Bio 1 - Chapter 2 Vocab Quiz

Enzymes are specialized proteins that act as catalysts for chemical reactions in living organisms. They speed up the rate of these reactions by lowering the activation energy required for the reaction to occur. Enzymes are highly specific in their action, as each enzyme typically catalyzes only one specific reaction or a group of closely related reactions. They bind to specific molecules called substrates and convert them into products. Enzymes are essential for various metabolic processes in the body and play a crucial role in maintaining homeostasis.

An atom is the smallest unit of matter that cannot be broken down by chemical means. It is the basic building block of all elements and compounds. Atoms consist of a nucleus, which contains protons and neutrons, and electrons that orbit around the nucleus. Chemical reactions can rearrange atoms to form new compounds, but they cannot break down atoms into smaller particles. Therefore, an atom is the correct answer as it is the fundamental particle that retains the properties of an element.

An exothermic chemical reaction releases more energy than it absorbs. This means that during the reaction, energy is being released into the surroundings, usually in the form of heat. In an exothermic reaction, the products have lower energy than the reactants, resulting in a net release of energy. This can be observed in many common reactions, such as the combustion of fuels or the reaction between an acid and a base.

An endothermic chemical reaction absorbs more energy than it releases. This means that the reaction requires an input of energy in order to proceed. The reactants have a lower energy level than the products, so energy is absorbed from the surroundings to make up the difference. As a result, the surroundings become cooler.

A compound is a substance made up of the joined atoms of two or more different elements. It is formed when atoms of different elements chemically combine to form a new substance with different properties than the individual elements. Compounds have a fixed ratio of atoms and can be represented by a chemical formula. Examples of compounds include water (H2O), carbon dioxide (CO2), and sodium chloride (NaCl).

Activation energy is the amount of energy required to initiate a chemical reaction. It is the energy barrier that must be overcome for the reactants to transform into products. Activation energy is necessary because it allows the reactant molecules to acquire enough energy to break the existing bonds and form new ones. Without activation energy, reactions would not occur spontaneously. Bond energy refers to the energy required to break a specific bond, exothermic energy is the energy released during a reaction, and stored energy refers to potential energy stored in chemical bonds.

Bond energy refers to the amount of energy that is required to break a chemical bond. It is the energy needed to overcome the attractive forces between atoms in a molecule and separate them from each other. This energy is typically measured in kilojoules per mole (kJ/mol) and can vary depending on the specific bond being broken. Bond energy plays a crucial role in chemical reactions, as breaking bonds requires energy input, while forming bonds releases energy. Therefore, bond energy is an essential concept in understanding the stability and reactivity of chemical compounds.

In a chemical reaction, the substance that undergoes a change is called a reactant. Reactants are the starting materials that are transformed into different substances, known as products, during the reaction. Catalysts are substances that facilitate the reaction but are not consumed or changed themselves. Amino acids are organic compounds and do not specifically refer to substances involved in chemical reactions.

pH is the measure of hydrogen ions (H+) in a solution. It indicates the acidity or alkalinity of a solution on a scale of 0 to 14. A pH value below 7 indicates acidity, while a pH value above 7 indicates alkalinity. The lower the pH value, the higher the concentration of hydrogen ions, making the solution more acidic. Conversely, a higher pH value indicates a lower concentration of hydrogen ions and a more alkaline solution. Therefore, pH is the correct answer as it directly measures the concentration of hydrogen ions in a solution.

Enzymes are biological catalysts that speed up chemical reactions in living organisms. They have a specific shape that allows them to bind to specific molecules called substrates. The substrates are the specific reactants that the enzyme acts on, and they fit into the enzyme's active site. Once the substrates are bound to the enzyme, the enzyme can catalyze the reaction and convert the substrates into products. Therefore, the correct answer is substrates.

In a chemical reaction, the substance that is being produced is called a product. This is because a chemical reaction involves the transformation of reactants into new substances, which are the products of the reaction. The reactants are the substances that participate in the reaction and undergo a change, while the product is the resulting substance that is formed as a result of the reaction. Therefore, the correct answer is product.

