protein, as the arrangement of amino acids determines the protein's folding pattern. The overall shape of a protein is crucial for its proper functioning. Therefore, changing one amino acid can ultimately impact the function of the protein. Thus, the correct answer is "all of the above."

A shortage of phosphorous in the soil would make it especially difficult for a plant to manufacture DNA. Phosphorous is an essential element for DNA synthesis, as it is a key component of the DNA molecule. Without an adequate supply of phosphorous, plants would struggle to produce DNA, which is crucial for genetic information storage and replication. This would ultimately hinder their ability to grow and develop properly.

The term "carbohydrate" includes all the other terms in the list. A carbohydrate is a biological molecule that consists of carbon, hydrogen, and oxygen atoms. Polysaccharides, monosaccharides, and disaccharides are all types of carbohydrates. A polysaccharide is a complex carbohydrate made up of many monosaccharide units, while a disaccharide is composed of two monosaccharide units. Therefore, "carbohydrate" is the broadest term that encompasses all the other terms in the list.

A shortage of phosphorous in the soil would make it especially difficult for a plant to manufacture DNA. Phosphorous is an essential element for the synthesis of DNA molecules, as it is a key component of the DNA backbone. Without sufficient phosphorous, plants would struggle to produce DNA, which is crucial for their growth, development, and reproduction.

Saturated fats contain the maximum number of hydrogens along the tail. This means that each carbon atom in the fatty acid chain is bonded to as many hydrogen atoms as possible, resulting in a straight and rigid structure. This makes saturated fats solid at room temperature. Conversely, unsaturated fats have one or more double bonds along their tail, which results in a bent structure and makes them liquid at room temperature. Therefore, the statement that saturated fats contain the maximum number of hydrogens along the tail is true.