ap bio midterm units 1-4

atoms, molecules

_______ & ________ from the environment are necessary to build new molecules.

carbon

_____________ is used to build biological molecules such as carbohydrates, proteins, lipids, and nucleic acids.

storage, cell

carbon is used in ____________ compounds and ______ formation in all organisms. 

nitrogen

_____________ is used to build proteins and nucleic acids.

phosphorus

______________ is used to build nucleic acids and certain lipids.

hydrolysis, dehydration, monomers

______________ and _____________ synthesis are used to cleave and form covalent bonds between _____________.

polymers

structure and function of ______________ are derived from the way their monomers are assembled.

nucleotide

in nucleic acids, biological information is encoded in sequences of ____________ monomers.

five, phosphate, nitrogen

each nucleotide has structural components: a ______-carbon sugar (deoxyribose or ribose), a ___________, and a ___________ base (adenine, thymine, guanine, cytosine, or uracil).

dna, rna

_______ and ______ differ in structure and function.

order, polypeptide, shape

in proteins, the specific _________ of amino acids in a ___________ (primary structure) determines the overall ________ of the protein.

directionality, amino, carboxyl

amino acids have _____________, with an ________ (NH2) terminus and a __________ (COOH) terminus.

hydrophilic, hydrophobic, ionic

the R group of an amino acid can be categorized by chemical properties (______________, ______________, or _______),

structure

the interactions of R groups determine ____________ and function of that region of the protein.

carbohydrates

 complex __________________ comprise sugar monomers whose structures determine the properties and functions of the molecules. 

lipids

_________ are nonpolar macromolecules.

saturation

differences in _________________ determine the structure and function of lipids

phospholipids, polar

_________________ contain polar regions that interact with other _________ molecules, such as water, and with nonpolar regions that are often hydrophobic. 

subcomponents

directionality of the _________________ influences structure and function of the polymer.

covalent, carboxyl

proteins comprise linear chains of amino acids, connected by the formation of ________________ bonds at the ___________ terminus of the growing peptide chain.

amino

proteins have primary structure determined by the sequence order of their constituent ________ acids.

folding, alpha, beta

proteins have secondary structure that arises through local ___________ of the amino acid chain into elements such as _______-helices and ______-sheets.

three, free

proteins have tertiary structure that is the overall ________-dimensional shape of the protein and often minimizes _______ energy.

polypeptide

proteins have quaternary structure that arises from interactions between multiple ____________ units.

carbohydrates

__________________ comprise linear chains of sugar monomers connected by covalent bonds.

polymers

carbohydrate ______________ may be linear or branched.

ribosomes

________________ comprise ribosomal RNA (rRNA) and protein. 

smooth, rough

endoplasmic reticulum (ER) occurs in two forms—_________ and _________. 

rough

____________ ER is associated with membrane-bound ribosomes.

rough

_________ ER compartmentalizes the cell.

smooth

_________ ER functions include detoxification and lipid synthesis.

golgi

the ________ complex is a membrane-bound structure that consists of a series of flattened membrane sacs

golgi

functions of the _________ include the correct folding and chemical modification of newly synthesized proteins.

mitochondria, smooth

_______________ have a double membrane. The outer membrane is _______________, but the inner membrane is highly convoluted, forming folds.

lysosomes, enzymes

_______________ are membrane-enclosed sacs that contain hydrolytic _____________. 

vacuole, plants

a ___________ is a membrane-bound sac that plays many and differing roles. In __________, a specialized large vacuole serves multiple functions. 

chloroplasts, double

_____________ are specialized organelles that are found in photosynthetic algae and plants, and have a ________ outer membrane.

function

organelles and subcellular structures, and the interactions among them, support cellular ________.

mechanical, protein, intracellular

endoplasmic reticulum provides ____________ support, carries out _________ synthesis on membrane-bound ribosomes, and plays a role in ____________ transport.

metabolic

mitochondrial double membrane provides compartments for different ____________ reactions.

enzymes, digestion, recycling

lysosomes contain hydrolytic _________, which are important in intracellular ____________, the ___________ of a cell’s organic materials, and programmed cell death (apoptosis). 

increases, atp

the folding of the inner membrane __________ the surface area, which allows for more _____ to be synthesized.

thylakoids, stroma

within the chloroplast are __________ and the _________.

grana

thylakoids are organized in stacks, called _______.

pigments, proteins

membranes contain chlorophyll _________ and electron transport _________ that comprise the photosystems.

dependent

the light-______________ reactions of photosynthesis occur in the grana.

stroma

the _________ is the fluid within the inner chloroplast membrane and outside of the thylakoid.

