Lecture 2

Question 1

The chemical elements
-_____ elements have biological roles
-___ elements= 98.5% of body weight
-CHONPS:

Answer 1

-24
-6
-main and biological significant elements in our body:
Carbon
Hydrogen
Oxygen
Nitrogen
Phosphorus
Sulfur

Question 2

Ions:
Ionization:
Anion:
Cation:

Answer 2

-charged particle (atom or molecule) w/ unequal number of protons and electrons
-transfer of electrons from one atom to another
-particle that has a net negative charge (due to gain of electrons)
-particle that has a net positive charge (due to loss of electrons)

Question 3

Ions with opposite charges are ________ to each other

Answer 3

attracted

Question 4

Electrolytes:

Electrolyte importance:
-chemical reactivity, ________ ________, electrical excitability of _________ and _________
-electrolyte balance is one of the most important considerations in _____________ (imbalance 2323s can lead to ____ or ________)

Answer 4

substances that ionize in water and form solutions capable of conducting electric current
-osmotic effects; nerves; muscle
-patient care; coma; cardiac arrest

Question 5

molecule

Answer 5

particle composed of two or more atoms united by a chemical bond

Question 6

compound

Answer 6

molecule composed of two or more different elements

Question 7

Molecular formula

Answer 7

identifies constituent elements and how many atoms of each are present

Question 8

Structural formula

Answer 8

identifies location of each atom

Question 9

Isomers

Answer 9

molecules with identical molecular formulas but different arrangements of atoms

Question 10

Chemical bonds (Important types)
-_________
-_________
-_________
-_________

Answer 10

ionic bonds
covalent bonds
hydrogen bonds
van der walls forces

Question 11

Ionic bonds

Answer 11

attraction of a cation to an anion
-easily broken by water

Question 12

Covalent Bonds

Answer 12

atoms share one or more pairs of electrons

Question 13

Non-polar covalent bond

Answer 13

electrons shared equally

Question 14

Polar covalent bond

Answer 14

electrons shared unequally

Question 15

Hydrogen bonds:
-Weak attraction between a slightly ________ hydrogen atom in one molecule slightly _________ oxygen or nitrogen atom in another atom
-Important to physiology:
-give water many of its properties
-important in maintaining ______ structure and _______ structure
-involved in enzyme substrate interactions

Answer 15

positive; negative
protein; DNA

Question 16

Van der Waals Forces
-Weak, brief attraction between _______ atoms
- Fluctuation in electron density within an atom creates _________ for a moment, and attracts adjacent atom for a very short time
-Only ___% as strong as a covalent bond, but play important role in physiology (e.g. _________)

Answer 16

-neutral
-polarity
-1; protein folding