-
Briefly describe the three states of matter
- Three states:
- Solid (definite shape and volume)
- Liquid (definite volume, variable shape) Gaseous (variable shape and volume)
-
What are atoms? What are "elements"?
Atoms: building blocks
Elements: matter made of similar atoms
-
Name the four elements that compose 96% of body mass
- Nitrogen
- Carbon
- Oxygen
- Hydrogen
-
Describe the structure of atoms
- very small = <0.1 nm or 0.0000001 cm
- made up of protons, neutrons, and electrons
-
How do different elements and isotopes differ in terms of atomic number, mass number, and atomic weight?
Isotope: structural variation of an atom that has the same # of protons, but different # of neutrons and weight
-
What are radioisotopes? How are they used in modern medicine?
- Isotopes that are unstable and spontaneously decompose into more stable forms
- Nuclear medicine: use of radioisotopes to diagnose and treat disease
-
Briefly explain what are molecules, compounds, and mixtures, and how they differ from one another.
- No chemical bonds in a mixture (physical properties of molecules are unchanged)
- Mixtures are separated by physical means (evaporation, filtering, freezing)
- Compounds are separated by chemical means (breaking bonds)
-
What part of atomic structure determines the reactivity of elements?
# of electrons in outer “valence” shell determines reactivity
-
What are hydrogen bonds? In what type of molecules do hydrogen bonds form? How are hydrogen bonds different from ionic and covalent bonds?
Form when partial positive charge (δ+) of a hydrogen atom attracts the partial negative charge (δ-) of a neighboring atom common in polar molecules form weak attractions compared to ionic and covalent bonds responsible for surface tension, intramolecular bonds (DNA, protein)
-
Name and briefly describe the properties of water that make it vital to life
- polar solvent properties- universal solvent- body’s transport medium
- thermal properties- high heat capacity- high heat of vaporization
- reactivity- hydrolysis = breaks bonds- dehydration synthesis = forms bonds
- reactivity- hydrolysis = breaks bonds- dehydration synthesis = forms bonds
-
Describe the structure of carbohydrates, with reference to the difference between mono-, di-, and poly-saccharides, and to hydrolysis and dehydration reactions
rings of “hydrated” carbon biological roles: - fuel source - structural role (DNA backbone) can be in the form of monosaccharides, disaccharides, or polysaccharides
-
Saturated vs. Unsaturated Triglycerides
- Saturated: single covalent bond between carbon atoms fatty acid chains are straight solid at room temperature increase risk of heart disease
- Unsaturated: one or more double bonds between carbon atoms fatty acid chains are kinked liquid at room temperature decrease risk of heart disease
-
What are Phosopholipids
glycerol + 2 fatty acids + 1 phosphate group polar (head) and non-polar (tail), or “amphipathic” biological functions - cellular membranes
-
What are Steriods
4 interlocking rings of carbon some examples: - cholesterol (cell membrane structure) - estrogen and testosterone (sexual functions) - bile salts (lipid digestion) - vitamin D (bone growth)
-
What are Proteins
Precise assembly of amino acids with peptide bond, sequence determined by genetic code (DNA)
-
Describe the two main classes of proteins and be able to name examples of each
Fibrous: extended and strand-like, insoluble in water, and very stable structural (collagen and keratin) movement (actin and myosin)
Globular: compact, spherical, water-soluble, less stable regulation (hormones) defense (antibodies) transport (hemoglobin) catalysts (enzymes)
-
What are Mistakes
Primary sequence can disrupt all structural levels of a protein
-
What is Protien denaturation
Wrong physical or chemical (pH, temperature) conditions can cause protein denaturation
-
Anything ending in "Ases" means what?
It meas that the chemical reaction has or is going to be catalized
-
What Catalysts?
Catalysts: accelerate the rate of biochemical reactions, by lowering activation energy required for reaction
-
Adenosine Triphosphate(ATP)
- “Energy currency” of living systems
- Fuel molecules (ex. glucose, lipids) contain too much energy to be used at one time, slowly broken down Energy released used to make smaller packets of energy (ATP)
- Energy stored in ATP is close to what is needed for most biochemical reactions
|
|
