A & P I- Chapter 2- Basic Chemistry

What is an atom?

- The smallest particle to have unique chemical properties.

What are the 3 subatomic particles?

- Proton (+)
- Neutron (o)
- Electron (-)

What are the characteristics of a proton and where are they located?

- Have mass
- Positively charged
- # of protons CANNOT be changed
- Located in the nucleus

What is the relationship between the atomic number of an element and the number of protons it has?

- They are the same

Can the atomic number of an atom change?

- No

What are the characteristics of a neutron and where are they located?

- Have mass
- Do not have a charge
- The # of neutrons an element has CAN change
- Located in the nucleus

Can the number of neutrons an element has change?

- Yes

What are the characteristics of an electron and where are they located?

- Do NOT have a mass
- Negatively charged
- # of electrons an atom has CAN change
- The # of electrons an atom has determines its ability to form bonds with other atoms
- Located in orbits or shells outside of the nucleus

In the native state, the number of electrons an element has is equal to the number of________?

- Protons

What is an element? Give an example.

- Similar to an atom
- Oxygen

How do you calculate the atomic mass of an element?

- # of protons + # of neutrons

Can the atomic mass of an element change? If so, how?

- The AMU can change if the number of neutrons change.

What is an isotope?

- An atom that has a different number of neutrons in the nucleus than what is usually found for that particular element.

What is an ion and how are they formed?

- A charged particle.

What is a molecule?

- A chemical composed of 2 or more atoms held together by a chemical bond.

What is a macromolecule?

- Very large molecules that are composed of many atoms.

What is a chemical bond?

- An attractive force between valence electrons of 2 atoms.

What is a valence electron?

- The electrons in the outermost shell of an atom.

What are the 3 main categories of chemical bonds and which is the strongest?

- Ionic bonds
- Covalent bonds
- Hydrogen bonds

Explain ionic bonds.

- 1 atom donates an electron to another atom that readily accepts it. (OPPOSITES ATTRACT)
- Form between a positively charged cation and a negatively charged anion. (Held together by the attraction between the (-) and (+) charges.
- Molecules with ionic b

What are electrolytes?

- Cations and anions that result when ionic compounds are placed in a solution; then conducting an electric current.

What are covalent bonds?

- Involves the sharing of electrons instead of donating/accepting of electrons. (SHARING IS CARING)
- Strongest of all 3 bonds
- When atoms share 2 pairs of electrons it is called a double bond.

Explain non-polar covalent bonds.

- Involves EQUAL sharing of electrons between 2 atoms

Explain polar covalent bonds.

- Involves UNEQUAL sharing of electrons between 2 atoms.
- Creates "poles" like a magnet or battery.

Explain hydrogen bonds.

- Form between 2 molecules containing polar covalent bonds
- Form between the slight positive charge of one molecule and the slight negative charge of ANOTHER molecule

Do atoms in their native state contain a charge?

- No

Define an anion.

- A negatively charged atom

Define a cation.

- A positively charged ion

What are the 2 types of covalent bonds?

- Non-Polar Covalent Bond
- Polar Covalent Bonds

Differentiate between a "polar covalent bond" and a "non-polar covalent bond". Which is water soluble?

- Polar are UNEQUAL and Non-Polar are EQUAL

In terms of chemistry, what is meant by the the term "polar"?

- There are 2 opposite sides "poles

A carbon atom forms what type of bond?

- Non-polar covalent bond

Is a hydrogen bond formed between 2 different molecules or within one molecule?

- 2 different molecules

Why are hydrogen bonds so important to life?

- They give water many of the properties that we depend on

In terms of a chemical reaction, what is a reactant?

- The starting material

In terms of a chemical reaction, what is a product?

- The ending material

What is the definition of energy?

- The capacity to do work

What are the 2 main types of energy?

- Potential
- Kinetic (energy in motion)

What are they 3 types of potential and kinetic energy in the body?

- Chemical energy
- Electrical energy
- Mechanical energy

What is chemical energy and what is an example in the body?

- a type of potential energy (fuels nearly all the cellular processes of the cell)

What is potential energy and what is an example in the body?

- Energy stored in an object because of its position- "stored energy

What is mechanical energy?

- Energy is energy that has been transferred from one object to another

What is an endergonic reaction?

- Chemical reactions which require an input of energy from another source to proceed

What is an exergonic reaction?

- Reactions that result in the release of energy from the reactants

What are the characteristics of a catabolic reaction?

- Decomposition reactions in which larger substances are broken down into smaller ones

What are the characteristics of an exchange reaction?

- One or more atoms from the reactants are exchanged for another

What are the characteristics of an anabolic reaction?

- Building reactions in which smaller molecules are joined together to build larger molecules

In a chemical reaction, what is meant by oxidation?

- Reactions in which a molecule loses an electron or energy

In a chemical reaction, what is meant by reduction?

- Reactions in which a molecule gains an electron or energy

What are 4 factors that can change the rate of a reaction?

- Presence of enzyme or catalyst
- Concentration of reactants
- Properties of reactants
- Temperature of the reaction

Explain how an enzyme can change the rate of a chemical reaction.

- They lower the energy of activation of a reaction

What are the 4 ways that water helps support life?

- Thermal stability
- Evaporative cooling
- Cushioning and protecting
- Lubricant

What is meant by "heat capacity"?

