Chemistry of Life (Ch. 2) Flashcards
Anything that has mass and occupies space
Matter
- The amount of material (“stuff”) occupying a space
- The same no matter where you are (even on the moon!)
Mass
The amount of space something takes up
Volume
- The gravitational force pulling on something
- Different depending on where you are (e.g. the moon versus earth)
Weight
- Substance that can’t be broken down into anything simpler (by ordinary chemical means)
- A “pure” substance
- A way of classifying matter
Element
96% of the human body is made up of these four elements (in different combinations)
- Carbon
- Hydrogen
- Oxygen
- Nitrogen
- Smallest piece of an element that has the chemical properties of that element
Atom
The three types of subatomic particles that make up atoms
- Protons
- Neutrons
- Electrons
- Subatomic particles with a positive charge
- Found in the nucleus of an atom
Protons
- Subatomic particles with no charge (neutral)
- Found in the nucleus of an atom
Neutrons
- Subatomic particles with a negative charge
- Orbit outside of the nucleus of an atom
Electrons
- The name for the center of an atom
- Where the protons and neutrons hang out
Nucleus
- Name for the paths electrons take around the outside of an atom’s nucleus
Orbits or shells
The word for the big letter (or two letters) that represents an element on the periodic table or elements
Atomic Symbol
(or Chemical Symbol)
- Unique to each element
- Equal to the number of protons in every atom of that element
- Also equal to the number of electrons every atom of that element starts out with
- The lesser of the two numbers in a box on the periodic table of elements
Atomic Number
- Equal to the (average) number of protons and neutrons added together (for each atom of a specific element)
- The greater of the numbers found in a box on the periodic table of elements
Mass Number (or Atomic Mass Number)
Name the rule:
- Maximum of eight electrons per orbit (shell)
- An atom “wants” eight electrons on an orbit to be “happy”
- This rule does not apply to the FIRST (closest to the nucleus) orbit
- (The first orbit for every atom has a maximum of two electrons)
- 2-8-8-8-… until you run out of electrons
The Octet Rule
For two atoms to form a chemical bond, what has to happen?
(a chemical reaction in which…) their outermost electrons are either TRANSFERRED, or SHARED
What determines what type of chemical reactions (or bonds) an atom will take part in?
The number of electrons leftover on an atom’s outermost shell
Two or more atoms, chemically combined
Molecule
A molecule made up of atoms of two or more different elements
Compound
What do the tiny numbers below each letter in a chemical formula stand for?
- For example: C6H12O6
- Called “subscript”
They stand for how many atoms of each element are in that molecule.
- For example, in C6H12O6:
- 6 atoms of Carbon (C)
- 12 atoms of Hydrogen (H)
- 6 atoms of Oxygen (O)
- = one molecule of the compound glucose
Name the bond:
- Formed by the transfer (giving or recieving) of electrons among atoms
- Results in two oppositely charged ions sticking together, like magnets
- Dissociates easily in water
Ionic bond
An atom with a charge (either positive or negative)
Ion
A positively charged ion
Cation
A negatively charged ion
Anion
Name the bond:
- A bond formed by two or more atoms sharing electrons (to complete each others’ outer shells)
- Represented on paper with dashes:
- Each dash represents an electron being shared between atoms, for example:
- H-H
- O=C=O
Covalent bond
What are the two types of covalent bonds?
- Polar covalent bond
- Nonpolar covalent bond
Name the bond:
- A specific type of covalent bond, where electrons are shared equally between atoms
- Since the shared electron(s) spend an equal amount of time with each atom, both atoms remain neutral (not charged)
Nonpolar covalent bond
Name the bond:
- A specific type of covalent bond, where the electron(s) are unequally shared
- Electrons are more strongly drawn to one atom than the other, so they spend more time hanging out on one the side of the molecule
- The side that the electrons like to hang out at becomes slightly negatively charged (because electrons are negative)
- Molecules made up of these types of bonds dissolve easily in water
Polar covalent bond
Chemical Reactions
If an atom has 1-3 electrons leftover on its outermost shell, it will “want” to:
A) Give away those electrons (Ionic bond)
B) Share electrons (Covalent bond)
C) Recieve electrons from another atom (Ionic bond)
D) Do nothing, its happy the way it is
A) Electron giver*
*Except in the case of hydrogen. Hydrogen only has one electron total, and is a “sharer.”
