Biology Chap 2

Question 1

hydrophilic

Answer 1

water loving, polar good solvents

Question 2

hydrophobic

Answer 2

water fearing, nonpolar arrange themselves in a manner to minimize their contact with H20

Question 3

hydrophobic effect

Answer 3

polar molecules like water exclude nonpolar ones, drive such processes like the formation of all membranes, and the folding of proteins

Question 4

organic molecules

Answer 4

carbon containing molecules, carbon is essential to life, it has the ability to combine with many other elements to form a wide variety of molecules

Question 5

Proteins

Answer 5

provide structural and act as catalyst that facilitate chemical rx

Question 6

Nucleic Acid

Answer 6

encode and transmit genetic information

Question 7

Carbohydrates

Answer 7

provide a source of energy and make up the cell wall in bacteria, plants, and algae

Question 8

Lipids

Answer 8

make up cell membranes, store energy, and act as signaling molecules

Question 9

Polymers

Answer 9

complex molecules made up of repeated simpler units connected by covalent bonds

Question 10

Amino acids

Answer 10

nonessential amino acids synthesized in body

essential amino acids must be obtained

Question 11

Nucleotides

Answer 11

organic molecules that serve as monomers, of DNA, RNA. Building blocks of nucleic acids. Nitrogenous base, 5 carbon sugar, at least 1 phosphate group

Question 12

enyzmes

Answer 12

proteins that function as catalyst which accelerate the rates of chemical rx

Question 13

alpha carbon

Answer 13

central carbon atom

Question 14

carboxyl group

Answer 14

COOH: red

Question 15

Amino group

Answer 15

NH2: blue

Question 16

Ribose

Answer 16

sugar in RNA, has a hydroxyl group on the 2nd carbon

Question 17

deoxyribose

Answer 17

sugar in DNA, has a hydrogen on the 2nd carbon

Question 18

Pyrimidine Base

Answer 18

T, C, U (thymine, cytosine, uracil)

Question 19

Purine Base

Answer 19

A, G (adenine, guanine)

Question 20

DNA bases

Answer 20

A, T, G, C

Question 21

RNA bases

Answer 21

A, U, G, C

Question 22

phosodiester bond

Answer 22

forms when a phosphate group in one nucleotide is covalently joined to the sugar unit in another nucleotide

Question 23

complementary

Answer 23

two bases,
A–T
G–C

Question 24

Carbohydrates

Answer 24

distinctive molecules composed of C,H,O atoms usually in the ratio 1:2:1. Provide a principle source of energy for metabolism

Question 25

Saccharides

Answer 25

simplest carbohydrates, cylic molecules containing 5 or 6 carbon atoms

Question 26

Aldoses

Answer 26

monosaccharides with an aldehyde group

Question 27

Ketoses

Answer 27

monosaccharides with a ketose group

Question 28

glycosidic bonds

Answer 28

the covalent bonds that attach monosaccharides

Question 29

Lipids

Answer 29

hydrophobic, because they share a property and not a structure, they are chemically diverse

Question 30

Triacylglycerol

Answer 30

a lipid used for energy storage, major component of animal fat and vegetable oil.
Made up of 3 fatty acids joined to glycerol

Question 31

Saturated

Answer 31

fatty acids that DO NOT contain double bonds—Said to be saturated because the carbon atoms contain max hydrogen atoms (straight chains)

Question 32

unsaturated

Answer 32

fatty acids that contain carbon-carbon double bonds, have a kink at each double bond

Question 33

steroids

Answer 33

2nd type of lipid, core composed of 20 carbon atoms, bonded to form 4 fused rings, hydrophobic

Question 34

Phospholipids

Answer 34

3rd type of lipid, major component of the cell membrane,. Phospholipids are made up of glycerol attached to two fatty acids and a 3rd molecule containing a phosphate group.. both hydrophilic, and hydrophobic

Question 35

bilayer

Answer 35

a two layered structure with the hydrophilic heads pointing outward toward the aqueous environment and the hydrophovic tails oriented inward, away from the water

Question 36

What percentage of carbon’s orbitals are spherical in conformation?

Answer 36

40%

Question 37

Which one of the following contributes to the measurement referred to as atomic mass?

Answer 37

protons and neutrons

Question 38

If hydrogen bonds between water molecules were weaker than they are today, how would this affect plant height?

Answer 38

As hydrogen bonds are responsible for the movement of water through plant vasculature, plants would be shorter.

Question 39

A woman’s doctor tells her to gargle with salt water. She stirs a tablespoon of salt into a cup of warm water, and watches it dissolve. Why does the salt dissolve in water?

Answer 39

The positive hydrogen atoms in water molecules are attracted to chlorine ions, and the negative oxygen atoms in water molecules are attracted to sodium ions.

Question 40

When two atoms form a covalent bond, they share electrons from all of their orbitals. All of their orbitals, in turn, combine to form a single molecular orbital

Answer 40

false

Question 41

Where would the highest-energy electron be found in an atom of hydrogen?

Answer 41

in the spherical orbital closest to the nucleus

Question 42

Which of the following statements is true regarding atomic mass?

Answer 42

The atomic mass can be used to differentiate between different isotopes of the same element.

Question 43

Water is neither hydrophilic nor hydrophobic, as these terms only define the interaction of other molecules with water molecules

Answer 43

false

Question 44

A polar bond is due to:

Answer 44

uneven sharing of electrons in a covalent bond.