Exam 1 Flashcards
Prokaryotes
unicellular
Eubacteria and Archaebacteria
Eukaryotes
some unicellular, mostly multicellular
Endomembrane System
nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, endoscopes
Cytoplasm
everything between plasma and membrane and nuclear envelope
Cytosol
Gel-like substance excluding the membrane-bound organelles
includes the cytoskeleton and nonmembrane-bound inclusions
Organelles
discrete membrane-bound sub cellular compartments specialized to carry out specific cellular functions
Rough Endoplasmic Reticulum
lots of surface area and membrane, layers of flattened membrance studded with ribosomes for synthesis of protein
Smooth Endoplasmic Reticulum
no ribosomes, smooth tubules, cholesterol biosynthesis, membrane biosynthesis, detoxification
Golgi Apparatus
processes and packages material for secretion out of cell or to different part of the cell
Lysosomes
intracellular digestion…uses enzymes to digest/break down large materials such as fats, proteins, carbohydrates
Central Vacuole
stores water, ions, organic molecules, toxic metabolites
Mitochondrion
oxidation of carbohydrates and fatty acids and production of ATP
has its own ribosomes
Chloroplasts
photosynthesis and starch production
Cytoskeleton
series of proteinaceous filaments and tubules
controls cell shape, cell motility, replication, secretion, gene expression, etc
Microfilaments
Cytoskeleton
made up of strands of the protein actin, often interact with strands of other proteins
Intermediate filaments
Cytoskeleton
made up of fibrous proteins organized into tough, roselike assemblages that stabilize a cell’s structures and help maintain its shape
Microtubules
Cytoskeleton
long, hollow cylinders made u pof many molecules of the protein tubule
matter
anything that takes up space and has mass
compound
contains two or more different elements in a defined ratio
Trace elements
small but important
Fe in Heme
Iodine in Thyroid Hormone
smallest unit of structure containing all of the chemical and physical properties of an element
atom
strong and stable bond resulting from electron sharing
covalent bond
Molecule
two or more atoms held together by covalent bonds
measure of how strongly an atomic nucleus attracts and holds onto electrons
electronegativity
if a covalent bond is formed between two atoms of the same type, the electrons are shared equally
Nonpolar Covalent Bonds
unequal electron sharing
Polar Covalent Bond
Weak Bonds
hydrogen bonds, ionic bonds, van der Waals Interactions
when a Hydrogen covalently bonded to one electronegative atom is attracted to another nearby electronegative atom
weak bonds
Hydrogen bonds
electronegativity difference may be so large as to literally pull electrons from the outer shell
crystal
Ionic Bonds
molecules with nonpolar bonds can have localized regions of partial positive or partial negative charge
determine: 3D shape of proteins, interactions between enzyme and substrate, interactions of antigen-anitbody interactions
van der Waals Interactions
Properties of water
adhesion and cohesion
moderation of temperature (high specific heat)
heat of vaporization
evaporative cooling
solid H2O is less dense than liquid H2O
Plasma Membrane
the membrane found in all cells that separates the interior of the cell from the outside environment
Nucleus
stores DNA/genetic info
Nucleolus
The nucleolus is a spherical structure found in the cell’s nucleus whose primary function is to produce and assemble the cell’s ribosomes. The nucleolus is also where ribosomal RNA genes are transcribed.
What do chemical bonds result from
interactions between valence shell electrons between elements
Four different basic types of molecules
lipids, proteins, carbohydrates, nucleic acids
macromolecules
carbohydrates, proteins, lipids, and nucleic acids form huge molecules
monomer
subunits that make up macromolecules
polymer
chain of covalently attached monomers
dehydration synthesis
removes a water molecule, forming a new bond
one H2O released for every monomer added to the polymer
hydrolysis
one molecule of H2O added for every monomer removed from the polymer
saccharide
sugar
monosaccharide, polysaccharide, etc
monosaccharides have common structure
names that usually end in the suffix -ose
carbohydrates
covalent bond connecting monosaccharides
glycosidic linkage
functions of polysaccharides
energy storage
structure
protection
starch
glycogen
structural polysaccharides
polymers of ß-form monosaccharides
form rigid rods rather than loose helices
cellulose
cellulose
plant cell walls
most abundant organic molecule on Earth
dietary fiber
functions: energy storage, protection, recognition, and structural integrity
carbohydrates
Functions: energy storage, biomembrane structure, hormones
characterized by hydrophobicity
lipids
No C=C
saturated
One C=C
monounsaturated
Many C=C
polyunsaturated
why is water a universal solvent
hydrogen bonding
H2O forms a hydration shell, separating ions allowing them to dissolve in water
increases the relative concentration of h+ in a solution
acid
decreases the relative concentration of H+ in a solution
base
why is carbon structurally loved in organic stuff
