Ch. 2 Chemical Composition of the Body

Question 1

Molecules bond because they don’t like to be ____.

Answer 1

Unpaired

Question 2

Unpaired electrons are called ____ ____.

Answer 2

Free radicals

Question 3

Covalent Bonds

Answer 3

Share a pair of electrons; require energy to break

Single, double, and triple bonds (triple covalent is about as molecularly strong as we’re going to get)

Polar (positive and negative end) versus non polar (no region of charge) molecules

Question 4

Polar bond vs Nonpolar bond

Answer 4

Polar: charges aren’t evenly distributed, causing + and - ends

Nonpolar: not water soluble, no charge

Question 5

Ionic bonds

Answer 5

Atoms gain or lose electrons from neighboring atoms

Opposite charges attract

Question 6

Hydrogen bonds

Answer 6

Weak and partial

Water surface tension

Important in DNA structure

Question 7

Van der Waals forces

Answer 7

Weak and nonspecific

Question 8

Hydrogen bonding between adjacent molecules creates ____ ____.

Answer 8

Surface tension

Question 9

Aqueous

Answer 9

Water-based

Question 10

Solution

Answer 10

Solute dissolved in solvent ex: sweet tea.

Solute (sugar) dissolved in solvent (tea)

Question 11

Solubility

Answer 11

Ease of dissolving

Question 12

Hydrophilic

Answer 12

Dissolves in water, highly soluble

Question 13

Hydrophobic

Answer 13

Does NOT dissolve in water (ex: oil and water), low solubility

Question 14

pH

Answer 14

Measure of the concentration of free H+

Question 15

Acid

Answer 15

Contributes to H+ solution

Question 16

Buffer

Answer 16

moderates changes in pH in blood plasma, pH is stabilized by bicarbonate (HCO3-)

Question 17

How do lungs and kidneys help to maintain pH?

Answer 17

Lungs maintain CO2 levels

Kidneys maintain bicarbonate levels

Question 18

Humans function on the slightly ___ side of the pH scale.

Answer 18

Basic (7.35-7.45)

Question 19

pH: What’s the Acidic range?

Answer 19

1-6

Question 20

pH: What number on the pH scale is Neutral?

Answer 20

7

Question 21

pH: What’s the Basic range?

Answer 21

8-14

Question 22

Carbohydrates (CHO)

Answer 22

Most abundant biomolecule; carbon + water

Monosaccharides (glucose)

Disaccharides (2 glucose)

Polysaccharides (many glucose)

Question 23

Why are CHOs important?

Answer 23

Cellular recognition and fuel source

Question 24

What is this structure?

Answer 24

a CHO

Question 25

What is this structure?

Answer 25

a Polysaccharide

Question 26

Lipids

Answer 26

Carbon and hydrogen (NO water) Backbone of glycerol and 1-3 fatty acids Nonpolar Fats (animal, solid at room temperature) Oil (plant, liquid at room temperature) Saturation refers to double bonds

Question 27

Is this a saturated or unsaturated fatty acid?

Answer 27

Saturated

Question 28

Is this a saturated or unsaturated fatty acid?

Answer 28

Unsaturated (has double bonds where hydrogen has been lost)

Question 29

What is the backbone in a triglyceride?

Answer 29

Glycerol

Question 30

Lipid-Related Molecules: Eicosanoids

Answer 30

Important for regulating cell function

Question 31

Lipid-Related Molecules: Steroids

Answer 31

Cholesterol is the primary source of steroids in the human body Need cholesterol for hormone signaling

Question 32

Lipid-Related Molecules: Phospholipids are important in ____ \_\_\_\_.

Answer 32

Cellular Structure

Question 33

What is this structure?

Answer 33

Phospholipid

Question 34

What is this structure?

Answer 34

A protein

Question 35

Discuss proteins

Answer 35

Made up of amino acid (AA) building blocks Enzymes Membrane transporters Signal molecules Receptors Binding proteins Immunoglobulins Regulatory proteins

Question 36

What is this structure?

Answer 36

Peptide bond

Question 37

What type of protein structure is this?

Answer 37

Primary

Question 38

What type of protein structure is this?

Answer 38

Secondary structure (alpha helix)

Question 39

What type of protein structure is this?

Answer 39

Secondary (beta-pleated sheet)

Question 40

What type of protein structure is this?

Answer 40

Tertiary

Question 41

What type of protein structure is this?

Answer 41

Quaternary

Question 42

Secondary vs Tertiary vs Quaternary protein structures

Answer 42

**Secondary**: interactions happening in proximal parts of chain, starts to take shape **Tertiary**: starting to fold back on itself to make intricate shapes **Quaternary**: 2 different peptide chains came together to make a structure

Question 43

Issues with protein structure can lead to \_\_\_\_.

Answer 43

Disease (ex: resulting from protein folding incorrectly) Complex structure = complex function

Question 44

What determines the shape/structure of proteins?

Answer 44

Hydrogen bonds are critical in determining structure/shape of proteins

Question 45

Nucleic Acids

Answer 45

Important for DNA (chain of nucleic acids) Important for ATP (cellular energy)

Question 46

What do these bases make up?

Answer 46

DNA

Question 47

DNA vs RNA

Answer 47

DNA contains: deoxyribose thymine RNA contains: ribose uracil