stroma

the carbon fixation (calvin-cycle) reactions of photosynthesis occur in the _________.

mitochondria

the krebs cycle (citric acid cycle) reactions occur in the matrix of the ______________.

mitochondrial

electron transport and ATP synthesis occur on the inner ______________ membrane.

wastes

organisms have evolved highly efficient strategies to obtain nutrients and eliminate ________.

exchange, surrounding

cells and organisms use specialized __________ surfaces to obtain and release molecules from or into the ____________ environment.

phospholipids

_______________ have both hydrophilic and hydrophobic regions.

hydrophilic

the ____________ phosphate regions of the phospholipids are oriented toward the aqueous external or internal environments.

hydrophobic

the ______________ fatty acid regions of the phospholipids face each other within the interior of the membrane. 

embedded

_____________ proteins can be hydrophilic, with charged and polar side groups, or hydrophobic, with nonpolar side groups.

steriods, glycoproteins, glycolipids

cell membranes consist of a structural framework of phospholipid molecules that is embedded with proteins, ___________ (such as cholesterol in eukaryotes), ____________, and ____________ that can flow around the surface of the cell within the membrane.

selective

the structure of cell membranes results in ____________ permeability. 

separate

cell membranes __________ the internal environment of the cell from the external environment.

selective

___________ permeability is a direct consequence of membrane structure, as described by the fluid mosaic model.

nonpolar

small _____________ molecules, including N2, O2, and CO2 , freely pass across the membrane.

polar

hydrophilic substances, such as large __________ molecules and ions, move across the membrane through embedded channels and transport proteins.

polar, h2o

_________ uncharged molecules, including ______, pass through the membrane in small amounts.

cell walls

________ _______ provide a structural boundary, as well as a permeability barrier for some substances to the internal environments. 

carbohydrates

cell walls of plants, prokaryotes, and fungi are composed of complex ______________.

high, low

passive transport is the net movement of molecules from ____ concentration to ______ concentration without the direct input of metabolic energy.

passive

__________ transport plays a primary role in the import of materials and the export of wastes.

low, high

active transport requires the direct input of energy to move molecules from regions of ____ concentration to regions of ____ concentration.

selective

the ___________ permeability of membranes allows for the formation of concentration gradients of solutes across the membrane.

energy, large

the processes of endocytosis and exocytosis require ________ to move ________ molecules into and out of cells.

exocytosis

in _____________, internal vesicles fuse with the plasma membrane and secrete large macromolecules out of the cell.

endocytosis

in _______________, the cell takes in macromolecules and particulate matter by forming new vesicles derived from the plasma membrane.

diffusion

membrane proteins are required for facilitated ___________ of charged and large polar molecules through a membrane

aquaporins

large quantities of water pass through ______________. 

channel

charged ions, including Na+ and K+, require __________ proteins to move through the membrane.

polarized

membranes may become ____________ by movement of ions across a membrane.

active

membrane proteins are necessary for _________ transport. 

metabolic, active

____________ energy (such as from ATP) is required for _________ transport of molecules and/ or ions across the membrane and to establish and maintain concentration gradients. 

maintenance

the Na+/K+ ATPase contributes to the _________________ of the membrane potential.

external

___________ environments can be hypotonic, hypertonic or isotonic to internal environments of cells.

osmosis

water moves by ____________ from areas of high water potential/low osmolarity/ low solute concentration to areas of low water potential/high osmolarity/high solute concentration.

high, low

______ water potential—>_____ water potential

low, high

______ osmolarity—>_____ osmolarity

low, high

______ solute concentration—>_____ solute concentration

pressure potential

Ψp

solute potential

Ψs

water potential

_______ = Ψs + Ψp

movement

growth and homeostasis are maintained by the constant ___________ of molecules across membranes.

osmoregulation

_________________ maintains water balance and allows organisms to control their internal solute composition/water potential.

solute potential of a solution

Ψs = −iCRT 

ionization constant

i

molar constant

c

pressure constant

r (0.0831)

temperature

t (in kelvin (°C + 273))

across

a variety of processes allow for the movement of ions and other molecules __________ membranes, including passive and active transport, endocytosis and exocytosis.

intracellular, enzyme

membranes and membrane-bound organelles in eukaryotic cells compartmentalize ____________ metabolic processes and specific ____________ reactions. 

internal

____________ membranes facilitate cellular processes by minimizing competing interactions and by increasing surface areas where reactions can occur.

endosymbiosis

membrane-bound organelles evolved from once free-living prokaryotic cells via ________________.

prokaryotes

__________________ generally lack internal membrane bound organelles but have internal regions with specialized structures and functions. 

substrate

the structure of enzymes includes the active site that specifically interacts with ________ molecules.