4 valence electrons, so it either needs 4 more or 4 less
forms single, double, or triple covalent bonds
hydrocarbons
hydrogens and carbons
nonpolar covalent bonds
relatively unreactive
molecules with the same molecular formulae but with distinct arrangements of the atoms
isomers
specialized form of structural isomer where they differ in the arrangement of groups across a C=C
geometric isomers
cis = same side
trans = opposite side
mirror image isomer molecules that differ in the orientation of atoms around an asymmetric carbon
enantiomers
animal lipids
usually saturated fatty acids
tails pack tightly
solid at room temperature
plant lipids
usually unsaturated fatty acids
tails pack more loosely
liquid at room temperature
oils
phosphlipids
hydrocarbon chains
hydrophobic tail and hydrophilic head = amphipathic
bilayer segregates inside from outside
steroids
4 fused carbon rings
hydrophobic
Protein functions
Catalysts
structure
communication
transport
motility
defense
recognition
regulation
storage
protein monomer
amino acid
amino acid structure
amino group and carboxyl group
different R groups
Polymer formation
amino group and carboxyl group are bonded with a peptide bond
dehydration synthesis –> water is released
four levels of protein structure
primary, secondary, tertiary, quaternary
protein structure that genetically determines linear sequence of amino acids
primary structure
protein structure with hydrogen bonds within the backbone
secondary structure
protein structure with molecular interactions between R groups within the chain
tertiary structure
protein structure with subunit interactions
quaternary structure
Spontaneous protein folding in Isolation
normal protein –> denaturation –> de natured protein –> renaturing (though not always)
factors that impact final protein structure
temperature, ionic strength, pH
correct protein folding
molecular chaperonin…fold molecules in teh right shape
mutation that results from misfolded proteins
sickle cell disease anemia
long, linear chains off covalently bonded nucleotide monomers
Function: storage and transmission of genetic informations
Nucleic Acids
two types of nucleic acids
Ribonucleic Acid (RNA)
Deoxyribonucleic Acid (DNA)
nucleic acid monomer
nucleotide
base + sugar
Purines
Adenine and Guanine
RNA and DNA
Pyrimidines
Cytosine (DNA and RNA)
Thymine (DNA)
Uracil (RNA)
bond that joins nucleotides
phosphodiester bond
Base pairing
A and T
G and C
Metabolism
collection of all biochemical reactions occurring in a cell
breakdown of larger, more complex molecules into smaller, less complex molecules
releases chemical energy
catabolism
synthesis of larger, more complex molecules from smaller, less complex molecules
requires input of energy
anabolism
Energy can be transferred and transformed but it cannot be created or destroyed
1st Law of Thermodynamics
during every transformation, some energy becomes unusable to use –> heat
2nd Law of Thermodynamics
unusable energy
entropy
measure of disorder of the universe
entropy
any process that occurs without input of energy
spontaneous
energy available in a system to do work
free energy (G)
total energy in a system
enthalpy
∆G = ∆H - T∆S
amount of usable energy = total amount of energy - amount of usable energy
spontaneous reaction
free energy is reduced
∆G is negative = exergonic
∆G is negative
exergonic
nonspontaneous reaction
free energy is increased
∆G is positive = endergonic
∆G is postive
endergonic
∆G is 0
equilibrium
is all reactions are at equilibrium…
no free energy change –> no work –> dead cell
anabolic reactions
building large molecules
chemical work
directed movement
ciliary beating, muscle contration, chromosome separation
mechanical work
building gradients
pumping substances across a membrane against a gradient
transport work
generating light
bioluminescence
what forms glycosidic linkage
dehydration synthesis
what are nucleotides made of
nitrogenous base, 5C sugar, phosphate group
What impacts optimal enzyme conditions?
temperature (optimal is 37 degrees C)
pH
Saturation
rate of product formation is at a maximum
all functional enzyme molecules are binding substrate and converting it into product at MAX SPEED
Enzyme effector molecules
Activators and Inhibitors
Increase rate of product formation (in enzyme)
activators
decrease rate of product formation (in enzyme)
inhibitors
nonprotein enzyme activators
Cofactors
organic cofactor = coenzyme
types of enzyme inhibitors
irreversible inhibitors and reversible inhibitors
Covalent attachment to enzyme usually at active site
Irreversible inhibitors
noncovalent attachment to enzyme
reversible enzyme inhibitors
Types of reversible enzyme inhibitors
competitive and noncompetitive
how can the effect of a competitive inhibitor be reduced
by increasing the concentration of substrate
binds to enzyme away from active site
changing structure of enzyme, reducing ability of enzyme to function normally
noncompetitive inhibitor
molecules that bind to an enzyme away from the active site
Allosteric regulatory molecules
molecules that change the conformation and activity of the enzyme
regulatory molecules
Conformations of multisubunit enzymes
functional and nonfunctional
