Chapter 3

Question 1

Organic Molecules and Inorganic molecules

Answer 1

organic molecules contain carbon and hydrogen
inorganic molecules do not contain a combination of carbon and hydrogen (H2O and NACL)

Question 2

Hydrocarbon

Answer 2

compound that contains only elements carbon and hydrogen
highly versatile, vary in length and/or have double bonds and/or be branched
ex: methane CH4

Question 3

organic compound

Answer 3

contains carbon

Question 4

The Carbon Atom

Answer 4

total of six electrons
6 protons
almost always shares electrons with elements such as hydrogen, nitrogen, and oxygen
can bond with as many as 4 other elements
often shares electrons with other carbon atoms

Question 5

Isomers

Answer 5

same number and kind of atoms in a variety of arrangements
same molecular formula but different structural formula

Question 6

functional group

Answer 6

specific combination of bonded atoms have similar chemical properties
group of atoms usually found together
hydroxyl group = one of the most common forms (alcohol, sugars)
other common = carboxyl, amino, sulfhydryl, phosphate

Question 7

Four categories of biological molecules

Answer 7

Carbs
Lipids
Proteins
Nucleic Acids

Question 8

Monomers

Answer 8

subunits - single unit

Question 9

Polymer

Answer 9

monomers joined together

Question 10

Dehydration synthesis reaction

Answer 10

joins monomers to form. polymers, equivalent of removing a water molecule
forms larger molecule from smaller molecule
forms a water molecule - byproducts

Question 11

hydrolysis reaction

Answer 11

breaking a chemical bond in presence of water
consumes a water molecule
no byproducts

Question 12

Carbs

Answer 12

Ex: breads, potato, pasta, rice, corn
Glucose: C6H12O6 -> common ex of carb
mainly used for immediate energy source, after there is a crash of fatigue
common ex of hydrolysis reaction - breaking down of maltose to from 2 glucose molecules (maltase involved)
classified as monosaccharides, disaccharides, and polysaccharides

Question 13

Monosaccharides

Answer 13

single sugar molecule, simple sugars
3 to 7 carbon backbone
ex: glucose
- 2 isomers: fructose and galactose
- cells use glucose as the energy of choice
- ribose and deoxyribose as found in RNA and DNA
reducing sugars

Question 14

Disaccharides

Answer 14

2 monosaccharides bonded together
ex: maltose - yeast breaks down maltose in beer for energy and produces ethyl alcohol
sucrose - table sugar

Question 15

Polysaccharides

Answer 15

polymers of monosaccharides
used as energy storage molecules in humans, animals, and plants
ex: starch = plants store
animals store glucose as glycogen
cellulose - plant cell walls - most abundant of all organic molecules
chitin - crab, lobster, insect exoskeletons
non reducing sugars

Question 16

Lipids

Answer 16

insoluble in water
long non polar hydrocarbon chains
relative lack of hydrophilic functional groups
variety of structures and functions
fats and oils used for long term energy storage
ex: cheese, ice cream, lard, butter, oil

Question 17

Fatty Acids

Answer 17

primary component of fats and oils - triglycerides

Question 18

Unsaturated Fats

Answer 18

have double bonds in the carbon chain
typically liquid at room temperature
number of hydrogen less than 2 per carbon atom
trans fat
bent structure ex: canola oil

Question 19

Saturated fats

Answer 19

have no double bonds
linear structure
solid at room temperature

Question 20

Phospholipids

Answer 20

form bulk of plasma membrane, acts as a barrier, supports the cell and protects
polar phosphate head - water soluble
non polar fatty acid - not water soluble
each phospholipid consists of a phosphate head linked to 2 fatty acid chain

Question 21

Steroids

Answer 21

lipids made of 4 fused rings
no fatty acids but are insoluble in water
derived from cholesterol
differ only in functional groups

Question 22

Proteins

Answer 22

Many functions - support, metabolism, transport, defense, regulation, and motion
composed of animo acids monomers
- 20 diff amino acids
- central carbon bonded to hydrogen atom, amino group carboxyl group, and a side chain, or R group
- differ according to R group
Ex: meat, eggs, milk, tofu, beans, nuts, fish/seafood, cottage cheese

Question 23

Peptides

Answer 23

two or more animo acids covalently linked
amino acid sequence determine the final three-shape dimensional shape of protein

Question 24

peptide bond

Answer 24

formed by dehydration reaction between two amino acid monomers

Question 25

polypeptide

Answer 25

chain of many amino acids joined by peptide heads

Question 26

Shape of proteins

Answer 26

function determined by 3d shape
loss of structure and function - denature - usually ue to pH or temp

Question 27

Primary structure

Answer 27

amino acid sequence

Question 28

secondary structure

Answer 28

portions of chains from helices or pleated sheets
holding of polypeptide chain
ex: alpha beta helices

Question 29

tertiary structures

Answer 29

3d arrangements of polypeptide chain

Question 30

quaternary structure

Answer 30

association of several proteins or chains together/interacting

Question 31

nucleic Acids

Answer 31

DNA - stores genetic info
RNA - helps to make proteins
Polymers of nucleotide monomers
- nucleotide composed of a phosphate, 5-carbon sugar, and nitrogen contained base

Question 32

5 type of bases

Answer 32

adenine, guanine, cytosine, thymine (Dna only), uracil (RNA only)

Question 33

DNA

Answer 33

long and packed into compact structure called chromosomes
consists of two twisted polynucleotide strands that forming a double helix
two strands held together by hydrogen bonds between complementary pairs of nitrogenous based (AT, GC)
genetic info stored in sequence of based

Question 34

RNA

Answer 34

ribose as sugar
single stranded
uses Uracil instead of thymine

Question 35

comparing proteins and nucleic acids

Answer 35

sequences of bases in DNA determines sequence of animo acids in proteins
sequence of amino acids determines a protein’s structure and function
small changes in the DNA may cause large changes in a protein - sickle cell amen