Quiz 2 CHEMISTRY

Question 1

Matter

Answer 1

• as it pertains to our study of the body, matter is anything that has mass and occupies space (has volume)
• exists as SOLID, LIQUID, or GAS

Question 2

ATOM

Answer 2

• the smallest component of matter identified in chemical reactions
• 92 different naturally occurring atoms termed ELEMENTS

Question 3

ELEMENTS

Answer 3

• the “stuff” that makes up our world
• 26 elements involved in maintaining human life, 13 are trace elements, the other 13 make up 99% of our corporeal matter

Question 4

13 most abundant elements in the body

Answer 4

C
Ca
Cl
Fe
H
I
K
Mg
N
Na
O
P
S

Question 5

MOLECULES/COMPOUNDS

Answer 5

two or more elements chemically bonded together

Question 6

Covalent Bond (polar and non-polar)

Answer 6

• stable bond formed by sharing electrons
• unequal sharing termed POLAR covalent
• equal sharing termed NON-POLAR covalent

Question 7

Ionic Bond

Answer 7

• relatively weak, unstable bond formed by one element donating electrons to the other
• this results in charged atoms called IONS that dissociate easily in solution into what is known as electrolytes

Question 8

Electrolytes

Answer 8

the basis for electrical activity in our nervous and muscle tissue

Question 9

Acids

Answer 9

compounds that donate a hydrogen ion (H+); a common acid is HCl

Question 10

Bases

Answer 10

compounds that donate a hydroxyl ion (OH-); a common base is KOH

Question 11

Acids and Bases

Answer 11

• when an acid and base are mixed they form a salt and water. Salts are electrolytes. Using this example, the reaction looks like:
  HCl + KOH —> KCl + H2O

(the KCl dissociates into the K+ and the Cl- ions

Question 12

pH

Answer 12

• a measure of how acidic or alkaline (basic) something is; generally measured on a 0-14 scale
• normal body pH is 7.35-7.45

Question 13

Macromolecules

Answer 13

• there are 4 classes of relatively large molecules that comprise about 95% of our body: Carbohydrate, Lipid, Protein, and Molecule

Question 14

Carbohydrates

Answer 14

C,H,O
- exist as monosaccharides (simple sugars), disaccharides, and polysaccharides
Functions: energy source/storage, structural stability, DNA/RNA

Question 15

Lipids

Answer 15

C,H,O
- exist as triglycerides, phospholipids, and steroids
Functions: energy source/storage, membrane components, steroid hormones

Question 16

Proteins

Answer 16

C,H,O,N
- exist in a myriad of forms, small and large, all composed of AMINO ACIDS e.g. enzymes, membrane receptors, and hormones
Functions: energy source, coding for structure or function

Question 17

Nucleotides

Answer 17

C,H,O,N,P
- exist in nucleic acids (DNA,RNA) and ATP
Functions: energy currency, coding, signaling, aiding metabolism

Question 18

Water

Answer 18

• is a polar covalent compound vital for maintaining homeostasis, acting as a universal solvent and transporter
• found within our cells as intracellular fluid
• as extracellular fluid it is part of our blood, lymph, and interstitial fluid (fluid surrounding our cells), as well as in our secretions and excretions
• regulating the chemistry of these fluids is essential to sustain life, where moderate imbalance results in disease and severe imbalance results in death

Question 19

Energy

Answer 19

• the ability to do work or put matter into motion
• exists in 2 basic forms: either stored or changing
• in biochemistry, stored energy is the potential that exists as a result of the bond that holds molecules together and it is referred to as CHEMICAL ENERGY

Question 20

Chemical Energy

Answer 20

• stored energy is the potential that exists as a result of the bond that holds molecules together
• it is utilized (changed) through chemical reactions that occur in our cells and tissues
• the utilization of chemical energy may result in the creation of a new molecule (chemical), or it may be converted into a different form of energy such as heat
• energy cannot be created or destroyed, it simply changes form

Question 21

ATP

Answer 21

(adenosine triphosphate) the chemical energy used by our cells