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134 Cards in this Set
- Front
- Back
the definition of matter is?
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any material that takes up space
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what is the definition of energy?
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ability to do work
ex moving matter , heat , light and chemical bonds. |
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what is an element?
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a pure substance that cannot be broken down by chemical means into other substances
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how many natural elements are there?
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92 natural elements
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how many synthetic elements are there?
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25 synthetic elements
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how many elements are essential to life?
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25 elements essential to life
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bulk elements make up what?
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make up majority of living things
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trace elements make up what?
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required in smaller amounts
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what is the periodic table based on?
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based on chemical behavior
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what is an atom?
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smallest “piece” of an element that retains the characteristics of the element
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what is a proton?
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positive charge, nucleus
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what is a neutron?
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neutral charge, nucleus
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what is an electron?
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negative charge, cloud
Very small mass compared to proton or neutron |
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an atom is composed of how many and what kind of particles?
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Atom composed of 3 subatomic particles
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what is the atomic number?
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number of protons in the in the nucleus
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what is a proton?
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positive charge, nucleus
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what is a neutron?
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neutral charge, nucleus
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what is an electron?
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negative charge, cloud
Very small mass compared to proton or neutron |
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an atom is composed of how many and what kind of particles?
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Atom composed of 3 subatomic particles
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what is the atomic number?
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number of protons in the in the nucleus
arranged sequentially |
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the number of protons are equal to?
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the number of electrons.
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an atom is electrically what?
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electrically neutral
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what is an ion?
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atom that has gained or lost electrons
has a net negative or positive charge |
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what is the mass number?
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total number of protons and neutrons in nucleus
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All atoms of an element have the same ______ _______ but not necessarily the same number of _______
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atomic number, neutrons
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what is an isotope?
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different forms of a single element with different numbers of neutrons
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what is atomic mass?
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average mass of all isotopes
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some isotopes are ______ and emit energy when they _____ _____ _____ ______ ______.
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radioactive, break down into stable forms.
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what is a half life?
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time it takes for half of the atoms to decay
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what is a molecule?
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2 or more chemically joined atoms
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what is a Diatomic molecule?
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molecule with 2 atoms of the same element
ex : Oxygen (O2), Nitrogen (N2) |
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what is a compound molecule?
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molecule with 2 or more different elements
ex: Nitric oxide (NO), water (H2O), methane (CH4) |
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what is an orbital
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most likely location for an electron relative to the nucleus, each holds up 2 electrons
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what is an energy shell?
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group of orbitals that share the same energy level
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what is a valence shell?
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outermost occupied energy shell
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how do atoms fill partially empty valence shell?
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atoms will share, steal, or donate electrons
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when is a valence shell full and stable?
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when it is inert
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how many orbitals and electrons are in the first shell?
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one orbital and two electrons.
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how many orbitals and electrons are in the 2nd and 3rd shells?
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4 orbitals each – each holds 8 electrons total
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covalent bonds form when?
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Form when 2 atoms share electrons
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how do the electrons travel in a covalent bond?
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Shared electrons travel around both nuclei
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a single bond has how many electrons?
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1 pair of electrons shared
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a Double bond has how many electrons?
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2 pairs
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a triple bond has how many electrons?
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3 pairs
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what is Electronegativity?
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measure of an atom’s ability to attract electrons
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what is a Nonpolar covalent bond
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equal sharing of electrons
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what is a Polar covalent bond ?
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unequal sharing of electrons
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what is an Ionic Bond?
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Results from the electrical attraction between 2 ions with opposite charges
ex: , forms between an atom with a valence shell almost empty and an atom with a valence shell almost full |
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what are hydrogen bonds?
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Opposite partial charges on adjacent molecules or within the same large molecule attract each other
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what is usually a partially positive member in hydrogen bonds?
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hydrogen
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waters hydrogen bonds.
explain how many, what kind and how. |
2 polar covalent bonds
Oxygen more electronegative and pulls electrons away from hydrogens Partial positive charge on hydrogen attracted to slight negative charge on oxygen in another molecule |
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what is cohesion?
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tendency of water molecules to stick together
based on hydrogen bonding |
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what is adhesion?
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tendency to form hydrogen bonds with other substances
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Cohesion and adhesion both at work in ________ _______
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capillary action
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what is a solvent?
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a chemical in which other substances, solutes, dissolve
ex: water |
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what is a solution?
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1 or more solutes dissolved in a liquid solvent
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what does Hydrophilic
mean? |
Substance readily dissolves in water
Water-loving |
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what does Hydrophobic
mean? |
Substance does not dissolve in water
Polar substances Water-fearing |
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Evaporation
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conversion of a liquid into a vapor
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bodies of water do what more slowly?
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heat and cool
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does water have more or less heat resistance than other liquids?
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More heat is needed to raise water’s temperature than other liquids
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Water has the ability to _____ _________ __________
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Water has the ability to resist temperature changes
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what happens to cells when frozen?
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yes cells are prone to rupture when frozen.
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can some cells have adaptations to prevent damage?
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yeas some make "antifreeze or dehydrate" to prevent damage.
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what are Chemical reactions ?
