Ch. 2

What is the classification of a solution with a pH of 8.3?

- Alkaline solution. * A pH between 0.0 and 7.0 is acidic. A pH between 7.0 and 14.0 is basic. Therefore, a solution with a pH of 8.3 is an alkaline (or basic) solution.

What holds the sodium and chloride ions together in a chemical bond?

- An electrical attraction between opposite charges. * The transfer of an electron results in ions with opposite charges that are electrically attracted to each other.

How is an ionic bond formed?

- An ionic bond is formed during the complete transfer of one or more electrons from one atom to another.

The four elements that make up about 96% of body matter are ________.

- Carbon, Oxygen, Hydrogen, Nitrogen.

Which of the following is TRUE regarding the pH of a solution?

- The more hydrogen ions in a solution, the more acidic the solution is.

Energy Matter Mass Weight

- Can be measured only by its effects on matter. - Anything that occupied space and has mass. - Although a man who weighs 175 pounds on Earth would be lighter on the moon and heavier on Jupiter, his mass would not be different. - Weight is a function of, and varies with, gravity.

Cation Neuron Atom Molecule

- Electronically charged particle due to loss of an electron. - Neutral subatomic particle. - Smallest particle of an element that retains its properties. - Small particle of a compound that still retains its properties.

Lipids are a poor source of stored energy.

- False.

Organic compounds are covalently bonded and they always contain oxygen.

- False. * Organic compounds are covalently bonded and they always contain carbon; they often contain oxygen as well.

Which property of water is demonstrated when we sweat?

- High heat of vaporization.

A 23-year-old male was riding his road bike in 100-degree heat, when he suddenly became nauseated and weak. He called 911 from his cell phone. When the ambulance came, the paramedics started intravenous therapy for severe dehydration. Which physical property and which physiological role of water caused the dehydration, and why?

- High heat of vaporization; water was lost when evaporating from the skin to cool the body.

Kidneys play a major role in helping to maintain proper levels of Na+ and K+ ions in the blood. If the kidneys fail to function properly, one of the direct consequences would be_________.

- Impaired nerve impulse transmission. * Salts are ions that contribute to the ability of nerves to conduct an electrical current.

Salts are always ________.

- Ionic compounds.

The pH scale ________.

- Is based on the concentration of hydrogen ions in a solution. * The pH scale, which ranges from 0 to 14, is a logarithmic scale based on the concentration of hydrogen ions in a solution.

Mechanical Energy Chemical Energy Radiant Energy Electrical Energy

- Legs moving the pedals of a bicycle. - When the bonds of ATP are broken, energy is released to do cellular work. - Energy that travels in waves. Part of the electromagnetic spectrum. - Represented by the flow of charged particles along a conductor, or the flow of ions across a membrane.

Which of the following elements is necessary for proper conduction of nervous impulses?

- Na (Sodium).

The genetic information is coded in DNA by the ________.

- Sequence of the nucleotides.

Which of the following is the major positive ion outside cells?

- Sodium.

Which of the following best defines covalent bonds?

- The bond formed when shared electrons occupy a single orbital common to both atoms within a molecule. * Electron sharing produces molecules in which the shared electrons occupy a single orbital common to both atoms, which constitutes a covalent bond.

A 65-year-old patient came to the emergency room with complaints of severe heartburn unrelieved by taking a "large handful" of antacids. Would you expect the pH to be relatively high, low, or normal for the patient's stomach contents, and why?

- The pH would be high. Antacids are basic, and too many antacids would result in a relatively alkaline state.

A chemical reaction in which bonds are broken is usually associated with ________.

- The release of energy.

What is the most significant factor in the formation of a covalent bond?

- The sharing of electron pairs between two atoms. * Covalent bonds are formed by the sharing of electrons between two reactive atoms.

What does CH4 mean?

- There is one carbon and four hydrogen atoms.

Which of the following is not considered a factor in influencing a reaction?

- Time.

What are the two fundamental roles of DNA?

- To provide the instructions for protein synthesis, and replicate itself before cell division. * DNA has two fundamental roles: (1) to replicate itself before the cell divides, ensuring that all genetic information in the descendant cells is identical; and (2) to provide the basic instructions for building every protein in the body.

All organic compounds contain carbon.

- True.

Current information suggests that omega-3 fatty acids decrease the risk of heart disease.

- True.

The lower the pH, the higher the hydrogen ion concentration.

- True.

What is the most abundant and important inorganic compound in living material?

- Water. * Water is the most abundant and important inorganic compound because of its high heat of vaporization, polar solvent properties, high heat capacity, reactivity, and cushioning properties.