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93 Cards in this Set
- Front
- Back
Define matter |
Anything that takes up space and has mass |
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4 states of matter |
Solid Liquid Gas Plasma |
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All matter, living or non living, is made up of ____ |
Elements |
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Unique properties of elements |
Density Solubility Melting point Chemical reactivity |
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How many NATURALLY occurring elements are there? |
92 |
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Elements that make up 95% of organisms: |
Carbon Hydrogen Nitrogen Oxygen Phosphorus Sulfur |
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What are the 3 subatomic particles atoms are made of? |
Protons Neutrons Electrons |
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What's the atomic mass? |
Protons + neutrons |
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What does the number on top of an element mean? |
Mass # |
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What does the bottom number of an element mean? |
Atomic # |
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Whats the atomic number? |
The number of protons in nucleus |
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The vertical columns on the periodic table are ______ |
Groups |
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The horizontal rows on the periodic table are ____ |
Periods |
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What are isotopes? |
Atoms of the same element with different numbers of neutrons |
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Uses of low level radiation |
Thyroid scan PET scan |
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Uses of high level radiation |
Kill bacteria & fungi Used in food industry Sterilize medical instruments Kill cancer cells |
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What's the octet rule? |
The valence shell is most stable with 8 electrons in it |
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What are molecules? |
When 2 or more of the same or different elements bind together |
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What's the difference between molecules and compounds? |
Nothing |
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When do ions form |
When electrons are transferred from one atom to another |
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Ionic bonding |
The transfer of electrons |
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Covalent bond |
Atoms share electrons so that each atom has an octet in the outer shell |
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What shape are molecules and what does it determine |
3-dimensional; biological function |
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What results if the sharing of electrons is equal? |
Non polar covalent bond |
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What results if the sharing of electrons is unequal? |
Polar covalent bond |
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What is electronegativity |
The attraction of an atom for electrons in a covalent bond |
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Hydrogen bknd |
Polarity in a water molecule causes the hydrogen atoms in one molecule to be attracted to the oxygen in other water molecules |
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How much water are organisms composed of? |
70-90% |
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Is water polar or non polar? |
Polar |
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Why do water molecules cling together? |
Hydrogen bonding |
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Why does water have a high heat capacity? |
The hydrogen bonds that link water molecules help water absorb heat without a great change in temperature |
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Why does water have a high heat of vaporization? |
Heat energy is lost when water evaporates |
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Hydrophilic |
Like/attract water |
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Hydrophobic |
Does not like/attract water |
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Water cohesion |
Water molecules cling together because of hydrogen bonding |
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Adhesion |
Waters positive and negative poles allow it to adhere to polar surfaces |
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Why does water have a high surface tension? |
The stronger the force between molecules in a liquid, the greater the surface tension |
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Ice is (more/less) dense than liquid water |
Less |
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Why does water expand when it freezes? |
Crystal lattice forms with hydrogen bonds farther apart |
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Acids |
Substances that release hydrogen ions when dissociated in water |
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Bases |
Substances that release hydroxide ions and take hydrogen ions when dissociated in water |
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pH below 7 |
Acidic |
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pH above 7 |
Alkaline (basic) |
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What happens when you move down the pH scale from 14-0 |
Each unit has 10x more hydrogen |
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What happens when you move up the pH scale from 0-14 |
Each unit has 10x more hydroxide |
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Buffers |
A chemical or combination of chemicals that keep pH within normal limits |
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A blood pH below 7 |
Acidosis |
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A blood pH above 7.8 |
Alkalosis |
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What do organic chemicals always include? |
Carbon and hydrogen |
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How many electrons in the valence shell of carbon? |
4 |
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Functional grouos |
A specific combination of bonded atoms that always react in the same way |
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Macromolecules |
Contain many smaller molecules joined together |
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Monomers |
Small simple organic molecules that exist individually |
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Polymers |
Large organic molecules formed by combining monomers |
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Examples of monomers |
Amino acids, monosaccharides |
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Examples of polymers |
Proteins, carbs, and nucleic acids |
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Monomers are joined in what kind of reaction? |
Dehydration reaction |
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How are polymers broken apart? |
Hydrolysis reaction |
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Roles of carbohydrates in organisms |
Quick fuel and energy storage |
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What are monosaccharides? |
Sugars with 3-7 carbon atoms |
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What are disaccharides? |
2 monosaccharides joined by the dehydration reaction |
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What are polysaccharides and examples? |
Long polymers that contain many glucose subunits Ex: starch, glycogen, cellulose |
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Glycogen |
Storage form of glucose in animals. Highly branched |
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Starch |
Storage form of glucose in plants. Few branches |
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Where is cellulose found? |
Cell walls of plants |
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What is chitin and where is it found? |
Polysaccharide; crab shells |
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Types of lipids |
Fats & oils for energy Phospholipids from membranes Steroids including sex hormones |
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Fats |
Solid @ room temperature and of animal origin |
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Oils |
Liquid @ room temperature and of plant origin |
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Emulcifiers |
Allow fats to dissolve in water |
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Another name for fat molecules |
Triglyceride |
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Saturated fatty acids |
No double bonds |
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Unsaturated fatty acids |
Have double bonds |
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What is a fatty acid? |
A hydrogen chain that ends with the acidic group -COOH |
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Phospholipids |
2 fatty acids and a phosphate group |
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Which end of a phospholipid is hydrophobic and which is hydrophilic? |
Head is hydrophilic. Tail is hydrophobic. |
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Steroids and examples |
Backbone of 4 fused carbon rings. Ex: cholesterol, testosterone, estrogen |
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What are proteins? |
Polymers composed of amino acid monomers |
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6 functions of proteins |
Structural proteins give support Enzymes to speed up reactions Hormones as chemical messengers Actin & myosin Transport molecules in blood Antibodies to protect cells |
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What are peptides? |
The molecules that make up proteins |
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What is a polypeptide? |
A single chain of amino acids |
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What is a peptide bond? |
Joins 2 amino acids |
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What's a primary structure? |
A linear sequence of amino acids in a straight line |
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What's a secondary structure? |
When the protein takes s certain orientation in space (alpha helix, beta sheet) |
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Tertiary structure |
Multiple alpha helixes or beta sheets |
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Quarternary structure |
Multiple polypeptide chains |
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2 types of nucleic acid |
DNA & RNA |
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What are DNA & RNA polymers of? |
Nucleotides |
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What are the 3 parts of a nucleotide? |
Phosphate Sugar Nitrogen base |
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What are the nitrogen bases of DNA? |
Adenine, thymine, guanine, cytosine |
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What are the nitrogen bases of RNA? |
Adenine, uracil, guanine, cytosine |
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What are the strands of DNA in a helix held together by? |
Hydrogen bonds |
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What is ATP? |
Adenosine triphosphate |