Chemical Level of Organization Flashcards
1
Q
What is chemistry in regards to human physiology?
A
- the science of structure and interactions of matter
2
Q
What is matter?
A
- anything that has mass and takes up space
- makes up all living things
3
Q
What is mass?
A
- is the amount of matter that makes up an object (does not change)
- not weight
4
Q
What are the four elements that make up 96% of the human body?
A
- oxygen, carbon, hydrogen and nitrogen
5
Q
The human body is composed of how many elements?
A
- 26 different elements
6
Q
How many and which elements make up 3.6% of our body’s composition?
A
- 8
- Calcium, potassium, phosphorus, sulfur, sodium, chlorine, magnesium, and iron
7
Q
How many other elements make up the remaining 0.4% of the body?
A
- 14 (trace elements)
- ex.) zinc, iodine
8
Q
What is an atom?
A
- the smallest units of matter that retain the properties and characteristics of an element
9
Q
What are the contents of an atom?
A
- protons, neutrons, and electrons
10
Q
What is found in the nucleus of an atom?
A
- protons and neutrons
11
Q
Where are electrons found within an atom?
A
- surround the nucleus as a cloud
- very small and light
12
Q
Do neutrons have a charge?
A
- noppppeee.
13
Q
Do neutrons add mass?
A
- Yes
14
Q
Which part of an atom determines the isotope of a certain element?
A
- neutrons
15
Q
Which unit is used to measure atomic mass?
A
- dalton
16
Q
What is the mass of a neutron?
A
- 1.008 daltons
17
Q
What is the mass of a proton?
A
- 1.007 daltons
18
Q
What is the mass of an electron?
A
- 0.0005 dalton
19
Q
What is the atomic number?
A
- number of protons in nucleus
20
Q
What is the mass number?
A
- is the sum of protons and neutrons in an atom and indicates how much the atoms “weighs”
21
Q
What is atomic mass?
A
- atomic weight
- average
22
Q
How are molecules formed?
A
- when atoms share electrons
23
Q
How are molecules represented in writing?
A
- written as a molecular formula showing the number of atoms of each element
24
Q
What is a compound?
A
- a substance that can be broken down into 2 or more different elements
25
What are ions?
- atoms that have given up or gained an electron in their outer electron shell (also called the valence shell)
- uneven number of protons and electrons.
- written with chemical symbol (+) (-)
26
What is a free radical?
- an electrically charged atom or group of atoms with an unpaired electron in its outermost shell
- unstable and highly reactive
27
What are antioxidants?
- substances that inactivate oxygen derived free radicals.
28
What is a chemical bond?
- occur when atoms of a molecule or compound are held together by forces of attraction
- dependent on the number of electrons in outermost shell
29
What are ionic bonds?
- form when an atom loses or gains a valence electron and ions are formed
30
What are cations?
- positively charged ions that have given up one or more electrons (they are electron donors)
31
What are anions?
- negatively charged ions that have picked up one or more electrons that another atom has lost (they are electron acceptors )
32
What is an electrolyte?
- a compound which produces ions when dissolved in a solution such as water
33
What is a covalent bonds?
- formed by the atoms of molecules sharing one, two, or three pairs of their valence electrons.
- can be polar, or non-polar
34
What is the most common type of chemical bond in the body?
- covalent bond
35
Atoms share the electrons equally in which type of covalent bond?
- nonpolar covalent bonds
36
What is the most common type of covalent bond?
- nonpolar covalent bonds
37
What are polar covalent bonds?
- formed by the unequal sharing of electrons between atoms
38
Why are polar covalent bonds extremely important?
- all-important water molecule makes use of this bond
39
What are hydrogen bonds?
- are weak interactions (approximately 5% as strong as covalent bonds) between hydrogen and adjacent electronegative atoms like oxygen or sulfur.
- CANNOT bind atoms into molecules.
40
When do chemical reactions occur?
- when new bonds form and/or old bonds are broken
41
What is Metabolism?
- the sum of all the chemicals reactions in the body
42
What are reactants?
- the materials that are present at the start of the chemical reaction
43
What are products?
- the substances are the end of the chemical reaction
44
What is the law of conservation of energy?
- the total mass of reactants equals the total mass of the product.
45
What is kinetic energy?
- the energy of matter in motion
46
What is chemical energy?
- energy is stored in chemical bonds
47
What is potential energy?
- energy stored by matter due to an objects position
48
What is an exergonic reaction?
- releases more energy than they absorb (heat during catabolism of food) by breaking a bond with Moe energy than the one being formed
49
What is an endergonic reaction?
- require that energy be added, usually from a molecule called, to form a bond.
50
What is activation energy?
