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?
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?
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________?
What is an element? Give an example.
- Similar to an atom
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?
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?
- 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
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
- 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?
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?
What are the momsaccharides?
What are the disaccharides?
What are the polysaccharides?
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
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?
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?
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?
Describe the complementary base paring in RNA.
- Adenine with Uracil
- Cytosine with Guanine
What are the 3 types of RNA?
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