BIO 111 Ch. 1-7
methyl
-CH3
carboxyl
-COOH; acts as an acid
amino
-NH2; acts as a base
hydroxyl
-OH; alcohol
phosphate
-OPO3 (2-)
sulfyhydryl
-SH; can react, forming a "cross-link" that helps stabilize protein structure
proteins
1+ polypeptides folded and coiled into a specific 3D structure
carbonyl
> C = O; ketoses; ketone and aldehyde
ocean acidification
CO2 dissolved in sea water forms carbonic acid; decreases pH
How does diversity relate to evolution?
Diversity refers to the variation of life forms in different ecosystems. Evolution creates the diversity of life on Earth.
solution
a liquid that is a completely homogeneous mixture of substances
cellulose
a major component of the tough wall of plant cells; polymer of glucose
lysosome
a membranous sac of hydrolytic enzymes that can digest macromolecules
DNA (Deoxyribonucleic acid)
a nucleic acid made of nucleotides with chromosomes containing genetic material; controls the development and maintenance of organisms
hydrolysis
a reaction that is essentially the reverse of the dehydration reaction; a water molecule is gained, and a bond is broken
plasma membrane
a selective barrier that allows sufficient passage of oxygen, nutrients, and waste to service the volume of every cell; made of proteins and phospholipids
molecular formula
a shorter abbreviation (i.e. H2)
starch
a storage polysaccharide of plants; made up of glucose monomers; simplest form of starch is amylose
compound
a substance consisting of 2+ elements in a fixed ratio
element
a substance that cannot be broken down to any other substances by chemical reactions
tonicity
ability of a surrounding solution to cause a cell to gain or lose water
proton pump
actively transport hydrogen ions out of a cell against their concentration gradient; main electrogenic pump of plants, fungi, and bacteria
sodium-potassium pump
actively transport sodium out and potassium in; major electrogenic pump of animal cells
base pairing
adenine/thymine, guanine/cytosine, uracil/adenine
hydrophobic
afraid of water
transport proteins
allow the passage of hydrophilic substances across the membrane; is specific for the substance it moves
cell wall
an extracellular structure that distinguishes plant cells, fungi, prokaryotes, and some unicellular eukaroyotes from animal cells
acid
any substance that increases the H+ concentration of a solution; pH < 7
base
any substance that reduces the H+ concentration of a solution; pH > 7
matter
anything that takes up space and has mass
evaporative cooling
as a liquid evaporates, its remaining surface cool
3 domains
bacteria, archaea, and eukarya
carrier proteins
bind to molecules and change shape to shuttle them across the membrane; undergo a subtle change in shape that translocate the solute-binding site across the membrane
organization of biology (largest to smallest)
biosphere, ecosystem, community, population, organisms, organs, tissues, cells, organelles, molecules
nucleic acids
blueprint for proteins and through the actions, for cellular activities
peripheral proteins
bound to the surface of the membrane
taxonomy
branch of biology that names and classifies species into groups
peroxisome
break down hydrogen peroxide by converting it to water
6 major functions of transmembrane proteins
can transport, enzymatic activity, signal transduction, cell-cell recognition, intercellular joining, and attachment to the cytoskeleton and extracellular matrix
What are the 4 classes of large biological molecules?
carbohydrates, lipids, proteins, nucleic acids
ribosome
carry out protein synthesis in the cytosol (free ribosomes) and on the outside of the endoplasmic reticulum (ER) or the nuclear envelope (bound ribosomes)
isotonic
causes no net movement of water into or out of the cell
hypotonic
cell gains water
pinocytosis
cell ingests extracellular fluid and its dissolved solutes
hypertonic
cell loses water
endocytosis
cell takes in macromolecules by forming vesicles from the plasma membrane
plasmodesmata
channels between adjacent plant cells; water and small solutes (and sometimes RNA and proteins) can pass from cell to cell
eukaryotic cell
characterized by having DNA in a nucleus that is bounded by a membranous nuclear envelope, membrane-bound organelles, and cytoplasm in the region between the plasma membrane and nucleus; much larger than prokaryotic cells
ionic bond
chemical bond resulting from the attraction between oppositely charged ions
essential elements
chemical element required for an organism to survive, grow, and reproduce; carbon, hydrogen, oxygen, and nitrogen
adhesion
clinging of 1 substance to another; H2O to plant cell walls
golgi apparatus
consisting of stacks of flat membranous sacs that modify, store, and route products of the ER; manufactures certain macromolecules; sorts and packages materials into transport vesicles
hydrocarbon
consists only of hydrogen and carbon
fats
constructed from 2 types of smaller molecules (glycerol and fatty acid)
nucleus
contains most of the cell's genes and usually the most visible of organelles
hormonal proteins
coordination of an organism's activities
plasmolyzed
cytoplasm shrivels and plasma membrane pulls away from cell wall; when cell loses water to a hypertonic environment
radioactive isotopes
decay spontaneously; unstable
tertiary structure
determined by interactions among various side chains; overall shape of a polypeptide
osmosis
diffusion of water across a selectively permeable membrane
passive transport
doesn't require ATP
taxonomic classification of organisms (largest to smallest)
domain, kingdom, phylum, class, order, family, genus, species
inductive reasoning
draw conclusions through repeating specific observations; lead to important generalizations
nucleotide
each polynucleotide is made up of monomers; consists of a nitrogenous base, a pentose sugar, and 1+ phosphate groups
scanning electron microscope (SEM)
electron beam scans the surface of the specimen and shows topography; 3D images; uses electromagnets
valence electrons
electron in the outermost shell
electron shell
electron's state of potential energy
trace elements
element indispensable for life but required in extremely small doses
kinetic energy
energy of motion
potential energy
energy that matter has because of its location or structure
microscopy
examination of minute objects by means of a microscope, an instrument which provides an enlarged image of an object not visible with the naked eye
phospholipid bilayer
exist as a stable boundary between two adjacent aqueous compartments
ion channels
facilitate the diffusion of ions
aquaporins
facilitate the passage and diffusion of water
desmosomes (anchoring junctions)
fasten cells together into strong sheets; only in animal cells
intermediate filaments
fibers with diameters in a middle range; support cell shape and fix organelles in place
products
final molecules of a chemical reactions
turgid
firm
electron microscopy (EM)
focuses a beam of electrons through a specimen or onto its surface
double helix
form of native DNA
disaccharides
formed when a dehydration reaction joins 2 monosaccharides (i.e. sucrose, lactose, and maltose)
secondary structure
found in most proteins; consists of coils and folds in the polypeptide chain
chloroplast
found in plants and algae, are the sites of photosynthesis; enveloped by a double membrane; contain free ribosomes and circular DNA molecules; grow and reproduce somewhat independently in cells
chitin
found in the exoskeleton of arthropods; provides structural support for the cell walls of many fungi
centrifuge
fractionate/separate cells into their component parts
Why can carbon bond to 4 other atoms?
has 4 valence electrons
unsaturated fats
have 1+ double bonds; typically plant and fish fats
channel proteins
have a hydrophilic channel that certain molecules or ions can use as a tunnel
experimental control
holding constant the variables that an experimenter isn't interested in measuring
surface tension
how difficult it is to stretch or break the surface of a liquid
membrane selectivity
how the membrane adapts to its environment
Van der Waals interactions example
hydrogen bonding
carbohydrates
include sugars and the polymers of sugars
subatomic particles
includes neutrons, protons, and electrons
experimental variables
independent, dependent, and controlled
transmembrane proteins
integral proteins that span the membrane
chemical bonds
interactions that usually result in atoms staying together
thermal energy
kinetic energy associated with the random motion of atoms or molecules; thermal energy in transfer from one body of matter to another
endoplasmic reticulum (ER)
lacks ribosomes; synthesizes lipids; metabolizes carbohydrates; detoxifies drugs and poisons; stores calcium ions surface is studded with ribosomes; distributes transport vesicles; membrane factory for the cell
vacuole
large vesicles derived from the ER and Golgi; only in plant cells
hydrophilic
likes water
flaccid
limp
cohesion
linking together of like molecules; often by hydrogen bonds
steroids
lipids characterized by a carbon skeleton consisting of 4 fused rings
states of matter
liquid (water), solid (ice), gas (vapor)
flagella
long cellular appendage that's specialized for locomotion
polymer
long molecule consisting of many similar building blocks linked together by covalent bonds
primary structure
long, unique chain sequence of amino acids; determined by inherited genetic information
denaturation
loss of a protein's natural structure due to alterations in pH, salt concentration, temperature, or other environmental factors
cell
lowest level of organization that can perform all activities required for life; has a membrane
scientific process
make observations, form hypotheses, test them (revise the hypothesis or make a new one), reject or accept the conclusion
chemical reactions
making and breaking of chemical bonds
saturated fats
maximum number of hydrogen atoms possible and no double bonds; typically, animal fats
natural selection
mechanism for evolutionary adaptations of organisms to their environments
tight junctions
membranes of neighboring cells are pressed together, preventing leakage of extracellular fluid
glucose
most common monosaccharide
cilia
motile cilium is specialized for locomotion or moving fluid past the cell; primary cilium is usually nonmotile and plays a sensory and signaling role
contractile and motor proteins
movement is main function
electrons
negative charge; 1+ electrons move around the nucleus of an atom
anion
negatively charged ion
nucleoside
nitrogenous base (adenine, guanine, thymine, and cytosine) + sugars
neutrons
no charge; found in nucleus of an atom
prokaryotic cell
no nucleus; lacks organelles; single chromosome is coiled into an oval shape
structural formula
notation used to represent atoms and bonding (i.e. H - H)
mass number
number of protons and neutrons
atomic number
number of protons in the nucleus
dehydration reaction
occurs when 2 monomers bond together through the loss of a water molecule
isotopes
one of several forms of an element; same number protons but different number of neutrons - different atomic mass
characteristics of life
order, evolutionary adaptation, regulation, reproduction, respond to their environment, growth and development, process energy
amino acids
organic molecules with amino and carboxyl groups
Producers (Autotrophs)
organism that make their own food (i.e. plants)
Consumer (Heterotrophs)
