Exam One Reivew
Cell
fundamental unit of life
A(n)_________is an atom that has gained or lost one or more electrons. A(n) ____________attraction is created between a positively charged ____________ and a negatively charged_______________________.
ion ionic cation anion
Molecules that have the same chemical formula (same numbers of each atom) but different three-dimensional shapes are called _____.
isomers
Complexity of order
molecule cell tissue organ organ system organism
Nucleic acids are composed of
nucleotides
the tendency of atoms in stable molecules to have eight electrons in the outermost shells is knowns as
the octet rules
A covalent bond is formed by
the sharing of electron pairs between atoms
Metabolism
the total of all chemical reactions in an organism
Natural selection acts
through differential probabilities of survival and reproductive success
When a protein is denatured, why does it lose its functionality?
Denaturation breaks the weak bonds, such as hydrogen bonds and van der Waals interactions that hold proteins in its three dimensional shape.
In the scientific method, experimental results supported by observations and data of many scientists from many years from
a theory
disulfide bonds
covalent bond formed within a polypeptide between sulfide groups of sulfur-containing amino acids
bicarbonate
body's blood buffer system
The primary structure of proteins is the ______________. The primary structure contains the information necessary to form the secondary structure, including the ______________ and the __________________. The formation of ________________ bonds stabilizes the secondary structure of proteins.
-amino acid sequence - a helix & b pleated sheet -hydrogen
Triglycerides are synthesized from __________ and _______________.
-fatty acids (3) -glycerol
Hydrogen bonding between water molecules cause
-high heat capacity -high surface tension -strong cohesion -strong adhesion properties
lipid hydrocarbon chain
-hydrophobic -nonpolar -good source of storage energy
Examples of hydrogen bonds
-in the DNA between double helix between nucleotides -between water molecules -between a-helices and b-pleated sheets of protein
Starch and glycogens, which are both polysaccharides, differ in that starch is _________________ while, glycogen is _____________
-principle energy sources compound of plants -is a principle energy storage in animals
Proteins
-speed up chemical reactions (enzymes) -functions are dependent on shape -help move things around cell (motor protein) -contain peptide bonds -do not store energy
dehydration synthesis
A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule.
community
All the different populations that live together in an area
The domains of life as prescribed by C. Woese are
Bacteria, Archaea and Eukarya
Hydrolysis
Breaking down complex molecules by the chemical addition of water
Which six elements are the main building blocks of the human body?
C H O P N S
What is the central dogma?
DNA is transcribed into RNA, which is translated into protein
Decomposition ->catabolism Synthesis -> anabolism Exothermic -> release of energy Endothermic -> absorb energy
Decomposition -> releases energy Synthesis -> Absorbs energy Dehydration Synthesis -> anabolism Hydrolysis -> Catabolism
allosteric inhibition
The process in which an enzyme's activity is changed because of binding to the allosteric site.
Phospholipid
a lipid containing a phosphate group in its molecule and two hydrocarbon tail
a solution with a pH less than 7 is called a(n) ___________________and has a higher number of ________________________ than a solution with a pH greater than 7
acid H+
What is the role of van der Waals interactions in biological molecules?
although they are weak bonds, van der Waals interactions help large molecules' three-dimensional shapes and help hold membranes together
phospholipids are
amphipathic
ATP is a high-energy, unstable molecule. A significant amount of energy is found
between the 2nd and 3rd phosphate-to-phosphate bond
A molecule with the formula C₆H₁₂O₆ can be classified as
carbohydrate
Why are cell membranes composed primarily of hydrophobic molecules?
cell membranes can not be soluble in water to separate the aqueous solutions outside of cells from the aqueous solutions inside of cells
Specific heat causes
coastal climates to be more moderate than inland climate
An inhibitor that binds to the active site of an enzyme is a(n) ________________ inhibitor
competitive
Miller and Urey's experiments provided evidence that
complex organic molecules can form spontaneously under conditions that probably existed on the early earth
When electron pairs in a covalent bond spend more time around one atom than the other, this is due to a difference in ________________
electronegativity between the two atoms
Which part of the atoms interact in a chemical reaction?
electrons
The maintenance of a relatively constant internal environment is called
homeostasis
fuctional groups
hydroxyl, carbonyl, carboxyl, amino, sulfhydryl, phosphate, methyl
Enzymes are biological catalysts that function by
lowering the activation energy of the reaction
Unstable isotopes can be useful
medical diagnosis
An inhibitor that binds to a site distinct from the active site a(n) _________ inhibitor
non competitive
proteins consist of amino acids linked by
peptide bonds
Photosynthesis was a significant evolutionary milestone because
photosynthetic organism contributed oxygen to the environment, which led to the evolution of aerobic organisms.
emergent properties
properties or behaviors that emerge only when the parts interact in a wider whole. ex: specific chemical reaction of an enzyme
An element's identity is defined by its
protons
Viruses can not
replicate without a host cell
Oceans provided environments where early organisms thrived because they
shielded organisms from harmful light
A controlled experiment is one that
tests experimental and control groups parallel
Evolution is
the change in the genetic makeup of a population through time