Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BIOL104 > Week 1 wednesday: Bio-chem > Flashcards

Week 1 wednesday: Bio-chem Flashcards

1
Q

chemicals are the stuff that make up: (3 parts)

A

our bodies, the bodies of other organisms and the physical environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

life’s chemistry is tied to water, what are they? (3 parts)

A

a)life first evolved in water. b)all living organisms require water. c)the chemical reactions of your body occur in cells consisting of 70-95% water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

organisms are composed of elements in combinations called compounds. living organisms are composed of __, which is anything that occupies space and has __ (weight).

A

weight, mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

matter is composed of chemical __.

A

elements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

an __ is a substance that cannot be broken down to other substances.

A

element

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

there are __ elements in nature and only a few exist in a pure state

A

92

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

a __ is a substance consisting of two or more different elements in a fixed ratio.

A

compound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

sodium chloride is a compound of __ + __?

A

equal parts sodium Na and equal parts chlorine Cl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how many elements are essential to life?

A

25

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what 4 elements make up about 90% of the weight of most living organisms?

A

oxygen, carbon, hydrogen, and nitrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are trace elements?

A

common additives to food and water and are only necessary in minute quantities and can prevent disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

without __ your body cannot transport oxygen.

A

iron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

an __ deficiency prevents production of thyroid hormones resulting in goiter.

A

iodine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

__ is added to municipal water and dental products to help reduce tooth decay

A

fluoride

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

several chemicals are added to food to: (3 parts)

A

a)help preserve it. b)make it more nutritious. c)make it look better

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

atoms consist of what 3 things?

A

protons, neutrons, and electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

an __ is the smallest unit of matter that still retains the properties of an element.

A

atom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

protons are __ charged

A

positively charged

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

electrons are __ charged

A

negatively charged

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

neutrons are electrically __

A

neutral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

neutrons and protons are packed into an atom’s __?

A

nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what orbits the nucleus?

A

electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

the negative charge of electrons and the positive charge of protons keep electrons near the __.

A

nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

the number of __ is the atom’s atomic number

A

protons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

an atom’s __ __ is the sum of the number of protons and neutrons in the nucleus

A

mass number

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

the __ __ is approximately equal to its mass number

A

atomic mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

although all atoms of an element have the same atomic number, some differ in __ number

A

mass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

different isotopes of an element have (2 parts)

A

a)the same number of protons. b)but different number of neutrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

different isotopes of an element behave __ in chemical reactions

A

identically

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

in radioactive isotopes, the nucleus decays spontaneously giving off __ and __

A

particles and energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

radioactive isotopes can __ or __ us

A

help or harm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

living cells cannot distinguish between isotopes of the same elements, therefore radioactive compounds in metabolic processes can act as __

A

tracers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

instruments can detect radioactivity, leaving the fate of radioactive tracers can be monitored in __ __

A

living organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

a radioactive imaging instrument that uses position-emission tomography (PET) detects the __ of injected radioactive materials

A

location

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

PET scans are useful for diagnosing __ __ and __

A

heart disorders, cancer, and brain research

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

radioactivity can also be dangerous (2 parts)

A

a)uncontrolled exposure can cause damage to some molecules in a living cell, especially DNA. b)chemical bonds are broken by the emitted energy which causes abnormal bonds to form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

the distribution of __ determines an __ chemical properties

A

electrons, atom’s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

of the 3 subatomic particles -protons, neutrons, electrons - only __ are directly involved in chemical activity

A

electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

electrons occur in energy levels called __ __

A

electron shells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

information about the distribution of electrons can be found?

A

in the periodic table of elements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

an atom may have 1,2, or 3 electron shells surrounding the nucleus. explain this process

A

the # of electrons in the outermost shell determines the chemical properties of the atom. Atoms whose outer shells are not full tend to interact with the other atoms, participating in chemical reactions.

42
Q

atoms with incomplete outer shells tend to react so that both atoms end up with __ __ __

A

completed outer shells

43
Q

these atoms may react with each other by __, __ or __ electrons

A

sharing, donating or receiving electrons

44
Q

these atom reactions usually result by staying together held by attractions called __ __

A

chemical bonds

45
Q

covalent bonds join atoms into __ through electron sharing

A

molecules

46
Q

the strongest kind of chemical bond is a __ __ in which two atoms share one or more outer-shell electrons

A

covalent bond

47
Q

two or more atoms help together by covalent bonds form a __

A

molecule

48
Q

a covalent bond connects two hydrogen atoms in a molecule of the gas __

A

H2

49
Q

there are # different ways to represent common molecules

A

4

50
Q

atoms in a covalent bonded molecule continually compete for shared electrons (2 parts)

A

a)the attraction (pull) for shared electrons is called electronegativity. b)more electronegative atoms pull harder.

51
Q

in molecules of only one element, the pull toward each atom is equal because each atom has the same __

A

electronegativity

52
Q

the bonds formed are called __ covalent bonds

A

nonpolar

53
Q

water has atoms with different electronegativities (5 parts)

A

a)oxygen attracts the shred electrons more strongly than hydrogen. b)so the shared electrons spend more time near oxygen. c)the oxygen atom has a slightly negative charge and the hydrogen atoms have a slightly positive charge. d)the result is a polar covalent bond. e)because of these polr covalent bonds, water is a polar molecule.

