Chapter 2 Chemistry of life
Electrons
Charged particles that move around an atom's nucleus are A electrons B protons C ions D neutrons
Enzyme
Chemical reactions can be sped up by adding an ______, which lowers the amount of acitivation engery required to start the reaction
Store and transmit hereditary information and gentic info
Describe the functions of the two types of nucleic acids, DNA and RNA
Totally True
The amount of engery needed to cause a chemcial reaction to start is called activation Engery
False
The atomic number of carbon is 6, so it must contain 12 electrons true or false
Atom
The basic unit of matter
C covalent bond
The bond formed when two atoms share a pair of electrons is called A. hydrogen bond B. nopolar bond C Covalent Bond D water bond
Polar Force
The bond that forms between polar molecules that have a positive end and a negative end
Nucleus
The center of an atom
Activation Engery
The energy needed to break existing chemical bonds during the initation of a chemical reaction is called___________
H+ ions in a solution
The ph scale is a measurment system that indicates the concentraion of ________ in a solution
True man this is so true
true or false Because water is a polar molecule, it tends to cause ionic compounds mixed in water to dissociate into ions
Covalent Bond
A bond that forms when electrons are shared between atoms
Ionic Bond
A bond that is formed when electrons are gained or lost by atoms
A reversible reaction
A chemcial reaction that can proceed forward or backward is A reversiable reaction B catalyst C ionic reaction D endergonic reaction
Solution
A combination of two or more substances in which the molecules are evenly distributed and cannot be seprated
Suspension
A mixture of water and non dissolved materials
D. Carbohydrate
A monosaccharide is a A. lipid B protein C Nucleic Acid D carbohydrate E All of the above are true
Electron
A negatively charged particle, that orbits outside the nucleus
Proton
A positively charged particle found in the nucleus
Element
A pure substance that consits of one type of atom
Basic
A solution with a ph of 11 is A. acidic B. Basic C neutral D buffer
b. basic
A solution with a ph of 11 is A. acidic B. Basic C neutral D. Buffer
C. Element
A substance that is composed of only one type of atom is called an A. nucleus B. cell C. Element D molecule
Compound/Bond
A substance that is formed when two elements come together in definite proportions
True
A substance with more of H+ ions than OH- ions is called acidic true or false
C atoms
All matter in the universe is composed of A cells B molecules C. atoms D carbon
A are driven by chemcial reactions
All of the activities occuring within the cells are A driven by chemcial reactions. B. Results from the random mixing of enzymes C. Causes the fluids in the cell to bubble or D results in production of enzymes
A Carbon
All organic compounds contain the element A.(C) B(N) C(Ca) D(Na)
B starch
All the following are lipids except A saturated fat B starch C cholesterol D earwax
Ion
An atom that has gained or lost an electon and now has an electric charge
C ion
An atom that has gained or lost electrons is called A Molecule B nucleon C Ion D element
Cohesion
An attraction between molecules of the same substance
Trues
Atoms in a gas move more rapidly than atoms in a liquid or solid do True or False
Isotope
Atoms of the same element that differ in the number of neutrons they contain
False, False False
Buffers can neutralize acids, but they do not affect bases
C are biological catalysts
Enzymes A. are able to heat up molecules so that they can react B. provide co2 for chemcial reactions C. are biological catalysts D. absorb excess heat so that reactions occur at low temperatures
True yep I it is True
Functional groups are side groups of carbon compounds that confer specific properties to these compounds True or False
D water expands when it freezes
Ice Floats on water because A of cohesion B ice has a higher density than water C. water shrinks when it freezes D. Water expands when it freezes
Electons
If an atom contains 15 protons, it muct contain 15___________
nonpolar molecules
Lipids are A polar molecules B similar to water molecules C protein molecules D nonpolar molecules
C oil
Lipids are soluble in A water B salt water C oil D all the above
B dna and rna
Nucleic Acids include A chlorphyll and retinal B dna and Rna C. lipids and sugars. D glucose and sugars
umm this is true
Organic compounds are substances produced and found in living things True or False
The answer issssss true
The prodcuts of an endergonic chemcial reaction possess more engery than the reactants from which they are produces true or false
Molecule
The structure that results when atoms are joined together by covalent bonds
EELECTRONS
The subatomic particles that makeup atoms are protons, neutrons and ____________________.
Solvent
The substance in which the solute dissolves
Solute
The substance that is being dissolved in a solution
All the Above are true
Water is important to life because it A. surrounds all cells B. is found inside cells. C. influences the shape of the cell membrane D All the above are totally true
All the above
Water molecules break up other polar substances, A. Such as sugars, B because of the uneven charge distribution that exists in water C. thus freeing ions in these substances for use by the body D. all the above
YES I am really true yes true
Without enyzmes, chemcial reactions necessary for life would not occur at a rate sufficient to sustain life True or False
T
Without enzymes, chemcial reactions necessary for life would not occur at a rate sufficient to sustain life
hydroxide, hydrogen
_____ and ____ ions form when water dissociates
water
______is the most common solvent in cells