Chemisty Flashcards
1
Q
Vertical rows in the periodic table
A
Groups. Elements in the same group have the same reactive properties. Number at the top tells us the number of electrons in the valence shell
2
Q
Horizontal rows in the periodic table
A
Periods/rows. Elements in the same period have the same number of electron shells.
3
Q
What are the four most common elements in the human body?
A
Oxygen (65%)
Carbon (19%)
Hydrogen (10%)
Nitrogen (3%)
4
Q
What eight (non-CHON) elements are also present in the body?
A
Sulphur Sodium Chlorine Calcium Phosphorus Iron Magnesium Potassium (sullen sodden cheese, phobic irate magenta potatoes) SNaP CaKCl FeMg
5
Q
The Octet Rule
A
Atoms really really want to have 8 electrons in their valence shell. Or none at all.
6
Q
How many electrons can the various electron shells hold?
A
First shell: 2
Second shell: 8
Any shell in between #2 and the valence shell: 2-18
Valence Shell: 8 (or 0)
7
Q
Atomic Number
A
The number of protons found in the nucleus of an atom.
Big number on top of elemental name in periodic table
No two elements have the same number of protons
8
Q
Atomic Mass
A
The sum of the protons and neutrons
Measured in Daltons
In periodic table, given underneath name of element
9
Q
Isotope
A
A variation of the same element due to difference in atomic max.
Difference in number of neutrons, since protons never change.
10
Q
What are the isotope forms of Hydrogen?
A
Normal: no neutron
Deuterium: one neutron
Tritium: two neutrons
11
Q
Half-life
A
The time it takes for half of the radioactive atoms in a sample to decay into a more stable form.
12
Q
Free Radicals
A
Atoms/molecules with unpaired electrons in their valence shell.
Highly reactive.
In the body, looking to “steal” electrons from cells (oxidation)
13
Q
Ionic bonds
A
One element donates an electron to the other
Strong normally, but very weak in solution
Tend to form between a metal and non-metal
Ex. NaCl
14
Q
Anion
A
Element that has gained an electron. Negatively charged
15
Q
Cation
A
Element that has lost an electron. Positively charged
16
Q
Ionization
A
The process of gaining or losing an electron
17
Q
Dissociation
A
When ionic bonds break apart in solution. Produces electrolytes.
18
Q
Covalent Bonds
A
When atoms share electrons. Very strong bond, and most common type of bond to occur in the body.
Ex. Methane gas. CH4
Have a tendency for polarity (when one atom has a strong attraction for the shared electrons than the other).
19
Q
Polar Covalent Bond
A
When 2 atoms share the electrons unequally.
Allows greater electro-negativity
Ex. H20. The electron is more attracted to the oxygen, so the H20 molecule is positive on the Hydrogen end and negative on the Oxygen end.
20
Q
Electro-negativity
A
The power to attract electrons to yourself
21
Q
NonPolar Covalent Bonds
A
When 2 atoms share electrons equally.
Ex. CH4 (methane)
22
Q
Hydrogen Bond
A
Weakest of the three bonds
Results from the attraction of opposite parts of molecules, not from electron sharing.
Ex. bonding of water molecules to each other
23
Q
Chemical Reaction
A
The formation of new products due to the breakdown or creation of bonds
24
Q
Potential Energy
A
The energy stored by matter due to its position
25
Kinetic Energy
Energy associated with motion or movement of matter
26
Exergonic reactions
Release energy. A+B => AB + heat
27
Endergonic reactions
Require energy to get started. A+B+heat = AB
28
Activation Energy
The amount of energy required to get a reaction occuring
29
Catalyst
Substances that speed up chemical reactions by reducing the activation energy required.
Remains unchanged at the end of the reaction
30
What are the four types of chemical reaction?