- the energy required to break chemical bonds in the reactant molecules so a reaction can start
51
What are some factors that cause a collision (and chemical reaction to take place) ?
- temperature, concentration of reactants, the presence or absence of a catalyst
52
What are catalysts?
- chemical compounds that speed up chemical reactions by lowering the activation energy needed for a reaction to occur
- not consumed or produced
- used over and over again
53
What does a catalyst do in a chemical reaction?
- helps properly orient the colliding particles of matter so that a reaction can occur at a lower collision speed
- does not alter the difference in potential energy between reactants and products
- only lowers amount of energy needed to start reaction
54
What increases the chance of a collision occurring?
- an increase in temperature and concentration
55
How is concentration increased?
- by adding more particles present or increasing pressure
56
What happens when temperature is increased in a reaction?
- the speed of moving particles increases, thus increasing collision likelihood and time
57
What is a synthesis reaction? (anabolic)
A + B => AB
| - occurs when two different atoms or molecules interact to form a different molecule or compound.
58
What is a decomposition (degradation) reaction? (catabolism)
AB => A + B
| - processes in which chemical species break up into simpler parts
59
What is an exchange reaction?
AB + CD => AD + CB
| - only difference between the reactants and the products is in the iso topically substituted species
60
What are reversible reactions?
AC <=> A + C
| - products can be changed back into the original reactants
61
What are oxidation-reduction reactions?
- essential to life
- breaks down food molecules to produce energy
- reactions are concerned with the transfer of electrons
- always parallel - when one substance is oxidized, another is reduced at the same time
62
What is oxidation?
- loss of electrons and in the process, the oxidized substance releases energy
63
What is reduction?
- gain of electrons and in the process, the reduced substance gains energy
64
What is an inorganic compound?
- any substance in which two or more chemical elements (usually lack carbon) are combined
65
What is an organic compound?
- always contains carbon
- large, complex molecules
- usually contain hydrogen
- always have covalent bonds
66
What is the most important and abundant inorganic compound in all living systems?
- Water
67
Do the bodies chemical reactions occur in a watery medium?
- yes, majority
68
What is waters most important property?
- polarity
| - uneven sharing of valence electrons that enables reactants to collide to form products.
69
Is water usually a solvent or a solute?
- solvent
| - essential for health and survival
70
In a solution the ... dissolves the ...
- the solvent dissolves the solute
71
Is there usually more solvent or solute present?
- more solvent than solute
72
Substances which contain polar covalent bonds and dissolve in water are...?
- hydrophilic
73
Substances which contain non-polar covalent bonds are...?
- hydrophobic
74
What are the properties of water that allow it to interact with several neighbouring ions or molecules?
- polarity
| - bent shape
75
What are the properties of a solute that is hydrophilic?
- charged or contain polar covalent bonds
76
What are the properties of a solute that is hydrophobic?
- molecules that contain mostly nonpolar bonds
77
When does a dehydration synthesis reaction occur?
- when two small molecules combine to form 1 large molecule and a water molecule
78
What is hydrolysis?
- to loosen or break apart molecules with the addition of water
79
What substance in the human body often acts as a lubricant?
- water
80
Why is waters high heat capacity important?
- it can absorb or release a relatively large amount of heat with only a modest change in its own temperature
- caused by large number of hydrogen ions
81
What is the absorbed heat energy in water used for in chemical reactions?
- Break the hydrogen bonds resulting in less energy used to speed up water molecules
82
What is the heat of vaporization?
- amount of heat needed to change from liquid to a gas
83
What is a mixture?
- A combination of elements or compounds that are physically blended together but are not bound by chemical bonds
84
Does water in the body increase or decrease with age?
- decreases
85
What is a colloid mixture?
- large particles than a solution.
- particles are large enough to scatter light
- ex.) milk
86
What is a suspension mixture?
- suspended material may mix with the liquid or suspending medium for sometime, but it will eventually settle out
- ex.) blood
87
How can you explain the amount of a molecule in a solution?
- concentration
88
How is relative mass presented in a solution?
- percentage
| - usually in grams
89
What is a mole?
- a convenient way of counting large numbers of atoms or molecules
90
What is 1 mole? (numerical representation)
6.02 x 10^23
91
How much does one mole of hydrogen atoms weigh?
1.01 grams
92
How much does one mole of oxygen atoms weigh?
- 15.999 grams
93
How much does one mole of sodium atoms weigh?
- 22.989 grams
94
How can one determine the weight of 1 mole of any atom or molecule?
- atomic mass of an element
| - molecular mass of the compound
95
Explain the acids and bases scale.
- runs from 0-14
- pH = -log[H+]
- logarithmic, not linear
96
The lower the number of pH, the ……. the H+ concentration.
- higher
97
A change of two pH units represents how much of a change in hydrogen concentration?
- hundred times concentration
98
A change of three pH units represents how much of a change in hydrogen concentration?
- 1000 times concentration
99
What is the pH of an acid?
- pH < 7
- ([H+] > [OH-])
- proton donor
100
What is the pH of a base?
- pH > 7
- ([H+] < [OH-])
- proton acceptor
101
What is a buffer system in the body?
- A chemical system that prevents a radical change in fluid pH by dampening the change in hydrogen ion concentrations
- usually a weak acid or a weak base
102
What is the major buffer system in the body called?
- Carbonic acid bicarbonate
103
What is the pH of blood?
- 7.35-7.45
104
What are functional groups?
- certain molecular configurations which are easy to recognize
- a characteristic reactive unit of a chemical compound especially in organic chemistry
105
What are some common functional groups?
- Ester, amino groups, carboxyl (acid) groups and phosphate groups
106
What are polymers/ macromolecules?
- molecular structure consisting chiefly or entirely of a large number of similar units bonded together
107
What is an isomer?
- two or more compounds with the same formula but a different arrangement of atoms in the molecule and different properties
108
What provides most of the chemical energy needed for life?
- carbohydrates
| - sugars, starches, glycogen, and cellulose
109
What are carbohydrates made of?
- carbon, oxygen, hydrogen
| - 2:1 ratio of hydrogen to oxygen
110
What are the three major groups of carbohydrates?
- monosaccharides
- disaccharides
- polysaccharides
111
What are the simplest forms of sugar called?
- monosaccharides
| - glucose, fructose, galactose
112
Where are 5-carbon sugars used?
- nucleic acids
113
How are disaccharides made?
- combining 2 monosaccharides by removing a water molecule
| - dehydration synthesis
114
What are some examples of a disaccharide?
- sucrose
| - lactose
115
What is sucrose made of?
- glucose and fructose
116
What is lactose made of?
- glucose and galactose
117
What are polysaccharides?
- contain hundreds of monosaccharides
118
What is the most common polysaccharide found in the human body?
- glycogen
119
Why are lipids hydrophobic and mostly insoluble in water?
- they lack polar covalent bonds
| - have nonpolar covalent bonds.
120
How do lipids become water soluble?
- combine with proteins for transport in blood
121
What are some types of lipids in the body?
- fatty acids
- triglycerides
- phospholipids
- steroids
- eicosanoids
122
What are lipids made of?
- contain carbon, hydrogen, and oxygen
123
What is the simplest form of lipids?
- fatty acids
124
What is the building blocks for triglycerides and phospholipids?
- fatty acids
125
What are fatty acids made of?
- a carboxyl group and a hydrocarbon chain
126
What type of bonds are found in saturated fatty acids?
- single covalent bonds between carbon atoms and as a result each C is saturated with H atoms.
127
What type of bonds are found in unsaturated fatty acids?
- contain 1 (monounsaturated) or more (polyunsaturated) double covalent bonds between C atoms.
- Thus the C are not completely saturated with H atoms.
128
What are the most plentiful lipids in the body?
- triglycerides
129
What is the job of triglycerides in the body?
- protection, insulation, and energy
130
What are triglycerides made of?
- 1 glycerol attached to three fatty acids chains
131
How are triglycerides produced?
- through dehydration synthesis
| - can be reduced through hydrolysis
132
What form of matter are triglycerides at room temperature (saturated)?
- solid
133
What form of matter are triglycerides at room temperature (unsaturated)?
- liquid (oils)
134
Are oils monounsaturated or polyunsaturated?
- oils contain fatty acids that can be both
135
Is triglyceride storage limited or unlimited?
- unlimited
136
What is the most concentrated form of chemical energy?
- fats (triglycerides)
137
How many calories are in a gram of fat?
- 9 g
138
What happens to excess dietary carbohydrates, proteins, fats, and oils?
- deposited in adipose tissue as triglycerides
139
Why are phospholipids important?
- important membrane components for cells
140
What makes phospholipids soluble in both water and fats?
- Polar and nonpolar regions
- amphipathic
- both hydrophilic and lipophilic
141
Is the head of a phospholipid polar or non-polar?
- polar
142
What is the structure of a phospholipid?
- polar head from phosphate group
- glycerol molecule (hydrogen bonds w water)
- to non-polar fatty acid tails
143
What do the two nonpolar fatty acid tails interact with?
- only lipids
144
How many rings of carbon atoms do steroids have?
- 4 rings
145
What are some types of steroids?
- sex hormones, bile salts, some vitamins, cholesterol, cortisol
146
Why is cholesterol and important component of cells?