54
Q

ionic bonds are attractions between ions of __ charge

A

opposite

55
Q

an __ is an atom or molecule with an electrical charge resulting from gain or loss of electrons

A

ion

56
Q

when an electron is lost a __ charge results

A

positive

57
Q

when an electron is gained a __ charge results

A

negative

58
Q

when the attraction of opposite charges holds the ions together it is called an __ __

A

ionic bond

59
Q

__ is a synonym for an ionic compound

A

salt

60
Q

hydrogen bonds are __ bonds important in the chemistry of life

A

weak

61
Q

most large molecules are held in their three-dimensional functional shape by __
bonds

A

weak

62
Q

hydrogen, as part of a polar covalent bond, has a partial __ charge

A

positive

63
Q

the charged regions on molecules are electrically attracted to __ charged
regions on neighboring molecules

A

oppositely

64
Q

because the positively charged region is always a hydrogen atom, the bond is called a
__ bond

A

hydrogen

65
Q

chemical reactions make and break chemical bonds: (3 parts)

A

a)the structure of atoms and molecules determines the way they behave. b)atoms combine to form molecules. c)hydrogen and oxygen can react to form water

66
Q

the formation of water from hydrogen and oxygen is an example of a __ __

A

chemical reaction

67
Q

the reactants are converted to the __

A

product

68
Q

chemical reactions do not create or destroy matter they only __ it

A

rearrange

69
Q

photosynthesis is a chemical reaction that is essential to life on earth (explain)

A

carbon dioxide (from the air) reacts with water. sunlight powers the conversion to produce the products glucose and oxygen

70
Q

hydrogen bonds make liquid water __

A

cohesive

71
Q

the tendency of molecules of the same kind to stick together is cohesion. (explain)

A

cohesion is much stronger for water than other liquids. most plants depend upon cohesion to help transport water and nutrients from their roots to their leaves.

72
Q

the tendency of 2 kinds of molecules to stick together is __

A

adhesion

73
Q

cohesion is related to __ __ - a measure of how difficult it is to break the surface of a liquid

A

surface tension

74
Q

__ __ give water high surface tension making it behave as if it were coated with an invisible film

A

hydrogen bonds. water striders can stand on water without breaking the surface

75
Q

water’s hydrogen bonds moderate __

A

temperature

76
Q

because of hydrogen bonding, water has a greater ability to resist temperature change than any other liquids. (heat and temperature explain)

A

a)heat is the energy associated with movement of atoms and molecules in matter. b)temperature measures the intensity of heat.

77
Q

heat is __ when hydrogen bonds form

A

released

78
Q

heat must be __ to break hydrogen bonds

A

absorbed

79
Q

when a substance evaporates, the surface of the liquid that remains behind cools down in the process of __ __

A

evaporative cooling. this cooling occurs because the molecules with the greatest energy leave the surface

80
Q

ice is __ dense than liquid water

A

less

81
Q

water can exist as 3 things

A

gas, liquid, solid

82
Q

water is less dense as a solid than a liquid because of __ __

A

hydrogen bonding

83
Q

when water freeze each molecule forms a stable hydrogen bond with its neighbours (2 parts)

A

a)as ice crystals form the molecules are less densely packed than in a liquid water. b)because ice is less dense than water it floats

84
Q

water is the solvent of life. a __ is a liquid consisting of a uniform mixture of 2 or more substances

A

solution

85
Q

the dissolving agent is the __

A

solvent

86
Q

the substance that is dissolved is the __

A

solute

87
Q

an __ solution is one in which water is the solvent

A

aqueous

88
Q

water’s versatility as a solvent results from the __ of its molecules

A

polarity

89
Q

polar or charged solutes __ when water molecules surround them, forming aqueous solutions

A

dissolve

90
Q

__ is an example of a solute that will go into solution in water

A

salt

91
Q

the chemistry of life is sensitive to __ and __ conditions

A

acidic and basic

92
Q

a compound that release H+ to a solution is an __

A

acid

93
Q

a compound that accepts H+ is a __

A

base

94
Q

the pH scale describe how acidic or basic a solution is. the scale ranges from #-# and each pH unit represents a tenfold change in the concentration of H+

A

0-14

95
Q

a __ is a substance that minimizes changes in pH

A

buffer. a buffer accept H+ when it is in excess and it donte H+ when it is depleted

96
Q

acid __ and ocean __ threaten the environment

A

precipitation and acidification

97
Q

when we burn fossil fuels (coal, oil, gas) air polluting compounds and __are released into the atmosphere

A

CO2

98
Q

sulfur ad nitrous oxides react with __ in the air to form acids

A

water. these acids fall to earth as acid precipitation which is rain, snow, fog with a pH lower than 5.2

99
Q

CO2 dissolving in seawater lowers ocean pH in a process known as __

A

ocean acidification

100
Q

the search for extraterrestrial life centres on the search for water. the emergent properties of water support life on earth

A

when astrobiologists search for signs of e.t. life on distant planets they look for water. NASA has found evidence that water was once abundant on mars

BIOL104 (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions