Lecture 2 Flashcards
What are isotopes?
Variations of elements
Same # of protons and electrons but different neutron #’s= different mass
What is an ionic bond?
One atom loses electrons, others gain= ion
Opposites attract- Ionic bond
What is a covalent bond?
Strongest bond
Two atoms share one or more pairs of electrons
What is a hydrogen bond?
Between molecules involving hydrogen
Made possibly by uneven covalent bonding
Weakest bond
What is a synthesis reaction?
New bonds are formed
Endergonic (net energy in)
What is a dehydration synthesis reaction?
Molecules are made by removing water
What is a decomposition reaction?
Bonds are broken
Exergonic (net energy out, exit)
What is a hydrolysis reaction?
Breaking down molecules with water
What is catabolism?
Decomposition reactions in cells
What is anabolism?
Synthesis (building) reactions in cells
What is an exchange reaction?
Part decomposition and synthesis
What are the characteristics of inorganic molecules?
Typically lack carbon
Simple
Salts, acids, bases
H2O, O2
What are organic molecules?
Always contain carbon
Complex
Sugars, proteins, Nucleic acids, lipids
What is a polar molecule?
Any molecule having unequal distribution of charge
What are properties of water related to polarity?
Cohesion and adhesion
High specific heat capacity
What is cohesion?
Attraction of molecules for other molecules of same kind
What is adhesion?
Attraction of molecules of one kind for molecules of different kind
What is a cation?
Positively charged ion
What is an anion?
Negatively charged ion
What is the best ph for organisms?
6.5-8.5
How are organic molecules broken down?
Hydrolysis
What are the 3 major groups of carbs?
Monosaccharide, disaccharide, polysaccharide
What are examples of polysaccharides?
Cellulose- algae cell walls
Chitin- cell wall of fungi
Starch- produced by plants and used as food by us
What is a characteristic of lipids?
They are hydrophobic
What are simple lipids?
Triglycerides which contain glycerol and 3 fatty acids