- component of the membrane
| - starting material for synthesizing other steroids
147
Which elements are found in proteins?
- carbon, hydrogen, oxygen, and nitrogen
148
Which macromolecule is considered the most human of all organic compounds?
- protein
149
What are the functions of proteins?
- structural, regulatory, contractile, immunological, transport, catalyst
150
How are proteins constructed?
- different combinations of amino acids
151
What are amino acids?
- The monomers of proteins
152
How many amino acids are there?
- 500 in nature
153
How many amino acids are found in the body?
- 20
154
Which structural area of amino acids varies?
- the “R” group
155
What are dipeptides?
- formed from two amino acids joined by covalent bonds (peptide bonds)
156
What are peptide bonds?
- when the carboxyl group one molecule reacts with the amino group of another molecule, releasing a molecule of water
- dehydration synthesis
157
What are polypeptide chains?
- chains that contain 10 to 2000 amino acids
158
How many levels are there to which proteins are structurally organized?
- 4
159
What is a primary level proteins?
- gives a unique sequence of amino acids and there’s genetically determined
160
What is the secondary level of proteins?
- The repeated twisting and holding of primary sequence
161
What are tertiary proteins?
- to three-dimensional shape, folding of secondary level proteins
162
What is a quaternary protein?
- arrangement of individual polypeptide chains and proteins containing more than one polypeptide
163
Why is the shape of a protein important?
- resulting shape of protein greatly influences its ability to recognize and bind to other molecules
164
What is denaturation?
- The loss of a protein structure caused by a hostile environment
- causes loss of its characteristic shape and function
165
What causes denaturation?
- A change in pH or high temperatures
166
What are enzymes?
- special proteins at catalyze metabolic reactions in all living cells
- speed up process
167
What is the substance of an enzyme?
- The substance upon which an enzyme has its affect
168
How do enzyme speed up chemical reactions?
- they increase the frequency of collisions, lowering activation energy, improperly orienting colliding molecules
169
What are the two parts of enzymes?
- apoenzyme (protein part)
| - cofactor (non-protein)
170
Are cofactor parts of enzymes inorganic or organic?
- they can be both!
- inorganic = metal ion
- organic = usually derived from vitamins
171
What are three important properties of enzymes?
1. Enzymes are highly specific
2. Enzymes are highly efficient
3. Enzymes are subject to a variety of cellular controls
172
What are nucleic acids?
- huge organic molecules composed of monomeric nucleotides
| - contain carbon hydrogen oxygen nitrogen DNA and RNA
173
What type of information do nucleic acids carry?
- deoxyribonucleic acid and ribonucleic acid
| - genetic information
174
Where are DNA molecules found?
- inside the nucleus of cells
175
What is the function of DNA?
- they are the master template of our genetic code
176
What is the function of RNA?
- relays instructions from the nucleus to guide assembly of amino acids into proteins in the cytoplasm
177
What are nucleotides of DNA composed of?
- A nitrogenous base
- A pentose sugar
- A phosphate group
178
What is considered the backbone in the nucleotides of DNA and RNA?
- sugar phosphate
179
Explain the formation of DNA (double helix structure).
- two sugar phosphate strands of DNA, joint in the middle by hydrogen bonds from one nucleotide to another
180
Is RNA single-stranded or double-stranded?
- single-stranded
181
Explain the structure of RNA.
- ribose replaces the sugar deoxyribose and uracil is the nitrogenous base that replaces thymine
182
What are the three types of RNA within a cell?
1. Messenger RNA
2. Ribosomal RNA
3. Transfer RNA
183
What is ATP used for?
- Temporary storage of energy that is being transferred from exergonic catabolic reactions to cellular activities
184
What is a common nickname used for ATP?
- molecular unit of currency
185
Synthesis of ATP is catalyzed by what?
- ATP synthase enzyme
186
How is ATP broken down to be used for energy?
- High energy phosphate is hydrolyzed by the enzyme ATPase to release the stored energy - leaving ADP
187
How much ATP will human use in a day?
- up to their own body weight
188
How many time does each ATP molecule get recycled during a single day?
- 1500 times
189
What are the two phases of cellular respiration?
- anaerobic phase
| - aerobic phase
190
Explain the anaerobic phase of cellular respiration.
- reactions do not require oxygen where glucose is partially broken down into pyruvic acid
191
What is the purpose of pyruvic acid in the anaerobic phase of cellular respiration?
- Pyruvic acid yields two molecules of ATP
192
Explain the aerobic phase of cellular respiration.
- reactions in the presence of oxygen where glucose is broken down into carbon dioxide and water
- generation of heat and 30 or 32 ATP molecules