Equilibrium is reached when both reactants and products are made at the same rate. This means that the forward and reverse reactions are occurring at equal rates, resulting in a dynamic balance between the reactants and products. At equilibrium, the concentrations of reactants and products remain constant over time, although the individual molecules are continuously interconverting. This state is important in chemical reactions as it represents a point of stability and allows for the efficient utilization of reactants to produce products.

A solute is a substance that dissolves in a solvent. When a solute is added to a solvent, it disperses evenly throughout the solvent, forming a solution. This process is known as dissolution. The solute particles become surrounded by solvent particles, breaking the intermolecular forces between solute particles and allowing them to mix uniformly. The solute can be a solid, liquid, or gas, and it can dissolve in various solvents, such as water, alcohol, or oil. The solute-solvent interaction is crucial in many chemical and biological processes, including drug delivery, osmosis, and digestion.

Carbohydrates are molecules composed of carbon, hydrogen, and oxygen, and they include sugars and starches. They are a major source of energy for the body and play a crucial role in various biological processes. Carbohydrates can be found in foods such as fruits, vegetables, grains, and dairy products. They are broken down into glucose during digestion, which is then used by the body for energy production. Carbohydrates also have structural functions, such as providing support to plant cell walls.

A covalent bond forms when atoms share a pair of electrons. In this type of bond, the shared electrons are attracted to the nuclei of both atoms, creating a strong bond between them. This sharing of electrons allows atoms to achieve a stable electron configuration, similar to that of noble gases. Covalent bonds are commonly found in molecules and compounds, such as water (H2O) and carbon dioxide (CO2).

An element is a pure substance made of only one kind of atom. This means that all the atoms in an element have the same number of protons in their nucleus. Examples of elements include hydrogen, oxygen, and gold. Compounds, on the other hand, are made of two or more different elements chemically combined. Atoms are the basic building blocks of matter, but they can combine to form molecules or compounds. Ions are atoms or molecules that have gained or lost electrons, resulting in a positive or negative charge.

An ionic bond forms through the electrical force between oppositely charged ions. In an ionic bond, one atom donates electrons to another atom, resulting in the formation of positively and negatively charged ions. These ions are then attracted to each other by the electrical force, creating a strong bond between the atoms. This type of bond is commonly found in compounds composed of metals and nonmetals.

A polymer is a macromolecule made of many smaller molecules bonded together. This is because polymers are formed through a process called polymerization, where monomers (smaller molecules) join together to form a larger molecule with repeating structural units. This results in the formation of a macromolecule with unique properties and functions.

Chains of carbon and hydrogen atoms that form a monomer of lipids are called fatty acids. Lipids are a type of organic molecule that includes fats, oils, and waxes. Fatty acids are the building blocks of lipids, and they consist of a long chain of carbon and hydrogen atoms with a carboxyl group at one end. These chains can vary in length and can be saturated (containing only single bonds) or unsaturated (containing one or more double bonds).

A hydrogen bond is formed when the positive region of one water molecule, which is the hydrogen atom, is attracted to the negative region of another water molecule, which is the oxygen atom. This attraction occurs due to the difference in electronegativity between the hydrogen and oxygen atoms. Therefore, the correct answer is hydrogen bond.

A catalyst is a substance that lowers the activation energy required to initiate a chemical reaction, resulting in an increased reaction rate. By providing an alternative reaction pathway with lower energy barriers, catalysts enhance the efficiency of reactions without being consumed or permanently altered in the process. This allows for faster and more efficient production of desired products.

A molecule is the smallest unit of a substance that keeps all of the physical and chemical properties of that substance. It can consist of one element or two or more elements bonded together. A compound is a substance composed of two or more different elements chemically bonded together. An ion is an electrically charged atom or molecule. A solution is a homogeneous mixture of two or more substances.

Lipids are non-polar macromolecules that include fats, oils, and cholesterol. Unlike carbohydrates, proteins, and nucleic acids, lipids are hydrophobic and do not dissolve in water. They play important roles in energy storage, insulation, and protection of organs. Lipids are made up of long hydrocarbon chains, which give them their non-polar nature. Fats and oils are examples of lipids that provide a concentrated source of energy, while cholesterol is a lipid that is important for cell membrane structure and hormone synthesis.

