1.1 Chemistry of Living Systems

Question 1

isotope

Answer 1

atoms of the same element that have the same number of protons, different number of neutrons

Question 2

radioisotope

Answer 2

an unstable isotope that undergoes nuclear decay over time by emitting radiation

Question 3

molecule

Answer 3

a substance composed of two or more non-metal atoms that are covalently bonded together

Question 4

organic molecule

Answer 4

a carbon-containing molecule in which carbon atoms are nearly always bonded to each other and to hydrogen

Question 5

biochemistry

Answer 5

the branch of science dealing with the properties of biological molecules and the chemical processes that occur within living organisms

Question 6

intramolecular

Answer 6

occurring between atoms within a molecule

Question 7

intermolecular

Answer 7

occurring between atoms of different molecules

Question 8

hydrogen bond

Answer 8

a weak association between an atom with a partial negative charge and a hydrogen atom with a partial positive charge

Question 9

hydrophobic

Answer 9

referring to non-polar molecules that do not have attractive interactions with water molecules

Question 10

hydrophilic

Answer 10

referring to polar molecules that have attractive interactions with water molecules

Question 11

elements

Answer 11

all matter is composed of elements, which cannot be broken down into simpler substances

Question 12

4 essential elements

Answer 12

4 essential elements account for 99% of the atoms found in the human body
- hydrogen 63%
- oxygen 26%
- carbon 9%
- nitrogen 1%
Mineral elements (0.07%)
Trace elements (<0.01)

Question 13

atom

Answer 13

the atom is the smallest particle of an element that maintains the properties of that element
- atomic # = # of protons = # of electrons
- mass # = protons + neutrons