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when 2 or more molecules “swap” atoms to yield different molecules
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what results from a chemical reaction?
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Products are the resulting material
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what are starting materials called in chemical reactions?
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Starting materials are reactants
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________ _________ break and form new bonds?
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chemical bonds
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What is the pH scale?
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A gauge of how acidic or basic a solution is.
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What is a solution that is less than pH 7?
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Acidic solution
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What is a solution that is more than pH 7?
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Alkaline or basic solution
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What is each unit on the pH scale?
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A 10-fold change in H+ concentration
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What are buffer systems?
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Pairs of weak acids and bases that resist pH changes
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What are organic molecules?
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Compounds that contain both carbon and hydrogen
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What do hydrocarbons consist almost entirely of?
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carbon and hydrogen (CH4)
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What are the 4 types of organic molecules?
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Carbohydrates, lipids, proteins and nucleic acids
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What do linked monomers create?
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Polymers
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Organic molecules are linked using what?
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dehydration which means you take water out of it
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Organic molecules are broken apart by
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hydrolysis which means you add water in
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What are carbohydrates?
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Organic molecules that consist of carbon, hydrogen and oxygen, usually in a 1:2:1 ratio
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What is the significance of simple sugars?
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they are a ready source of energy
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What are monosaccharides?
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5 or 6 carbon atoms
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What are disaccharides?
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2 monosaccharides joined by dehydration synthesis
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What is the formula for sucrose?
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fructose + glucose
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When dealing with monosaccharides, what happens when the same number of carbon atoms are put together differently?
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Very different molecules are formed
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What are oligosaccharides?
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3-100 monomers
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What do the oligosaccharides attach to?
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Proteins on the cell membrane
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What is a polysaccharide?
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Hundreds of monosaccharides together. It is considered a complex carbohydrate.
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What are plant cell walls called?
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Cellulose
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What is the exoskeleton of an insect/cell wall of fungi
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Chitin
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What is starch?
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Plant energy storage
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What is glycogen?
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Animal and fungi energy storage
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Do lipids dissolve in water?
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No they don't dissolve in water.
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What fear do lipids have?
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hydrophobia
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How many groups of lipids are there?
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Several. Three of them are triglycerides, sterols, waxes.
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What is different about lipids from the other 3 major macromolecules?
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They are not polymers made of monomers
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What are triglycerides?
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3 fatty acids bonded to glycerol
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What processes do triglycerides use?
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Dehydration synthesis and hydrolysis
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devastating
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adjective - causing great damage
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Saturated fatty acids have all ________ ________ between carbons.
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Single bonds. EX: Animal fats, solids
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Unsaturated fatty acids have at least 1 ______ _____ between carbons?
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Double bond. EX: plant-derived, liquid
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What are trans fats considered?
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A type of triglyceride
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What is a lipid consisted of?
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4 interconnected carbon rings
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What are 2 examples of lipids?
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Vitamin D, cortisone
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What is used in cell membranes and to make other lipids?
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Cholesterol
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What are waxes?
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Fatty acids combined with either alcohols or other hydrocarbons
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What do waxes form?
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A water-repellent covering
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What is the monomer of a protein?
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An amino acid: central carbon atom bonded to hydrogen, carboxyl group, amino group, and an R group
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The R group distinguishes what?
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Amino acids
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What links amino acids (peptide bond) ?
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Dehydration synthesis
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What breaks amino acids apart?
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Hydrolysis
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What are 4 examples of protein?
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Dipeptide, tripeptide, peptide, polypeptide
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What is the structure of a protein folding?
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A 3D structure
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What is the Primary (1°) structure
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Amino acid sequence determined by organism's genetic code (DNA)
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Secondary (2°) structure
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interactions from coils, sheets, loops
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Tertiary (3°) structure
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overall shape arising from interactions between r groups and water
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Quaternary (4°) structure
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interactions between multiple polypeptide subunits (hemoglobin have 4 subunits)
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What is denaturation?
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loss of structure means loss of function (heat, salt, pH)
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What are the 2 types of nucleic acids?
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Deoxyribonucleic acid (DNA) & Ribonucleic acid (RNA)
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What are the nucleotide monomers?
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5 carbon sugar, phosphate group, and nitrogenous base
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what letters make up DNA?
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a,c,t,g
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what shape is the DNA?
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a double helix
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what holds the DNA together?
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HYDROGEN BONDS HOLD THE HALVES TOGETHER
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which letters of DNA pair with which?
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A with T, C with G
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the genetic code is made up of?
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amino acids
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an amino acid is made of?
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each group of three DNA bases specifies one amino acid
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DNA is made of what sugar?
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Deoxyribose sugar
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RNA is made of what sugar?
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Ribose sugar
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what letters are RNA made of?
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A, C, G and U (not T)
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RNA is made of how many strands?
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Single stranded
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RNA can do three jobs, what are they?
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Enable DNA to be expressed
Function as an enzyme Adenosine triphosphate (ATP) carries energy |
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are there different types of molecules in different organisms?
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same types of molecules in all organisms
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when synthesized in a lab molecules are?
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half left handed and half right handed
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what handed are molecules found in organisms?
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19 of 20 amino acids are left-handed
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