Chapter 2 - Chemistry of Life Flashcards
What are the three parts of an atom and how are they charged? 2.1
Proton - positive
Neutron - neutral
Electron - negative
Which two parts are located in the center of an atom? 2.1
Protons and Neutrons
What is an electrically balanced atom? 2.1
Atoms that have an equal number of protons and electrons
What is an element? 2.1
A substance that is made up of only one type of atom
How do you find the number of neutrons? 2.1
Subtract the atomic number from the atomic weight
What are isotopes? 2.1
Atoms of the same element with different numbers of neutrons but the same number of protons
What can isotopes be used for? 2.1
Cancer treatment and fossil dating because of the radiation
What is a compound? 2.1
A substance made of the bonded atoms of two or more different elements
What is a molecule? 2.1
A group of atoms held together by covalent bonds
What are covalent bonds? 2.1
Bonds that occur when valence electrons are shared between atoms
What is a charged atom called? 2.1
Ion
How many electrons can be in each level? 2.1
1 - 2
2 - Max. 8
3 - Max. 8
What are valence electrons? 2.1
Electrons in the outermost shell or level
- Atoms will combine to become more stable in the valence shell
What is a hydrogen bond? 2.2
An attraction between a slightly positive hydrogen and a slightly negative atom, often oxygen or nitrogen
Why does an ion have an electrical charge? 2.1
Electrons in an atom’s outermost energy level change
What is an ion? 2.1
An atom that has gained or lost one or more electrons
How does an ionic bond form? 2.1
Through the electrical force between oppositely charged ions
What is cohesion? 2.2
Attraction of the particles of the same substance
What is adhesion? 2.2
Adhesion of the particles of different substances
What is a solution? 2.2
Mixture of substances that is the same throughout
What is a solvent? 2.2
1/2 of a solution
Substance that is present in the greater amount and dissolves another
What is a solute? 2.2
1/2 of a solution
Substance that dissolves in a solvent
What are acids? 2.2
Compounds that form hydrogen ions when dissolved in water
What are bases? 2.2
Compounds that reduce the concentration of hydrogen ions and increase in the concentration of hydroxide ions
What is pH? 2.2
Measure of how acidic and basic a solution
Based on hydrogen ion concentration
What is a buffer? 2.2
A substance that reacts to prevent pH changes in a solution
What are 3 fundamental structures of carbon-based atoms? 2.3
Straight chain
Branched chains
Rings
What are monomers? 2.3
Subunits in a complete molecule, and link together to form a polymer (macromolecule)
What are polymers? 2.3
A macromolecule made up of many monomers
How are monomers formed? 2.3
By the process of condensation synthesis ( H2O is released as the molecules bond together)
How are monomers broken down? 2.3
By the process of hydrolysis ( H2O is added to the molecule to break the bond)
How are polymers formed? 2.3
By the process of condensation ( H2O is removed as the molecules bond together )
How are polymers broken down? 2.3
By the process of hydrolysis ( H2O is added to the molecule to break the bond )
What do plants convert and store excess sugars as? 2.3
Starches
What do animals convert and store excess sugars as? 2.3
Glycogen
What are types of monosaccharides? 2.3
Glucose, Fructose, Galactose (simple sugar)
What are disaccharides? 2.3
2 sugars bonded together
ex. sucrose, maltose, lactose
What are polysaccharides? 2.3
Many sugars bonded together
ex. starch, glycogen, cellulose, chitin
What are carbohydrates? 2.3
- Molecules composed of carbon, hydrogen, and oxygen and include sugars and starches
- Can be broken down to provide a source of useable chemical energy for cells
- A major part of cell structure
What are the three types of carbohydrates? 2.3
Monosaccharides
Disaccharides
Polysaccharides
What are lipids? 2.3
Nonpolar molecules that include fats, oils, waxes, and cholesterol
What are fatty acids? 2.3
Chains of hydrogen atoms bonded to carbon atoms
What are the two different types of fatty acids? 2.3
Saturated
Unsaturated
What is a protein? 2.3
A polymer made out of monomers called amino acids
What are amino acids? 2.3
Molecules that contain carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur
What does a triglyceride have? 2.3
- 3 fatty acids
- A glycerol molecule
- No phosphate group
What are saturated fats? 2.3
- Contain fatty acids in which all carbon-carbon bonds are single
- Have maximum number of hydrogen atoms possible
- Animal, solid, fats
What are unsaturated fats? 2.3
- Contain fatty acids with at least one carbon - carbon double bond
- Have double bonds which make kinks
- Plant, liquid, oils
What does a phospholipid contain? 2.3
Glycerol, 2 Fatty Acids, Phosphate Group - Head
Fatty Acids - Tails
What determines the number of covalent bonds that an atom can form? 2.1
Number of unpaired electrons in the outermost shell
What types of substances dissolve easily in water? 2.2
Polar
What types of substances do not dissolve easily in water? 2.2
Nonpolar
What are 3 parts found in every amino acid? 2.3
Hydrogen Atom
Amino Group
Carboxyl Group
What are nucleic acids? 2.3
Polymers that are made up of monomers called nucleotides
What are amino acids linked by? 2.3
Covalent bonds called peptide bonds
What do proteins do? 2.3
Provide structure
Make up enzymes (initiate chem. reactions), hemoglobin and antibodies
What are dipeptides and polypeptides? 2.3
Two or many amino acids linked together by peptide bonds
How many different amino acids are found in proteins? 2.3
20
What are the importances of nucleic acids? 2.3
Contain the instructions to make proteins
DNA stores information for putting amino acids together to make proteins and RNA helps to build proteins
DNA is the basis of genes and heredity
What do chemical reactions do? 2.4
Change substances into different substances by breaking and forming chemical bonds
What are reactants? 2.4
Substances that change during the chemical reaction
What are products? 2.4
Substances that are made by a chemical reaction
What is bond energy? 2.4
Energy that is needed to break bonds between the reactant compounds
What is equilibrium? 2.4
When reactants and products are made at the same rate
What is activation energy? 2.4
Amount of energy that needs to be absorbed in order for a chemical reaction to start
What are the two types of chemical reactions? 2.4
Endothermic
Exothermic
What is exothermic energy? 2.4
Exothermic—more energy is released in the reaction than was absorbed
Bond energy of products is lower than the bond energy of the reactants
Usually released as heat or light
Ex. Flashes of lights from animals, heat released from cellular respiration
What is endothermic energy? 2.4
Endothermic—more energy is absorbed in the reaction than was release
Products have higher bond energy than the reactants
Ex. Photosynthesis, absorb sunlight to make simple sugars and carbs
What is a catalyst? 2.5
A substance that decreases the activation energy needed to start a chemical reaction, and as a result, also increases the rate in which a chemical reaction occurs
What are enzymes? 2.5
Catalysts for chemical reactions in living things
What are substrates? 2.5
Specific reactants that enzymes act on
Lock and key model
What is an active site? 2.5
Places where substrates and enzymes combine
More about enzymes
2.5
- Proteins
- Recycle-able
- Involved in almost every process
- Must have a certain pH and temperature to function
- Usually end in “ase” such as lactase, maltase, sucrase
What’s the difference between DNA and RNA? 2.5
DNA stores genetic information in cells, and RNA helps to build the proteins
for which DNA codes.
