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Flashcards in Midterm 1 Deck (70):
1

biology is the study of _____

life and living things

2

all living things are made of _____

cells

3

humans get energy from ____

food

4

atom

smallest unit of an element that still has all the chemical properties

5

proton

positively charged subatomic particle

6

neutron

neutrally charged subatomic particle

7

electron

negatively charged subatomic particle

8

covalent bond

-chemical bond
-two atoms share electrons

9

electronegativity

when atoms with different elements form a bond they pull shared electrons towards their nuclei with different strengths

10

ionic bond

electrons are completely transferred from one atom to another (gives one atom full valence shell)

11

anion

negatively charged ion

12

cation

positively charged ion

13

hydrogen bond

attraction between a hydrogen atom with a partial positive charge and another ion with a partial negative charge

14

what important particle is represented by H+

proton

15

potential energy

stored energy

16

kinetic energy

energy of motion

17

thermal energy

kinetic energy of molecule motion relating to heat

18

chemical energy

potential energy stored in chemical bonds

19

what does it mean to say water is a polar molecule?

-water molecules have unequal sharing of electrons
-bc large difference in electronegativity
-hydrogen atoms have partial positive charge
-oxygen atoms have partial negative charge

20

rank the 4 most common atoms in terms of electronegativity

O > N > C = H

21

non polar covalent bonds

-equal sharing
-bond with equally shared electrons
-longest, weakest bonds
-more potential energy
-C-H bonds

22

polar molecules

-unequal sharing
-carry partial positive charge on one side and partial negative charge on other side
-shortest, strongest bonds
-less potential energy
-O-H bonds

23

why is H2O polar, but O2 is not

-H2O has a big difference in electronegativity that causes it to scare electrons unequally: leaving it with partial charges (making it polar)
-O2 as no difference in electronegativity and has equal sharing electrons (making it non polar)

24

what are the 4 ways cells store energy

- bonds (chemical)
- gradients
- excited electrons (short term energy storage)
- reduced molecules (gains e-)

25

spontaneous reactions

proceed on their own without input of external energy

26

non spontaneous reactions

cannot occur on their own without the input of energy

27

reactants

-high potential energy
-more order (lower entropy)
-C612O6 glucose + 6O2

28

products

-low potential energy
-less order (higher entropy)
-6CO2 + 6H2O
-released heat

29

entropy

amount of disorder in a system

30

relationship between H+ and pH

more protons present, more acidic solution becomes/ lower pH

31

how does polarity of water allow it to act as a solvent for charged molecules

-since water is polar, it had partial charges that make hydrogen bonding possible
-H bonds then form with any charged molecule, allowing them to dissolve in water

32

how does water interact with non polar molecules

-water does not interact with non polar molecules
-water in presence of non polar molecules can only bond with itself

33

use the properties of water expansion to explain how the ocean is prevented from freezing

-since water have a very high specific heat it absorbs and releases energy very slowly
-ice less dense than water, any ice that forms floats to the surface insulating the rest of the ocean from the freezing cold

34

use properties of water to explain how water can cool the body

-since water has a high specific heat, it can absorb a lot of heat energy off the body before it evaporates, allowing the body to release heat to cool off

35

miller experiment

miller determined that complex molecules come from simple molecules by interacting in different ways over time

36

polymers

made up of a series of monomers

37

is the formation of polymers from monomers spontaneous or non spontaneous

non spontaneous bc polymers have less entropy than monomers and therefore require more energy to form

38

polypeptides (proteins)

-functions: enzymes, signaling and transport
-made up of amino acids (monomers)
-bond btw monomer: peptide
-formed by condensation

39

polysaccharides (carbohydrates)

-functions: energy storage structure, identifications
-made up of monosaccharides
-monomer bond: glycosidic
-formed by condensation

40

primary structure

-sequence of amino acids in a polypeptide
-DNA: bases are A, T, G, C
-RNA: bases are A, U, G, C

41

secondary structure

-complimentary base pairs
-DNA: double helix
-RNA: hairpin/ fold over on single strand

42

tertiary structure

-3D shapes and compact structures
-bonds of R-groups

43

nucleic acids (DNA, RNA)

-functions: info, storage
-monomer/ made of: nucleotides (A, C, G, T or A, C, G, U)
-monomer bond: phosphodiester
-bond formed by condensation

44

disulfide bond

-connects polypeptide bonds
-forms cystine from thrill group
-results in covalent bond
-strengthens protein structure
-occurs in process of folding of a protein

45

what does it mean for a protein to denature?

-unfolds and can't form properly
-happens when disulfide and H-bonds are broken
-denatured proteins do not function properly

46

heat-shock proteins

-facilitate folding in cells
-recognize denatured proteins and block interactions with other molecules allowing the to refold

47

prion proteins

misfolded forms of proteins that force normal proteins to adopt their infectious misfolded shape

48

diseases associated with prion proteins

-sponge-brain illness (spongiform encephalopathies)
-fatal
-causes degeneration of brain

49

protein activities

-defense
-movement
-signaling
-structure
-transport

50

enzymes

-proteins that catalyze/ speed up a chemical reaction
-act on substrates (reactant molecules)
-allow reacting atoms to interact

51

protein conformation is dynamic

-protein conformation can change
-protein's function dependent on its structure

52

what is antiparallel about double stranded DNA?

-double helix strands of DNA run in opposite directions of each other

53

when is 3D structure formed

-hydrogen bonding
-ionic bonding
-covalent bonding
-van der Waals interactions

54

glycosidic linkage

-condensation reaction
-covalent chemical bond
-link ring-shaped sugar molecules to other molecules

55

hydrolysis reaction that breaks a glycosidic linkage

-H is added to one side and OH is added to the other
-water added/ opposite of condensation reaction

56

alpha glycosidic linkages

-H on top/ OH on bottom of glucose ring
-both molecules face same way to make maltose (condensation)

57

beta glycosidic linkages

-H on bottom/ OH on top of glucose ring
-molecules face opposite ways/ flipped to make lactose

58

what type of bond is easier for animals to digest when carbohydrates are eaten

-alpha
-bc they make glycogen and starch

59

starch

-used for energy storage in plant cells
-store sugars created during photosynthesis
-bonded by alpha

60

glycogen

-used for energy storage in animal cells
-muscle and liver cells to store sugars animals consume
-bonded by alpha

61

cellulose

-used for structural support for cell walls of plants and algae
-bonded by beta

62

chitin

-used for structural support in the cell walls of fungi, external skeletons of insects, & crustaceans
-bonded by beta and hydrogen bonds

63

peptidoglycan

-used for structural support in bacterial cell walls
-bonded by beta and peptide bonds

64

glycoprotein

-protein that has 1 or more carbohydrates covalently bonded to it
-important to cell recognition and signaling
-identifies your cells as YOUR cells

65

C-C and C-H bonds (carbon in reduced state)

-high potential energy
-bc electronegativities are close and electrons are shared equally

66

C-O bonds (carbon in oxidized state)

-low potential energy
-bc oxygen's high electronegativity and unequal sharing of electrons

67

bonds with less potential energy

-polar
-shorter
-not a lot of energy
-unequal sharing

68

bonds with more potential energy

-non polar
-longer
-give more energy
-equal sharing

69

hydrophilic

-polar
-electronegative difference
-interact with water
-soluble
-carbohydrates, some amino acids, nucleic acids

70

hydrophobic

-non polar
-equal electronegativity
-does not interact with water
-insoluble
-lipids, some amino acids