Proteins are polymers made of amino acids. Amino acids are the building blocks of proteins and are joined together through peptide bonds to form long chains. These chains can fold and twist into complex three-dimensional structures, giving proteins their unique functions and properties. Proteins are essential for various biological processes such as enzyme catalysis, cell signaling, and structural support in the body.

A chemical reaction is the process in which substances are transformed into different substances by breaking and reforming chemical bonds. During a chemical reaction, the atoms of the reactants rearrange to form new products. This rearrangement involves the breaking of existing bonds and the formation of new bonds. Therefore, a chemical reaction is the correct answer as it accurately describes the process of changing substances into different substances by breaking and reforming chemical bonds.

Adhesion refers to the attraction between different substances. It is the force that causes molecules of different substances to stick together. This can occur between molecules of the same type or different types. Adhesion is responsible for phenomena such as capillary action, where liquids are able to move against gravity in narrow tubes. It is also important in processes like wetting, where a liquid spreads out over a solid surface.

A monomer is a molecular subunit of a polymer. Polymers are large molecules made up of repeating subunits called monomers. These monomers can join together through chemical reactions to form long chains or networks, resulting in the formation of a polymer. Therefore, a monomer is a fundamental building block for the synthesis of a polymer.

Amino acids are molecules that contain carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur, and are used to build proteins. They are the building blocks of proteins and are essential for various biological processes in the body. Amino acids are linked together in a specific sequence to form proteins, which play a crucial role in the structure and function of cells and tissues. Therefore, amino acids are the correct answer to the question.

A substance that removes protons (H+ ions) from a solution is called a base. Bases are characterized by their ability to accept protons, also known as hydrogen ions, and they tend to increase the concentration of hydroxide ions (OH-) in a solution. This property allows them to neutralize acids and regulate the pH levels in a solution. Examples of bases include substances like sodium hydroxide (NaOH) and ammonia (NH3).

Cohesion refers to the attraction between substances of the same kind. This means that molecules of the same substance are attracted to each other, causing them to stick together. This phenomenon is commonly observed in liquids, where cohesive forces allow the liquid to maintain its shape and form droplets. Cohesion is important in various natural processes, such as the movement of water in plants through capillary action and the formation of surface tension.

An ion is an atom, radical, or molecule that has gained or lost one or more electrons, resulting in a negative or positive charge. Ions are formed through the process of ionization, which occurs when electrons are transferred between atoms. This transfer of electrons can create a charged particle, either positively or negatively charged, known as an ion. Ions play a crucial role in many chemical reactions and are essential for the functioning of biological systems.

A mixture that is consistent throughout is called a solution. In a solution, the solute is evenly distributed and dissolved in the solvent, resulting in a homogeneous mixture. This means that the properties and composition of the solution are the same throughout, making it consistent. Therefore, the correct answer is solution.

A solvent is a substance in which a solute dissolves and is in greatest concentration in a solution. Solvents have the ability to dissolve other substances, such as solutes, and create a homogeneous mixture known as a solution. In a solution, the solvent is present in a larger amount compared to the solute. The solute, on the other hand, is the substance that is dissolved by the solvent. Therefore, the solvent is in the greatest concentration in a solution.

A substance that releases protons (H+ ions) in solution is called an acid. Acids are characterized by their ability to donate protons, which results in an increase in the concentration of H+ ions in solution. This increase in H+ ions leads to the solution becoming more acidic, as measured by a decrease in pH. Examples of common acids include hydrochloric acid (HCl) and sulfuric acid (H2SO4).

Nucleic acids are polymers made of nucleotides. They are responsible for storing and transmitting genetic information in living organisms. There are two types of nucleic acids: DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). DNA carries the genetic instructions for the development, functioning, and reproduction of all known living organisms, while RNA plays a crucial role in protein synthesis. Therefore, nucleic acids are the correct answer as they are the specific polymers made of nucleic acids.