Anabolism
Catabolism
Exchange
Reversible
31
Anabolism
aka Synthesis reaction
A + B -> AB
Tend to be endergonic
Important to growth and healing
32
Catabolism
aka Decomposition reaction
AB -> A + B
Tend to be exergonic
Ex. breakdown of glycogen
33
Exchange Reaction
AB + CD -> AD + BC
Compensates for changes to physiological state and metabolism. If too acidic/basic the body will initiate exchange reactions to create buffers to restore homeostasis.
34
Reversible reactions
A + B AB
35
Inorganic compounds
Don't contain carbon.
| Compose about 60% of the body
36
Intracellular fluid (ICF)
Fluid within the cell (part of cytoplasm)
| Around 2/3 of total body fluids
37
Extracellular fluid (ECF)
Fluid outside cells
Around 1/3 of total body fluids
Itself composed of 80% interstitial fluids and 20% plasma
38
Oxidation-reduction reaction
oxidation: loss of electrons
reduction: gain of electrons
"Oxidation–reduction reactions are always parallel; when one substance is oxidized, another is reduced at the same time. When a food molecule, such as glucose, is oxidized, the energy produced is used by a cell to carry out its vari- ous functions."
(Tortora 38)
39
Plasma
ECF found only in blood vessels
Liquid constituent of blood
Approximately 20% of ECF
40
Solvent
An aqueous component with the ability to dissolve
41
Solutions
Made up of solvent (liquid) and solute (substance being dissolved)
42
Hydrolysis reaction
Water is added to break up the substance
43
Dehydration synthesis reaction
Water removed to create larger substances
44
Hydrophilic
Water loving
Anything polar is hydrophilic!!
Hydrophilic solutes will dissolve easily in water
45
Ion
A particle with either a positive or negative charge
46
Hydrophobic
Water fearing
Solutes that carry non-polar covalent bonds
Will not dissolve easily if at all in water
ex. Fats, oils
47
Heat capacity
The ability to absorb or release high amounts of energy with changes to own temperature.
Water has a very high heat capacity because most of the energy in the form of heat is used to break H bonds, so not much left to raise temperature.
48
Mixture
Combination of physically blended elements and/or compounds that are NOT held together by chemical bonds
49
Colloid
A solution in which the solutes are large enough to scatter light.
50
Suspension
A solution in which the solutes will, over time, separate into their different components
51
Viscosity
The measure of the physical tendency of a liquid to flow.
52
Mole
The measurement of the total number of molecules of a particular substance in a given volume of solution.
Measured in mol/L (aka Avogardro's number: 10 to the 23rd power x molecules)
53
Acid
A substance which dissociates into one or more H+ ion and one or more anions.
Because H+ is a single proton with one positive charge, an acid is referred to as a proton donor.
Because it increases the concentration of H+, the pH is decreased
54
Base
A substance which removes H+ from a solution. Usually dissociates into one or more OH- (hydroxide) ions and one or more cations.
Proton acceptor. Causes pH to increase
55
pH
Percentage of hydrogen. The expression of acidity/alkalinity. Based on the concentration of H+ moles/litre.
```
7 = neutral
7 = base
```
Each number denotes a ten-fold increase in the concentration of H+/litre.
56
Salt
A substance which, when dissociated, releases neither H+ nor OH-, but does release cations and anions.
Results from the reaction of an acid with a base.
57
Buffers
Chemical systems in the body composed of compounds which remove excess H+ and OH- out of solution so the fluids in the body maintain their pH.
Convert strong acids and bases into weak ones.
Prevent acidosis and alkalosis.
58
Carbonic Acid-Bicarboniate Buffer System
If acidic, the bicarbonate ion grabs an excess H+ to create carbonic acid, which is then broken down into water and carbon dioxide.
HCO3 & H+ --> H2CO3 --> H2O & CO2
If basic, carbonic acid breaks down into hydrogen and bicarbonate
H2CO3 --> H+ & HCO3-
59
Phosphate Buffer System
If acidic, monohydrogen phosphate (weak base) grabs H+ and becomes dihydrogen phosphate (weak acid)
H+ & HPO4- --> H2PO4-
If basic, dihydrogen phosphate attaches to an excess hydroxide ion to create water and monohydrogen phosphate.
