Week 1 (foundations of bio)

Question 1

element

Answer 1

pure substance composed of only one type of atom

Question 2

matter

Answer 2

any substances in the universe that has mass and occupies space

Question 3

isotopes

Answer 3

atoms of an element that posses a different number of neutrons

Question 4

compound

Answer 4

a substance that contains two or more elements

Question 5

molecule

Answer 5

a group of atoms held together in a particular order through covalent bonds

Question 6

ionic bonds

Answer 6

bonds between atoms that gain or lose valence electrons completely

Question 7

covalent bonds

Answer 7

two or more atoms share valance electrons

Question 8

non polar covalent bonds

Answer 8

equal sharing of electrons for a complete valence shell

Question 9

polar covalent bonds

Answer 9

-sharing of electrons is NOT equal -leads to hydrogen bonding
-molecules with polar covalent bonds are hydrophilic (water loving)

Question 10

water cohesion

Answer 10

attraction to other water molecules
(responsible to surface tension)

Question 11

water adhesion

Answer 11

-attraction to other substances
(water is adhesive to any substances with which it can form hydrogen bonds )

Question 12

what does water cling to ?

Answer 12

polar molecules

Question 13

hydrogen bonds

Answer 13

weak attractive forces between hydrogen atoms made partially positive by unequal sharing of electrons

Question 14

hydrocarbons

Answer 14

consist of carbon and hydrogen
-covalent bonds
-not very soluble in water (non polar covalent bonds )

Question 15

functional groups(6)

Answer 15

-all water loving
Carbonyl - C=O
Hydroxyl - OH
Carboxyl - COOH
Sulfidryl - SH
Phosphate - PO
Amino - NH2

Question 16

macromolecules

Answer 16

long molecule built by linking together small, similar subunits

Question 17

dehydration synthesis

Answer 17

removes OH and H during synthesis of a new molecule (removes water)

Question 18

hydrolysis

Answer 18

breaks a covalent bond by adding OH and H (adds water)

Question 19

monosaccharides (simple sugars)

Answer 19

molecules that contain carbon, hydrogen and oxygen
1:2:1 ratio
often form rings

Question 20

diasaccharides

Answer 20

two monosaccharides joined by a covalent (glycosidic) bond

Question 21

polysaccharides

Answer 21

made up of multiple monosaccharides

Question 22

storage polysaccharides

Answer 22

alpha glycosidic bond
-OH pointing down

starch- (plants)
glycogen- (animals)

Question 23

structural polysaccharides

Answer 23

beta glycosidic bond
-OH pointing up

-cellulose (plants
-chitin (insects)

Question 24

3 types of lipids

Answer 24

1) Fats
2) Phospholipids
3) Steroids

Question 25

lipids

Answer 25

molecules insoluble in water

Question 26

what are fats

Answer 26

-consist of a glycerol molecule with 3 attached fatty acids -built by dehydration synthesis

Question 27

saturated fatty acids

Answer 27

in animals straight link (single covalent bonds/ solids)

Question 28

unsaturated fatty acids

Answer 28

in plants double bonds (kinked link/ liquid)

Question 29

phospholipids

Answer 29

form core of membranes composed of -2 fatty acids (hydrophobic) -glycerol -phosphate group (hydrophilic)

Question 30

amphipathic

Answer 30

molecule having both hydrophilic and hydrophobic properties

Question 31

steroids

Answer 31

-maintains integrity of membranes and membrane fluidity -act as hormones

Question 32

polypeptides

Answer 32

amino acids proteins

Question 33

nucleic acids

Answer 33

DNA/RNA nucleotides

Question 34

amino acids

Answer 34

contain an amino group/ carboxyl group and a hydrogen all bonded to a carbon

Question 35

peptide bond

Answer 35

links 2 amino acids

Question 36

polypeptide

Answer 36

when the carboxyl group of a molecule reacts with amino acid group of another molecule releasing water

Question 37

primary level of structure

Answer 37

linear amino acid sequence forms foundation of protein shape

Question 38

secondary level of structure

Answer 38

- alpha helix - beta sheet -hydrogen bonding

Question 39

tertiary structure

Answer 39

3D shape of a single polypeptide molecule

Question 40

quaternary structure

Answer 40

assembly of several polypeptides (protein)

Question 41

chaperones

Answer 41

special proteins that help new proteins fold correctly

Question 42

denaturation

Answer 42

the unfolding of a protein from its active shape - results in loss of function

Question 43

Deoxyribonucleic acid

Answer 43

-encodes info used to assemble - proteins (no oxygen attached ) -double stranded

Question 44

ribonucleic acid

Answer 44

-reads DNA-encoded info to direct protein synthesis (has oxygen attached) -single stranded

Question 45

nucleic acid structure

Answer 45

composed of long polymers, nucleotides -5 carbon sugar -phosphate -nitrogenous base

Question 46

nitrogenous bases and their pairs

Answer 46

purines (A &G) -two rings -adenine and guanine pyrimidines (C,T&U) -one ring -cytosine, thymine and uracil pairs -A/T ( U instead of thymine) -G/C

Question 47

which way do strands run

Answer 47

5’ to 3’ 2 DNA molecules run in opposite directions

Question 48

central dogma

Answer 48

DNA-> RNA-> Protein