Chemical Reactions
If an atom has 4 electrons leftover on its outermost shell, it will “want” to:
A) Give away those electrons (Ionic bond)
B) Share electrons (Covalent bond)
C) Recieve electrons from another atom (Ionic bond)
D) Do nothing, its happy the way it is
B) Electron sharer
Chemical Reactions
If an atom has 5-7 electrons leftover on its outermost shell, it will “want” to:
A) Give away those electrons (Ionic bond)
B) Share electrons (Covalent bond)
C) Recieve electrons from another atom (Ionic bond)
D) Do nothing, its happy the way it is
C) Electron receiver
Name the bond:
- Very weak
- Formed between polar molecules, like molecules of water
- The reason water is so special!
Hydrogen bonds
- Refers to combining smaller pieces to make something bigger
- Literally means, “join together”
Synthesis
- Refers to breaking down something into smaller pieces
Decomposition
- A type of chemical reaction where molecules break apart, and trade (or “swap”) pieces of themselves with other molecules.
Exchange reaction
- A specific type of synthesis that occurs in the body
- A water molecule is chemically removed to make room for two molecules to fit together
- An anabolic reaction
- Used for building larger molecules from smaller ones; used for repairing, healing, and growth
Dehydration synthesis
- A specific type of decomposition reaction that occurs in the human body
- A molecule of water is chemically added to break apart a large molecule into two smaller ones
- A catabolic reaction
- Used for digestion
Hydrolysis
The 3 factors that effect the rate (speed) of chemical reactions.
- Concentration
- Temperature
- Catalyst
- The more crowded reactants are, the more likely they are to “bump into” each other
Concentration
- When reactants are heated up, they move around more quickly
- This makes reactants more likely to “bump into” each other
Temperature
- A substance that increases the rate of a chemical reaction
- Does not get altered or used up in the chemical reaction
- For example, an enzyme
Catalyst
- Molecules that contain a carbon “backbone,” or “skeleton” (a chain of carbons covalently bonded to each other)
Organic compounds (organic molecules)
- Molecules that do not contain a carbon “backbone” (or “skeleton”)
Inorganic compounds (inorganic molecules)
- An important inorganic compound; required for chemical reactions in the body
- Helps the body to resist changes in temperature
- Protects the body; lubricates and cushions
- Due to its polarity, many chemicals dissolve readily in it to create mixtures
Water (H2O)
- A mixture made up of a liquid with substance fully dissolved in it
- E.g. saltwater
Solution
- A mixture of a liquid and a non-dissolved substance, which settles out of it if not constantly shaken.