organisms that need to eat food to obtain their energy (i.e. animals)
evolution
organisms' adaptations to their environment
integral proteins
penetrate the hydrophobic core
Energy is used to:
perform work
polynucleotide
polymer consisting of many nucleotide (DNA/RNA) monomers in a chain
polysaccharides
polymers composed of many sugar building blocks through dehydration reaction; have storage and structural roles
protons
positive charge; found in nucleus of an atom
cation
positively charged ion
gene expression
process of converting information from a gene to a cellular product
defensive proteins
protection against disease; creates antibodies
gap junctions (communicating junctions)
provide cytoplasmic channels between adjacent cells
chemical equilibrium
reached when the forward and reverse reactions occur at the same rate; relative concentrations of reactants and products don't change
concentration gradient
region along which the density of a chemical substance increases or decreases; no work must be done to move substances down the concentration gradient
ATP (adenosine triphosphate)
releases free energy when its phosphate bonds are hydrolyzed
active transport
requires ATP; moves substances against their concentration gradients
receptor proteins
responses of cell to chemical stimuli
quaternary structure
results when a protein consists of multiple polypeptide chains
experiment
scientific test under controlled conditions that involve 1+ factors being manipulated to see the effects if those changes
enzymatic proteins
selective acceleration of chemical reactions
cytosol
semi-fluid portion of the cytoplasm
Stanley Miller's experiment
sent an electrical charge through a flask of a chemical solution of methane, ammonia, hydrogen and water; created organic compounds including amino acids
monosaccharides
simple sugars; simple carbohydrates; molecular formulas that are usually multiples of CH2O; serve as major fuel for cells and as raw material for building molecules
mitochondria
sites of cellular respiration; a metabolic process that uses oxygen to generate ATP; enveloped by a double membrane; contain free ribosomes and circular DNA molecules; grow and reproduce somewhat independently in cells
atoms
smallest unit of matter that retains the properties of an element
selective permeability
some substances can cross more easily than others
phagocytosis
some types of cells can engulf another cell; forms a food vacuole
enzymes
specialized macromolecules that speed up chemical reactions; make or break down polymers
reactants
starting molecules of a chemical reaction
fluid-mosaic model
states that a membrane is a fluid structure with a "mosaic" of various proteins embedded in it; proteins aren't randomly distributed in the membrane
storage proteins
storage of amino acids
glycogen
storage polysaccharide in animals; stored primarily in the liver and muscle cells
covalent bond
strong chemical bond where 2 atoms share 1+ pairs of valence electrons
organic chemistry
study of carbon compounds
biology
study of life
solute
substance that is dissolved into
buffer
substances that minimize changes in concentrations of H+ and OH- in a solution
monomers
subunit that serves as the building block of a polymer
molecular mass
sum of the masses of all the atoms in a molecule
structural proteins
support is main function
cell fractionation
takes cells apart and separates the major organelles from one another; enables scientists to determine the functions of organelles
calorie
the amount of heat required to raise the temperature of 1g of water by 1-degree C
specific heat
the amount of heat that must be absorbed or lost for 1g of that substance to change temperature by 1-degree C
osmoregulation
the control of solute concentrations and water balance, is a necessary adaptation for life in such environments
solvent
the dissolving agent (liquid) of a solution
heat of vaporization
the heat a liquid must absorb for 1g to be converted to gas
lipids
the one class of large biological molecules that doesn't include true polymers; don't mix well with water
diffusion
the tendency for molecules to spread out evenly into the available space (i.e. more concentrated to less concentrated)
microtubules
thickest of the 3 components of the cytoskeleton; shapes the cell; guides movement of organelles; separating chromosomes during cell division; control the beating of flagella and cilia
middle lamella
thin layer between primary walls of adjacent cells; only in plants
microfilaments
thinnest component; bear tension, resisting pulling forces within the cell
facilitated diffusion
transport proteins speed the passive movement of molecules across the plasma membrane; requires no energy
exocytosis
transport vesicle will migrate to the membrane, fuse with it, and release their content outside the cell; secretory cells use this to export their products
RNA (ribonucleic acid)
unique nucleic acids that are essential to protein synthesis
transmission electron microscope (TEM)
used to look at the internal structure of a specimen
deductive reasoning
uses general premises to make specific predictions
independent variable
variable that's being manipulated or changed in an experiment; reveals effects on dependent variable
dependent variable
variable whose value is measured during an experiment; influenced by the independent variable
4 of water's properties
versatile solvent, co/adhesion, ability to moderate temperature, expansion upon freezing
light microscopy (LM)
visible light is passed through a specimen and then through glass lenses; refract (bend) the light to magnify the image
Darwin
wrote "The Origin of Species"; showed evidence of natural selection and descent with modification