organic compounds
contain carbon; examples include lipids, proteins, and carbs
functional groups
amino (NH2), carbonyl (RCOR), carboxyl (COOH),
... [Show More] hydroxyl (OH), phosphate (PO4), sulfhydryl (SH)
fat
glycerol and three fatty acids
saturated fats
bad for you; animals and some plants have it; solidifies at room temp.
unsaturated fats
better for you, plants have it; liquifies at room temp.
steriods
lipids whose structures resemble chicken-wire fence. include cholesterol and sex hormones
phospholipids
glycerol + 2 fatty acids + 1 phosphate group; makes up membrane bilayers of cells; hydrophobic interiors and hydrophillic exteriors
carbohydrates
used by cells for energy and stucture; monosaccharides (glucose), disaccharides (sucrose, maltose, lactose), storage polysaccharides (starch [plants], glycogen [animals]), structural polysaccharides (chitin [fungi], cellulose [arthropods])
proteins
made with the help of ribosomes out of amino acids; serve many functions (transport, enzymes, cell signals, receptor molecules, structural components, and channels)
enzymes
catalytic proteins that react in an induced-fit fashion with substrates to speed up that rate of reactions by lowering the activation energy
competitve inhibtion
inhibitor resembles substrate and binds to active site
noncompetitive inhibition
inhibitor binds elsewhere on the enzyme; alters active site so that the substrate cannot bind
pH
logarithmic scale; <7 acidic, 7 neutral, >7 basic (alkaline); 4 is 10 times more acidic than 5
hydrolysis
breaks down compounds by adding water
dehydration
two components brought together, producing H2O
endergonic reaction
reaction that requires input of energy
exergonic reaction
reaction that gives off energy
redox
electron transfer reactions
cell wall
found in prokaryotes and plant cells eukaryotes; protects and shapes the cell
plasma membrane
found in prokaryotes and eukaryotes; regulates what substances enter and leave a cell
ribosome
found in prokaryotes and eukaryotes; host for protein synthesis; form in nucleolus
smooth ER
found in eukaryotes; lipid synthesis, detoxification, carbohydrate metabolism; contains no ribosomes on cytoplasmic surface
rough ER
found in eukaryotes; synthesizes proteins to secrete or send to plasma membrane; contains ribosomes on cytoplasmic surface
Golgi
found in eukaryotes; modifies lipids, proteins to secrete or send to plasma membrane; contains ribosomes on cytoplasmic surface
mitochondria
found in eukaryotes; power plant of cell; hosts major energy-producing steps of respiration
lysosome
found in eukaryotes; contains enzymes that digest organic compounds; serves as cell's stomach
nucleus
found in eukaryotes; control center of cell; host for transcription, replication, and DNA
peroxisome
found in eukaryotes; breakdown of fatty acids, detoxification of alcohol
chloroplast
found in plant cells eukaryotes; site of photosynthesis in plants
cytoskeleton
found in eukaryotes; skeleton of cell; consists of microtubules, microfilaments, and intermediate filaments
vacuole
large in plant cells and small in animal cells; storage vaults of cells
centrioles
found in animal cells eukaryote; part of microtubule separation apparatus that assits cell division in animal cells
fluid mosaic model
plasma membrane is selectively permeable phosolipid bilayer with proteins of various lengths and sizes interspersed with cholesterol amoung the phospholipids
integral proteins
proteins implanted within lipid bilayer of plasma membrane
diffusion
passive movement of substances down their concentration gradient (from high to low concentrations)
osmosis
passive movement of water from the side of low solute concentration to the side of high solute concentration
facilitated diffusion
assisted transport of particles across membrane (no energy input)
active transport
movement of substances against concentration gradient (low to high concentrations; requires energy input)
endocytosis
phagocytosis of particles into cell through the use of vesicles
exocytosis
process by which particles are ejected from the cell, similar to movement in a trash chute
aerobic respiration
glycolysis -> krebs cycle -> oxidative phosphorylation -> 36 ATP per glucose molecule
anaerobic respiration (fermentation)
glycolysis -> regenerate NAD+ -> 2 ATP per glucose molecule
glycolysis
conversion of 1 glucose molecule into 2 pyruvate, 2 ATP, and 2 NADH; occurs in the cytoplasma, and in both aerobic and anaerobic respiration; must have NAD+ to proceed
Krebs cycle
conversion 1 pyruvate molecule into 4 NADH, 1 FADH2, 1 ATP, H2O, and CO2; occurs twice for each glucose to yeild double the products above; occurs in the mitochondria
oxidative phosphorylation
production of large amounts of ATP from NADH and FADH2; occurs in the mitochrondria; requires the presence of oxygen to proceed
chemiosmosis
coupling of the movement of electrons down the ETC with the formation of ATP using the driving force provided by the proton gradient; occurs in both cell respiration and photosynthesis to produce ATP
ATP synthase
enzyme responsible for using protons to actually produce ATP from ADP
fermentation
process that regenerates NAD+ so glycolsis can begin again; occurs in absence of oxygen
alcohol fermentation
occurs in fungi, yeast, and bacteria; causes conversion of pyruvate to ethanol
lactic acid fermentation
occurs in humans and animal muscles; causes conversion of pyruvate -> lactate; causes cramping sensation when oxygen runs low in muscles
photosynthesis
process by which plants use the energy from light to generate sugar; occurs in chloroplasts; light reactions (thylakoid), and Calvin cycle (stroma)
autotroph
self-nourishing organism that is also known as a producer (plants)
heterotrophs
organisms that must consume other organisms to obtain energy--consmers
transpiration
loss of water via evaporation through the stomata
photophosphorylation
process by which ATP is made during light reactions
photolysis
process by which water is split into hydrogen ions and oxygen atoms (light reactions)
stomata
structure through which CO2 enters a plant, and water vapor and oxygen leave plant
pigment
molcule that absorbs light of a particular wavelength (chlorophyll, carotenoid, phycobilins)
C4 plants
plants that have adapted their photosynthetic process to more efficiently handle hot and dry conditions
C4 photosynthesis
process that first converts CO2 into a 4-carbon molcule in the mesophyll cells, converts that product to malate and then shuttles it to the bundle sheath cells, where the malate releases CO2 and rubisco picks it up as if all were normal
CAM plants
plants close their stomata during the day, collect CO2 at night, and store the CO2 in the form of acids until it is needed during the day for photosynthesis
binary fission
prokaryotic cell division; double the DNA, double the size, then split apart
cell cycle
growth 1 -> synthesis -> growth 2 -> mitosis
cytokinesis
physical separation of newly formed daughter cells of cell division
cell division control mechanisms
growth factors, checkpoints, density-dependent inhibition, and cyclins and protein kinases
growth factors
factors then when present, promote growth, and when absent, impede growth
checkpoints
a cell stops growing to make sure it has the nutrients and raw materials to proceed [Show Less]