OH- & H2PO4- --> H2O & HPO4-
60
Protein Buffefrs
Amine group of amino acids act as weak bases and will buffer acids.
Carboxyl group of amino acids will act as weak acids and will buffer bases.
Hemoglobin will also carry away H+
61
Carbon
Atomic #: 6 (therefore 6 protons and 6ish neutrons)
2nd row -- so two electron shells
Group IV -- so 4 electrons in valence shell
About 18.5% of total body mass
62
Four major categories of organics
1) Carbohydrates (CHOs)
2) Lipids (fats)
3) Proteins (made up of amino acids)
4) Nucleic acids (RNA & DNA)
and minor category:
5) ATP (adenosine triphosphate)
63
Organic compounds always contain ______ and are held together by _______ bonds.
carbon
| covalent
64
Hydrocarbons
Carbons bound to hydrogen atoms. Found in carbon skeletons
65
What are the major functional groups in organic chemistry?
1. hydroxyll
2. sulfhydryl
3. carbonyl
4. carboxyl
5. ester
6. phosphate
7. amino
66
Hydroxyl group
Contain OH. Polar and hydrophilic.
R-O-H
Alcohol, the sterols
67
Sulfhydryl group
aka the Thiols
Contain SH group R-S-H
Help form amino acids
68
Carbonyl group
Ketones (breakdown products of fats and proteins) and aldehydes (dehydrogenated alcohols).
Polar and hydrophilic.
CO or CHO
69
Carboxyl group
Contain COOH
Help form amino acids
Can act as acids.
Hydrophilic.
70
Ester group
Found in fats, oils and triglycerides.
Also includes aspirin.
COO
71
Phosphate group.
Contains PO4.
| Key component of ATP
72
Amino group
Contains NH3 (or NH2).
Can act as a base
Contributes to amino acids
73
Monomer
Smallest unit of any organic molecule
74
Polymer
Large organic molecule made of of monomers.
| Usually formed by a dehydration synthesis reaction.
75
Isomer
Molecules with the same chemical formula but different chemical structures, allowing for different reactive properties.
Ex. glucose and fructose
76
Dehydration reaction
Removal of water to form peptide bond
A + B --> AB + H2O
77
Hydrolysis
Addition of water to break peptide bonds
AB + H2O --> A + B
78
Peptide bond
the primary linkage of all protein structures; the chemical bond between the carboxyl groups and amino groups that unites a peptide
A type of covalent bond.
79
Carbohydrates
CHOs
Molecules of carbon saturated with H+ and O2
Mostly end with -ose
3% body mass
80
Three classifications of carbohydrates
1. monosaccharides
2. disaccharides
3. polysaccharides
81
Monosaccharides
```
Simplest carbohydrate. Monomner
Include:
Glucose (in blood)
Fructose (in Fruit)
Galactose (in milk)
Deoxyribose (in DNA)
Riboses (in RNA)
```
82
Galactosemia
a genetic condition in which not enough galactase is produced to break down the galactose. Not the same as lactose intolerance
83
Disaccharide
Product of 2 monosaccharides united via dehydration synthesis
Ex. glucose + fructose --> sucrose + H2O
glucose + galactose --> lactose + H2O
84
Polysaccharide
Tens of thousands of monosaccharides in combination.
Include:
Glycogen (stored energy -- found in muscles and the liver)
Starches (found in plants -- used for pasta and other gustatory goodness)
Cellulose (stored in plants; indigestible)
85
Sources of ATP
Adenosine triphosphate
1) creatine phosphate
2) anaerobic metabolism
3) aerobic metabolism
86
Glycogenolysis
Breakdown of glycogen into glucose
87
Glycolysis
Breakdown of glycogen into pyruvate and indirectly into ATP
88
Glycogenesis
Making glycogen from glucose
89
Gluconeogenesis
Making glucose from fats or proteins.
90
Lipids
Hydrophobic, insoluble (not very polar)
| Only very small lipids or lipids attached to proteins or sugars can dissolve in water.