- E.g. oil and vinegar salad dressing
Suspension
- A mixture of a liquid and a non-dissolved substance that does not settle out
- E.g. homogenized milk
Colloid
- A scale that ranks the strength of an acid or base
- Stands for “power of hydrogen”
pH scale
- Any substance that releases H+ (hydrogen ions) in water
- Referred to as a proton donor
- Ranks between below 7 on the pH scale
Acid
- Any substance that binds to H+ (hydrogen ions)
- Referred to as a proton acceptor
- Ranks between above 7 on the pH scale
Base
- Substance with a rank of exactly 7 on the pH scale
- E.g. “pure” water
Neutral
- Inorganic
- Made up of a cation other than H+ and an anion other than OH-
- Created when an acid and a base dissociate in the same water, and participate in an exchange reaction with each other (“partner swap”)
Salt
- An inorganic compound
- You breathe this into your lungs from the air, then it passes into your bloodstream
- Your cells need this to help turn the food you eat into energy they can use
Oxygen (O2)
- An inorganic compound
- A waste product your cells make when they finish breaking down glucose (food) for energy
- You exhale to get rid of it
Carbond dioxide (CO2)
The 4 categories of organic macromolecules
- Carbohydrates
- Lipids
- Proteins
- Nucleic Acids
- An category of organic macromolecules
- Always composed of C, H, and O in a ratio of 1:2:1
- Polar molecules; dissolve in water
Carbohydrates
- A sub-category of carbohydrate
- Called “simple sugars”
- Chain together to form larger carbohydrates
- E.g. glucose (C6H12O6)
Monosaccharide
- A sub-category of carbohydrate
- Made up of two simple sugars (monosaccharides) chemically joined by dehydration synthesis
- E.g. sucrose (table sugar)
Disaccharide
- A sub-category of carbohydrate
- Made up of a chain of many simple sugars (monosaccharides) chemically joined together
- E.g. glycogen, starch, and cellulose
Polysaccharide
- A polysaccharide created in the bodies of animals
- Stores energy
- Found in the liver and skeletal muscles
Glycogen
- A polysaccharide created by plants
- Energy storage for plants
Starch
- A polysaccharide created by plants
- Plants don’t have skeletons, but this allows plants to grow tall
- Found in the cell walls of plant cells; lets them stack like “little bricks”
- Humans can’t digest this, but it is important “roughage” (“fiber”) in our diet
Cellulose
- A category of organic macromolecule
- Composed of C, H, and O (but has much LESS oxygen)
- Nonpolar molecules; insoluble in water (do not dissolve)
Lipids
- A sub-category of lipids
- Energy storage
- Protects organs by “cushioning” them
- Usually occur as triglycerides (1 glycerol + 3 fatty acids)
Fats
- The building block of proteins
- Composed of a central carbon + an amino group + a carboxlic acid group + a lone hydrogen + a variable “R” group
- 20 different variations
Amino Acids
- A chain of covalently bonded amino acids
- Composed of C H O N and sometimes S
Proteins
Name for the covalent bonds between amino acids
Peptide bonds
Changing the shape of a protein by breaking hydrogen bonds
Denature
Sequence of amino acids
Primary Structure of a protein
Two or more proteins functioning together as a unit
Quaternary structure of proteins
- A protein
- A catalyst
- Lowers how much energy is required to kick-start a chemical reaction in the body
- Names end in “-ase”
Enzyme
Substance that an enzyme acts upon
Substrate
- Composed of C H O N and P
- Made up of nucleotides
- Must be made in the body (can’t be used from eaten food)
Nucleic Acids
- Building blocks of nucleic acids
- Made up of a monosaccharide + phosphate group + nitrogenous base
Nucleotides
- Genetic material
- Two strands of nucleotides twisted to form a double helix
DNA (deoxyribonucleic acid)
- A nitrogenous base
- Pairs with thymine in DNA
- Pairs with uracil in RNA
Adenine
- A nitrogenous base
- Pairs with cytosine in both DNA and RNA
Guanine
DNA and globular proteins spun together in a loose thread-like form
Chromatin
Bunched up chromatin ready for cell division
Chromosomes
- DNA double helix “unzips” from the bottom and free floating nucleotides fill in the gaps
- Forms two new DNA molecules but each contain one half (strand) of the original
Semiconservative replication
- A nucleic acid
- Carries out instructions from the DNA
- Synthesizes proteins
- Composed of a single strand
- Has uracil instead of thymine
RNA (ribonucleic acid)
- Composed of adenine + ribose + 3 phosphate groups
- Stores energy from catabolism to provide energy for anabolism
- Called “energy currency”
- The last covalent bond contains *extra* energy
ATP (adenosine triphosphate)
Leftover after removing a phosphate group from ATP
ADP (adenosine diphosphate)
- A glycerol + 2 fatty acids + a phosphate group
- Has a hydrophillic “head” and 2 hydrophobic “tails”
Phospholipid
Water “loving”
Hydrophilic
“Afraid” of water
Hydrophobic
- Derived from fatty acids in response to injury
- Regulate some hormones and blood clotting
- Enhance pain
Prostaglandins
- Lipids whose carbon skeletons are arranged in “C”-shaped rings
- Includes cholesterol and hormones
Steroids
