Seeley’s Essentials of Anatomy & Physiology - Chapter 2 Flashcards

Flashcards covering the chemical basis of life, including atomic structure, chemical bonding, reactions, pH, and the major classes of organic molecules.

How is matter defined?

Anything that occupies space and has mass (solid, liquid, or gas).

What is the difference between mass and weight?

Mass is the amount of matter in an object, while weight is the gravitational force acting on that object.

What is an atom?

The smallest particle of an element that contains protons, electrons, and neutrons.

Where is the proton located and what is its charge?

It is a positive charged particle located inside the nucleus.

Where is the neutron located and what is its charge?

It is a neutral charged particle located inside the nucleus.

Where is the electron located and what is its charge?

It is a negative charged particle located outside the nucleus.

How is the atomic number of an atom determined?

It is the number of protons in each atom.

How is the mass number of an atom determined?

It is the total number of protons and neutrons in each atom.

What are valence shell electrons?

The outermost electrons of an atom that are transferred or shared during the formation of chemical bonds.

What is an ion?

A charged atom formed because of a donation or gain of electron(s), such as $Na^+$.

What is ionic bonding?

A bond that occurs when there is an attraction between two oppositely charged ions, such as $NaCl$.

What is covalent bonding?

A bond that occurs when atoms share one or more pairs of electrons.

What is the difference between polar and nonpolar covalent bonds?

Polar covalent bonds involve unequal sharing of electrons resulting in an asymmetrical charge, while nonpolar molecules have a symmetrical electrical charge.

What is a hydrogen bond?

A weak bond formed when the positive end of one polar molecule is attracted to the negative end of another polar molecule.

What is the difference between a molecule and a compound?

A molecule is 2 or more atoms chemically combined (e.g., $H_2O$), while a compound is a chemical combination of 2 or more different types of atoms (e.g., $NaCl$).

In a chemical reaction, what are reactants and products?

Reactants are substances that enter into the reaction, and products are substances that result from the reaction ($A + B \rightarrow C + D$).

What is a synthesis reaction?

A reaction that builds a new molecule and requires energy, such as $ADP + P \rightarrow ATP$.

What is a decomposition reaction?

A reaction that breaks down a molecule and releases energy, such as $ATP \rightarrow ADP + P$.

What characterizes an exchange reaction?

It is a combination of synthesis and decomposition reactions, such as $HCl + NaOH \rightarrow NaCl + H_2O$.

What is equilibrium in a reversible reaction?

When the rate of product formation equals the rate of reactant formation.

What is the difference between kinetic and potential energy?

Kinetic energy is energy in motion, whereas potential energy is stored energy.

What is chemical energy?

A form of potential energy stored in chemical bonds, such as those in glucose or $ATP$.

What three factors influence the rate of a chemical reaction?

Concentration of reactants, temperature, and the presence of a catalyst.

How is an acid defined in terms of protons and pH?

An acid is a proton ($H^+$) donor with a pH below $7$.

How is a base defined in terms of protons and pH?

A base is a proton ($H^+$) acceptor with a pH above $7$.

What is the primary difference between inorganic and organic chemistry?

Inorganic chemistry deals with substances that do not contain carbon, while organic chemistry study carbon-containing substances (with some exceptions like $CO_2$).

What are the four major groups of organic molecules essential to life?

Carbohydrates, lipids, proteins, and nucleic acids.

What are the building blocks of carbohydrates?

Monosaccharides, which are simple sugars like glucose and fructose.

What is a polysaccharide and what are some examples?

A molecule made of many sugars, such as starch, grain, vegetables, and glycogen.

What are the functions of lipids?

Long term energy storage, insulation against heat loss, protective cushioning for organs, and cell membrane structure (cholesterol).

What is the difference between saturated and unsaturated fats?

Saturated fats have single covalent bonds between carbon atoms (e.g., beef, butter), while unsaturated fats have one or more double covalent bonds (e.g., olive oil).

What are the building blocks of proteins?

Amino acids (there are 20 different naturally occurring types).

What is protein denaturation?

When hydrogen bonds maintaining a protein's shape are broken, making it nonfunctional; caused by high temperatures or improper pH.

How do enzymes affect chemical reactions?

They act as organic catalysts that increase the reaction rate by lowering the energy of activation.

What are the building blocks of nucleic acids?

Nucleotides, which are composed of a nitrogen base, a phosphate, and a 5-carbon sugar.

What is the structure of DNA?

A double-stranded helix where phosphate groups connect sugars, and nitrogen bases are joined by hydrogen bonds ($A$ to $T$, $C$ to $G$).

What is Adenosine Triphosphate (ATP) often called?

The energy currency of cells.