91
What are the five types of lipids?
1. Fatty acids
2. Triglycerides
3. Phospholipids
4. Steroids
5. Eicosanoids
92
Fatty acids
Simplest fats. Monomers.
Consists of a carboxyl group and a hydrocarbon chain.
Can be catabolized to form ATP
93
Saturated fat
When a fatty acid has only a single covalent bond between the carbon atoms of the hydrocarbon chain
Meats, dairy products, coconut and palm oil.
94
Unsaturated fats
If there is one or more double covalent bonds between carbon atoms of hydrocarbon chain
Creates a kink.
95
Monounsaturated fats
Only one double covalent bond between the fatty acids of the carbon chain.
Olive, peanut, canola and most nut oils.
96
Polyunsaturated fats
Multiple double covalent bonds between the carbon atoms of the hydrocarbon chain. Kinkiest!
Corn, soybean, sunflower and some fish oils.
97
Triglyceride
Composed of one glycerol molecule and three fatty acid chains.
98
Phospholipids
Contains phosphorus
Major component of cellular membranes
Amphipathic (polar head, non polar tails)
When working together to form a membrane, allow non-polar molecules to pass easily (but not polar).
99
Steroids
Consists of 4 rings of carbon
Include sterols: (which also have at least one hydroxyl) group.
Cholesterol (precursor to Vit D and hormones)
Hormones
Bile salt
Vitamin D
100
Eicosanoids
Lipids derived from a 20 carbon fatty acid
Include:
1) prostaglandins (inflammatory response)
2) leukotrienes (allergy and inflammatory)
3) beta carotene (precursor to Vit A)
4) Vit E
5) Vit K
101
What are the six functions of proteins?
1) structural
2) regulatory
3) contractile
4) immunological
5) transport
6) catalytic
102
What are the monomers of proteins?
Amino acids
103
Amino acids
Contain carboxyl group (acid), an amine group (base) and a side chain. COOH-NH2-R
20 altogether (essential and non-essential)
104
Protein synthesis
The creation of proteins by creating peptide bonds between amino acids via dehydration synthesis.
Bond occurs between the N and the C
2 amino acids = dipeptide bond; 3 amino acids = tripeptide bond; lots of amino acids = polypeptide
105
Primary structure of proteins
unique sequence of amino acids in a polypeptide chain.
Genetically determined.
106
Secondary structure of proteins
Repeated twisting of polypeptide chain into either an:
1) alpha helix; or
2) beta sheet
107
Tertiary structure of proteins
The secondary structure folds in upon itself to create a 3-D structure
108
Quaternary structure
Arrangement of 2 or more tertiary structures
109
Denaturing
When a protein is destroyed/altered
110
Enzyme
A protein which acts as a catalyst in biochemical reactions. Reduces activation energy
Composed of an protein portion (apoenzyme) and a nonprotein portion (cofactor)
Enzymes are:
1) Highly specific
2) Efficient
3) Subject to cellular control
111
Nucleic acids
DNA and RNA
Found originally in the nucleus of the cell
Composed of
1) nitrogenous base
- adenine, guanine, cytosine, thymine, uracil
2) pentose sugar (5-carbon sugar)
3) phosphate group PO4
112
DNA
deoxyribose nucleic acid
double helix
Purines: adenine and guanine
Pyrimidines: thymine and cytosine
113
RNA
ribonucleic acid
involved in protein synthesis
single stranded structure
Purines: adenine and guanine
Pyrimidines: URACIL and cytosine
114
Three types of RNA
1. mRNA (messenger) -- transcribes original DNA
2. tRNA (transport) -- involved in amino acid translation
3. rRNA (ribosomal) -- forms template for amino acid translation
115
ATP
Adenine triphosphate
Energy currency of the body
Consists of one adenine, 1 ribose, and a group of phosphates.
ATP + H2O -> ADP + energy + PO4 [uses ATPase]
in reverse, uses ATP-synthase
ADP + energy + PO4 --> ATP + H2O
