Chapter 2: The Chemistry of Life Flashcards
1
Q
What three subatomic particles make up atoms?
A
Protons, neutrons, electrons
2
Q
What do protons give an atom?
A
Its identity
3
Q
What do electrons give to atoms?
A
Its ‘personality’
4
Q
What is a cell?
A
The basic building block of living organisms
5
Q
What is an atom?
A
The basic building block of matter
6
Q
Which particle(s) are in the nucleus?
A
Neutrons, protons
7
Q
Which particle(s) are not in the nucleus?
A
Electrons
8
Q
What is an element?
A
substance that cannot be decomposed into simpler substances by chemical means & has atoms made with identical number of protons
9
Q
Elements are made up of atoms all with the identical number of _____.
A
Protons
10
Q
Atomic number
A
of protons of an atom
11
Q
Atomic Mass
A
Average mass of all atoms of an element
12
Q
Mass number
A
of protons + neutrons
13
Q
Charge
A
Indicates a gain or loss of electrons (ions)
14
Q
How big is 1 proton?
A
1 amu
15
Q
How big is 1 neutron?
A
1 amu
16
Q
How big is 1 electron?
A
nothing (1/1840 the size of a proton or neutron)
17
Q
Isotopes are atoms of the ___ element with a different number of _____.
A
Same, Neutrons
18
Q
Radioactive decay
A
breakdown of the nucleus of an atom
19
Q
What is a radioactive isotope?
A
Isotopes where the nucleus is UNSTABLE and breaks down at a constant rate over time
20
Q
Half-life
A
Constant rate where isotope of the nucleus breaks down. Can be used to figure out ages of elements using graphs.
21
Q
3 ways to use radioactive isotopes
A
- cancer treatment
- tracers (radioactive elements)
- dating rocks/organic remains
22
Q
What is a substance?
A
That which has mass and occupies space; matter.
23
Q
A substance is _____ meaning it is a material with a particular kind.
A
PURE
24
Q
What is a chemical compound?
A
A substance; formed by the chemical combination of two or more elements
25
What is a molecule?
A compound that is bound together by covalent bonds.
26
What is an IONIC compound?
A compound bound that is held together by ionic bonds.
27
What does the octet rule say?
Atoms tend to gain, lose or share electrons so that they have 8 electrons in their outer electron shell.
28
What are valence electrons?
The outermost shell of electrons
29
True or False; Sodium is a pure substance.
True
30
What type of element is sodium? What is its atomic number?
soft metal (alkali metal); atomic number is 11
31
What type of element is chlorine, and what is its atomic number?
pure substance; poisonous gas. its atomic number is 17.
32
Sodium + Chloride = _____
Salt (NaCl), an ionic bond
33
What are ionic bonds?
A bond between atoms when electrons are transferred from one atom to another
34
What are ions?
positive or negatively charged atoms
35
Describe a cation.
loses electrons, creates positive ion
36
Describe an anion.
gains electrons, creates negative ion
37
What are covalent bonds?
Bonds with electrons that are shared by atoms
38
Define single, double, and triple covalent bonds.
Single: Share 2 electrons
Double: 4 electrons
Triple: 6 electrons
39
What is electronegativity?
The want for electrons.
40
Why is a water molecule polar?
There is an uneven distribution of electrons between oxygen and hydrogen atoms.
41
Hydrogen bonds are a type of ____ force.
Van Der Waals.
42
Which is stronger? Hydrogen Bonds vs covalent/ionic bonds
covalent and ionic bonds
43
_____ creates magnet effect.
Polarity of water
44
What is the difference between cohesion and adhesion?
- Cohesion is the attraction between molecules of the SAME substance.
- Adhesion is the attraction between molecules of different substances.
45
Combination of cohesion and adhesion
Capillary action
46
Capillary action is: ____ of ____ to itself and _______ b/w water and ______ causes water to rise in a narrow tube against gravity.
Cohesion, water, adhesion, glass
47
Water drawn out form the roots of a plant to its stems and leaves is an example of? (cohesion, adhesion, capillary action)
CAPILLARY ACTION
48
Water has a (low/high) specific heat capacity. What does this mean?
high. it takes more energy to increase the temperature of water compared to other substances.