- Amount of energy/heat needed to increase the temperature of 1 g of a substance by 1 degree Celcius

Why is it important for water to have a high heat capacity and high thermostability?

- It allows our bodies to maintain a stable internal temperature regardless of the external temperature.

Explain the process of evaporative cooling.

- When a water molecule evaporates from the skin, it takes with it all of the energy/heat that it has absorbed, and thus has a cooling effect

What is a solvent?

- A substance that will dissolve other substances

What does it mean if something is hydrophillic?

- "water loving

What does it mean if something is hydrophobic?

- "water hating

What type of molecules are hydrophilic and hydrophobic?

- Hydrophilic- ones with a charge
- Hydrophobic- contain non-polar covalent bonds

Define pH.

- a measure of the hydrogen ion concentration [H+] of a solution

Define an acid.

- pH < 7 (H+ donor)

Define a base.

- pH > 7 (H+ acceptor)

Define a buffer.

- A chemical that can act as either an acid or a base to maintain a certain pH

What is the relationship between pH and hydrogen ion concentration?

- The lower the pH, the higher the [H+].

What is the pH range of blood and body fluids?

- 7.35-7.45

Why is it important to maintain a normal body pH?

- Drastic changes can affect the body's ability to carry out metabolic reactions. change the activity/effectiveness of drugs, and change the muscle activity causing tremors, paralysis, and death.

What are the 4 main groups of organic macromolecules in the body?

- Carbohydrates
- Lipids
- Proteins
- Nucleotides

What are the momsaccharides?

- Glucose
- Fructose
- Galactose

What are the disaccharides?

- Sucrose
- Lactose
- Maltose

What are the polysaccharides?

- Glycogen
- Starch
- Cellulose

What monosaccharides make up the disaccharides?

- Sucrose = glucose + fructose
- Lactose = glucose + galactose
- Maltose = glucose + glucose

Define, give the significance of, and state where you would find glycogen.

- Large chains of glucose molecules hooked together
- Made mainly in the liver and muscle
- Maintains BGL

Define, give the significance of, and state where you would find starch.

- Energy stored in plants
- Made only by plants

Define, give the significance of, and state where you would find cellulose.

- A structural CHO made only by plants
- Used by plants to strengthen the cell wall
- The most abundant CHO on earth
- Important in our diets as fiber (cant digest it)

What are the 4 main categories of lipids found in the body?

- Fatty Acids
- Triglycerides
- Phospholipids
- Steroids

What are the 3 types of fatty acids found in the body and what are the structures of each?

- Saturated FA ( contains as many H atoms as possible)
- Monosaturated FA (contain a single C=C double bond but does not contain as many H atoms)
- Polysaturated FA (2 or more C=C double bonds)

Describe a triglyceride.

- Made up of a 3-C glycerol backbone with 3 FA attached to it
- Metabolized for energy

What is the primary function of triglycerides in the body?

- Energy storage and insulation and cushioning for organs

At room temperature, are saturated FA solid or liquid? Unsaturated FA?

- Sat FA- Solid (Butter)
- Unsat FA- Liquid (Oil)

Describe the structure of a phospholipid.

- Hydrophilic head and hydrophoblic tail
- Similar to Triglycerides, but a fatty acid is replaced with a phosphate group

What is the primary importance of phospholipids?

- Provide structure for cell membranes

What is the "parent steroid" in the body?

- Cholesterol

Describe the basic structure of a protein.

- Various combinations of amino acids make up proteins

Describe each of the 4 levels of protein structure.

- Primary = determined by sequence of AA
- Secondary = coiling or folding of the AA chain due to the formation of hydrogen bonds (alpha helix or beta pleated sheet)
- Tertiary = coiling or folding of the AA chain based on interaction the hydrophilic/phobi

What is meant by denaturing a protein? What 2 conditions will lead to that?

- When proteins change shape or "unravel"
- Excessive heating or changes in pH

What are the 3 parts of a nucleotide?

- Nitrogenous base
- 5-carbon sugar
- Phosphate group(s)

What are 3 types of compounds composed of nucleotides?


What does "DNA" stand for?

- Deoxyribonucleic Acid

Describe the structure of DNA.

- 2 long chains of nucleotides that are linked otgether and twiseted to form a double helix

What are 4 types of nitrogenous bases found in DNA?

- Adenine
- Guanine
- Cytosine
- Thymine

What is meant by "complementary base paring" in DNA?

- Adenine with Cytosine
- Guanine with Thymine

What does "RNA" stand for?

- Ribonucleic Acid

Describe the structure of RNA?

- 5-carbon sugar

What are the 4 nitrogenous bases found in RNA?

- Adenine
- Guanine
- Cytosine
- Uracil

Describe the complementary base paring in RNA.

- Adenine with Uracil
- Cytosine with Guanine

What are the 3 types of RNA?

- mRNA
- tRNA
- rRNA

What are the functions of the 3 types of RNA?

- mRNA = messenger (copy genetic instructions for a specific protein that is carried to the nucleus and ribosomes)
- tRNA = transfer (transports the correct AA to the ribosome during translation)
- rRNA = Ribosomal (part of the ribosome)

What type of polymers are DNA and RNA?

- Nucleic Acids