(LE1) Chemistry

Question 1

What does the top number represent?

Answer 1

Atomic number: number of protons

Question 2

What does the bottom number represent?

Answer 2

Atomic mass: number of protons + number of neutrons

Question 3

What is an isotope?

Answer 3

Same element with different atomic mass. Different number of neutrons

Question 4

What are valence electrons?

Answer 4

electrons in the outer shell

Question 5

How many electrons are in an uncharged atom?

Answer 5

The amount is equal to the number of protons

Question 6

How is charge determined?

Answer 6

by an unequal number of electrons to protons

Question 7

What are ionic bonds?

Answer 7

donate/accept electrons
- strong bonds

Question 8

What are covalent bonds?

Answer 8

share pairs of electrons
- strongest type of bond

Question 9

What is a Hydrogen bond?

Answer 9

Uneven sharing of electrons results in partial negative in one molecule attracted to partial positive in another molecule
- very weak bond. Electrons aren’t donated/accepted or shared

ex/ H2O molecules

Question 10

What do acids dissociate into? Name an example

Answer 10

Dissociates into H+ and anions
Ex/ HCl -> H+ Cl-

Question 11

What do bases dissociate into? Name an example

Answer 11

Dissociates into OH- (hydroxide) and cations
Ex/ NaOH -> Na+ OH-

Question 12

What do salts dissociate into? Name an example

Answer 12

Cation and anion together. Does not dissociate into H+ or OH-
Ex/ NaCl -> Na+ Cl-

Question 13

What is the relation of the pH scale to [H+]

Answer 13

Inversely proportional to H+ content
Each value is 10x different

Ex/ pH 7 is 100x less acidic than pH 5

Question 14

What are buffers?

Answer 14

prevent large pH fluctuations
ex/ PBS - phosphate buffered saline

Question 15

Name this functional group

Answer 15

Hydroxyl group

Question 16

Name this functional group

Answer 16

Carbonyl group

Question 17

Name this functional group

Answer 17

Carboxyl group

Question 18

Name this functional group

Answer 18

Amino group

Question 19

Name this functional group

Answer 19

Phosphate group

Question 20

Explain what is occurring in this image. What is the specific name? What kind of bond is formed?

Answer 20

Dehydration synthesis to join monomers to make a polymer
- releases a water molecule in the process

This image is specifically Glycosidic linkage
- Glucose + Glucose = Maltose

Covalent bond

Question 21

Explain what is occurring in this image

Answer 21

Hydrolysis to break polymers into monomers
- requires a water molecule in the process

Question 22

Draw an amino acid molecule

Answer 22

Question 23

Draw a glucose molecule

Answer 23

Question 24

What kind of reaction is occurring?

Answer 24

Peptide bond between two amino acids

Question 25

What is the formula for carbohydrate molecules? Write an example

Answer 25

CH2O Ex/ C6H12O6 = Glucose

Question 26

What are monosaccharides? Give examples

Answer 26

Simple sugar 5C Pentose - ribose sugar 6C hexose - glucose

Question 27

What are disaccharides? Give an example

Answer 27

Two monomer sugar (small polymer) ex/ glucose + fructose = sucrose

Question 28

What are polysaccharides? Give examples

Answer 28

Complex sugars (long polymer) Glycogen - glucose Cellulose - glucose

Question 29

What are lipid molecules composed of?

Answer 29

C, H, and O (not CH2O formula) Mostly non-polar

Question 30

What are the three classes of lipids?

Answer 30

Triglycerides - fats Phospholipids - membrane lipids Sterols - cholesterol and steroids

Question 31

What are triglycerides composed of? What are two types of triglycerides?

Answer 31

Glycerol (3C) + 3 fatty acid chains Saturated and Unsaturated fatty acids

Question 32

What is pictured? Describe its characteristics

Answer 32

Saturated fatty acid - no double bonds - straight C-H skeleton - Solid at room temp

Question 33

What is pictured? Describe its characteristics

Answer 33

Unsaturated Fatty Acid - at least one double bond - creates a kinked C-H skeleton - liquid at room temp

Question 34

What kind of bond is used to form triglycerides?

Answer 34

Ester linkage; it is a covalent bond

Question 35

What is the function of cholesterol?

Answer 35

Found in plasma membrane of animals; maintains fluidity of membrane

Question 35

What is shown in the image?

Answer 35

Phospholipid - contains a charged head and uncharged tail - tail is hydrophobic, head is hydrophilic

Question 35

What is the fungi equivalent of cholesterol?

Answer 35

Ergosterol; target for "magic bullet"

Question 36

What are some steroid functions in plants and animals?

Answer 36

Act as hormones ex/ testosterone and estrogen

Question 37

What atoms makeup protein molecules?

Answer 37

C, H, O, N, and sometimes S

Question 38

Name some cellular functions of protein

Answer 38

Enzymes, membrane channels/receptors, structures, hormones, immunity, etc.

Question 39

How many types of amino acids are there?

Answer 39

20

Question 40

What are stereoisomers?

Answer 40

mirror images of amino acids

Question 41

What determines the shape of a protein molecule? What are the different types?

Answer 41

R-group - polar/non-polar - charged/uncharged

Question 42

Describe animal vs bacteria Amino Acids (aa). What is the significance?

Answer 42

They are stereoisomers: L-aa in animals vs D-aa in bacterial cell walls - D-aa can be used as a target for magic bullet

Question 43

What levels of protein structure are there?

Answer 43

Primary, secondary, tertiary, and quaternary

Question 44

What structure level is this? What kind?

Answer 44

Primary Structure: polypeptide chain

Question 45

What kinds of secondary structures are there? What kind of bond is used?

Answer 45

Alpha helix and beta pleated sheets - both hydrogen bonds

Question 46

What are tertiary structures? What determines the structure? What are its functions?

Answer 46

Complex 3-D folds - R-group determines structure - function depends on shape/structure

Question 47

What are quaternary structures? What is an example?

Answer 47

Multiple polypeptides form large multiunit proteins (not found in all proteins) ex/ immunoglobulins

Question 48

What are nucleic acid polymers made of?

Answer 48

Nucleic acid monomers: - phosphate group - Ribose or Deoxyribose sugar - Nitrogenous base

Question 49

What are the different types of nitrogenous base categories?

Answer 49

Purines - 2 rings structure Pyrimidine - 1 ring structure

Question 50

Name different types of purines

Answer 50

Adenine and Guanine

Question 51

Name different types of pyrimidines

Answer 51

Cytosine, Thymine, and Uracil

Question 52

What kind of bond makes up the sugar-phosphate backbone of nucleic acids?

Answer 52

phosphodiester bonds

Question 53

What other bonds are found on a DNA molecule?

Answer 53

Covalent bond between the nucleotides Hydrogen bonds between strands

Question 54

What is the structure of ATP?

Answer 54

same structure as RNA nucleotide, but with three phosphate groups

Question 55

How is ATP creation/release formula written out?

Answer 55