49
Specific heat
energy needed to raise temperature of 1 gram of a substance by 1 degree Celcius.
50
Why does water expand as it freezes?
Water is a polar molecule.
51
Mixture
Material composed of 2 or more elements which can be physically separated
52
Solution
Mixture where all components are evenly distributed
53
Suspension
Mixture that contains non-dissolved materials (not evenly distributed)
54
Solute vs solvent
- Solute is the substance dissolved
- Solvent is the substance in which the solute dissolves in
55
What important fluid contains both solutions and suspensions?
Blood
56
Chemical equation for forming water
2 H2 + 1 O2 = 2 H2O
water = hydroxide ion + hydrogen ion
57
what does pH stand for?
Power of Hydrogen
58
What does the pH scale measure?
- the concentration of hydrogen ions (H+) in a solution. 0-14
59
What is the difference between Acids VS Bases?
- Acids have HIGHER concentrations of H+ ions than pure water. pH < 7
- Bases have LOWER concentrations of H+ ions than pure water. pH > 7
60
Buffer
weak acid or base that helps react with strong acids to prevent strong sudden changes in pH. (ex: helping with heartburn)
61
as pH increases by 1, the concentration of H+ ions ______ by a factor of ____.
- decreases
- 10x
62
What are the 4 main types of macromolecules?
- Carbohydrates
- Lipids
- Proteins
- Nucleic Acid
63
Organic chemistry is the study of ____ compounds.
Carbon
64
List 4 ways why it is so important to study the carbon atoms.
- It contains four valence electrons
- Four covalent bonds
- Can bonds with many elements Carbon can bond to sulfur, hydrogen, oxygen, phosphorous, sulfur, and nitrogen.
- Carbon also bonds with other carbon atoms.
65
Macromolecules
"giant molecules" formed from smaller molecules
66
Monomers
Smaller units which are joined together to form polymers
67
Polymerization
Monomers joining together to form polymers
68
Carbohydrate
- Usually in a 1:2:1 ring shape
- Main source of energy
69
Define monosaccharides, disaccharides, and polysaccharides.
Monomer, dimer, polymer.
70
Give 4 examples of monosaccharides.
Fructose, glactose, ribose, deoxyribose
71
Give 3 examples of disaccharides.
Sucrose, Lactose, Maltose
72
What suffix means related to sugar?
-ose
73
Name 4 types of polysaccharides (and expand their definitions)
- Cellulose (plant cell walls)
- Plant Starch (energy source of flour, bread, pasta)
- Chitin (exoskeleton of anthropods)
- Glycogen (animal starch, energy storage)
74
What is the dehydration synthesis?
Removal of water to join MONOMERS together
75
What is hydrolysis?
the "opposite" of dehydration synthesis. ADDITION of water to break POLYMERS apart.
76
What's the chemical process of the dehydration synthesis?
amino acid + amino acid -> peptide + water
77
What are lipids (fats) made of?
Glycerol heads (hydrophillic), Fatty acid tails (hydrophobic)
78
What are two functions of lipids?
- to store energy
- cell membranes
- protection brain/nervous system
- hormones
79
What are two key types of lipids?
triglycerides, phospholipids
80
What is the chemical process of ester bonds?
glycerol + fatty acids -> triglyceride
81
What involves the process of glycosidic bonds?
when SUGARS are joined together
82
What involves the process of peptide bonds?
when AMINO ACIDS are joined together
83
Saturated fat
Full of hydrogen, no double bonds
84
Unsaturated fat
one double bond
85
Polyunsaturated fat
more than one double bond
86
In nucleic acids, what are the monomers?
nucleotides
87
In nucleic acids, what are the polymers?
nucleic acids (DNA/RNA)
88
What is the function of nucleic acids?
they store and transmit hereditary/genetic information.
89
What does each nucleotide contain?
- 5-carbon sugar as ribose or deoxyribose
- phosphate group
- nitrogenous base
90
What sugar does DNA use?
deoxyribose
91
What sugar does RNA use?
Ribose
92
What does ATP stand for?
Adenosine triphosphate (energy carrier)
93
What are the monomers of protein?
Amino acids. There are 20 amino acids, and 9 essential amino acids.
94
What are the polymers of protein?
protein (polypeptides)
95
What is the chemical formula for peptide formulas?
amino acid 1 + amino acid 2 -> water + dipeptide
96
What are the levels of organization of a protein?
- Primary structure - sequence of its amino acids
- Secondary structure - folding or coiling of the polypeptide chain
- tertiary structure - protein starts to wrap and fold around itself, complete 3d arrangement
- quaternary structure - protein starts to fold and wrap around other proteins
97
What is the dehydration synthesis process of a lipid?
glycerol + fatty acids -> triglyceride + 3 water molecules
98
ATP vs ADP
ATP is a "fully charged" battery compared to ADP, which is a partially charged battery.
99
Which molecule contains sugar, a phosphate group, and a nitrogenous base?
(Proteins, lipids, carbohydrates, nucleic acids)
nucleic acids
100
What is likely to be a good energy source for an organism? Carbs/lipids?
carbohydrates; easier to metabolize, more healthier than fat and oil.
101
what suffix means to split or separate?
-lysis
102
Variable
a condition that may cause a change in the system being studied.
103
Controlled experiment
only one experiment is changed to ensure that the effect of only variable can be measured
104
Independent variable
changed by the experimenter during the experiment
105
Dependent variable
What changes as a result of the change in the independent variable
106
Controlled variables
kept constant in each trial as it does not affect the outcome of the experiment
107
Control group
set of organisms or samples that do not receive the treatment (independent variable) that is being tested
108
Isomer
compounds with the same formula but a different arrangement of atoms in the molecule and different properties
109
Is a water molecule neutral or charged? Why?
A water molecule is neutral, because it has 10 protons and 10 electrons.
110
Give an example of cohesion.
water sticking to itself, surface tension
111
Give an example of adhesion.
meniscus of graduated cylinder
112
Give examples for mixtures.
lemonade, salt water, salad dressing
113
Give an example of a solute.
table salt in saltwater
114
Give an example of a solvent.
water in a saltwater solution
115
Suspension example
mud in pond water, paint
116
Solution Example
salt being dissolved in water
117
Identify some real life acids.
lemon, apple, banana, vingear, tomato, milk, hydrochloric acid
118
Identify some real life bases.
baking soda, blood, soap, ammonia, drain cleaner
119
Saturated solution
when a given amount of water has dissolved all of the solute it can
120
CHO
Carbohydrate, lipids
121
CHON
proteins
122
CHONP
Nucleic Acid
123
Exergonic reaction
releases energy, usually occurs spontaneously (ex: cellular respiration)
124
Endergonic reaction
absorbs energy, doesn't occur spontaneously (ex: photosynthesis)
125
Activation energy
energy required to get a chemical reaction started
126
What are catalysts?
A substance that speeds up the rate of a chemical reaction
127
What are enzymes?
Enzymes are proteins that act as a biological catalyst
128
Substrate
The reactant that an enzyme acts on
129
Enzyme-substrate complex
The enzyme binds to its subtrate, forming an enzyme-substrate complex
130
active site
the region on the enzyme where the substrate binds
131
Induced fit
Brings chemical groups of the active site into positions that enhance their ability to catalyze the reaction
132
The active site can lower an E_a barrier by
- orienting substrates
- straining substrate bonds
- providing a favorable microenvironment
- covalently bonding to the substrate
133
What can be used to regulate enzyme activity?
- temperature
- pH
- activators
- inhibitors
134
Denature
Enzyme loses its organized shape and can no longer function, because of drastic changes
135
Competitive inhibition
blocking molecule
136
Noncompetitive inhibition
Allosteric regulation; "on" and "off" keys (binding proteins)
137
Why does ice float on water?
Ice expands while it freezes, and this occurs because of the polarity of water, which occurs from the bent structure of water. This causes the hydrogen bonds to form and open network and make ice less denser than water.
138
What are the monomers of carbohydrates?
Monosaccharides
139
What are the monomers of lipids? What are the polymers?
fatty acids and glycerol heads. Triglycerides and phospholipids.
140
What are the functions of proteins?
- form cellular structures
- control rate of reactions
- regulate cell processes
141
What are the essential elements of PROTEINS (amino acids)?
- Carboxylic acid group
- Amine group
- Variable R side chain
