AP BIO exam
purpose of phosphorylation
-energize, change shape -make things more likely to react NAD+= electron shuttle, takes electrons to ETC
Lysosomes
-eukaroytic animal cells -contain hydrolytic enzymes which are important in intracellular digestion, the recycling of a cell's organic materials and programmed cell death (apoptosis)
Cilia
-eukaryotes of animal cells -keep airways clear of mucus
Mitochondria
-eukaryotic plant and animal cells Powerhouse of the cell, organelle that is the site of ATP (energy) production
steps of cellular respiration
1. Glycolysis- occurs in cytoplasm 2. Pyruvate oxidation- occurs in mitochinra 3. Krebs Cycle- occurs in mitochonria 4. Electron Transport Chain- occurs in mitochondria
Phases of the cell cycle
1. Interphase (G1, S, G2) 2. Mitosis (PMAT) 3. Cytokinesis (cell division)
Membrane fluidity is affected by
1. Lipid composition: short unsaturated chains increase fluidity 2. Temperature: fluidity decreases in colder conditions
Properties of Carbon
*Carbon has 4 valence electrons = 4 bonds * Can form long chains * Makes organic compounds when bonded with hydrogen The properties of carbon that make it so important are its ability to bond to four other atoms and the diversity it can get from its differing skeletons.
Anerboic Respiration
- pathway that use something other than O2 as the final electron acceptor -in bacteria, final electron acceptor can be Nitrogen or sulfur -in these bacteria you have glycolysis, elctrons, ETC, final acceptor, producsed 24-26 ATP
light dependent reactions of photosynthesis in eukaryotes involve a series of pathways
- LDR capture light energy by using light absorbing molecules called pigments -pigments help transform light energy into chemical energy -chemical energy is temporarily stores in chemical bonds of carrier molecules called NADPH -LDR help facilitate ATP synthesis -ATP and NADPH transfer stored chemical energy to power the production of organic molecules in another pthway called Calvin cycle, -oxygen is produced as a result of water hydrolysis
Photosynthesis
- biological process that captures energy from the sun and prodcues sugars
fermentation and cellular repsiration are processes that allow organisms to use energy stored in biological macromolecules
- cellular respiration and fermentated are characterist of all forms of life -CR and F release chemical energy from organic molecules like gluclose - O2 is not used during the process of F but is used during CR -F and anerboic repisration are not the same processes
in CR, decoupling oxidative phosphorylation from ETC generates heat
- energy is stored in proton gradients -decoupling OP from ETC refers to proton gradient NOT being used by ATP synthase to produce ATP -when decoupling occurs the energy stored in the gradient is released as heath -the heat from decoupling can be used by endothermic organisms to regulate body temp
ETC transfers energy from electrons
- membrane proteins make up ETC -facilitate a series of coupled reactions using energy from electrons -high ener
Prokaryotic
- no nucleus - no membrane bound organelles - dna in nucleoid -cell wall
Eukaryotic
- nueclus - membrane bound organelles - no cell wall - larger - DNA in nucleus
Krebs Cycle (Citric Acid Cycle)
- takes place in the matrix of the mitochondria. - two acetyl coenzyme A molecules enter the cycle and combine with oxaloacetate to form citric acid, which then loses two carbons as carbon dioxide. -The cycle is now ready to begin again with the second Acetyl CoA. -For each Acetyl CoA, the Krebs Cycle produces 1 ATP, 3 NADH, and 1 FADH2. -CO2 is relased from intermediate reactoins -high energy electrons transferred to NADH and FADH2 -ADP phosphorlyated to ATP completes the breakdown of glucose by oxidizing a derivative of pyruvate to carbon dioxide.
the flow of protons by chemiosmois through ATP synthase drives ATP synthesis
- the process of making ATP using the stored energy of a proton gradient is referred to as oxidative phosphorlyation -NADH and FADH2 lose high energy electrons to the ETC (oxidatoin) -ATP synthase adds Pi to ADP resultin in an ATP molecule (phosphorylatoin)
membrane potential
-The voltage across a cell's plasma membrane. - small but significant - acts like a battery, an energy source that affects the traffic of all charged substances (ions) across the membrane - inside is negative compared to outside - favors that passive transport of cations into the cell and anions out of the cell
Chloroplast
-eukaryotic plant cells -site of photosynthesis -convert solar energy to chemical energy by synthsizing glucose into CO2 and H20. consists of stacks of thylakoid called granum. - fluid (stroma) contains DNA, ribosomes, and enzymes
Golgi apparatus
-eukaryotic plants and animals -responsible for receiving, sorting transporting, modifying, packaging and shipping proteins, lipids or products from ER Into vesicle for delivery to certain places for other functions to be carried out -folds proteins into correct conformation to be usable -can add side chains to proteins -glycosylation adds carb chains resulting in glycoprotein
Flagellum
-in pro and eukaryotic animal cells -propels cell -rotary movement in prokaryotic and bending movement in eukaryotic
smooth er
-lacks ribosomes -synthesize lipids, metabolize carbs, detoxification of drugs and alcohol, storage of Ca+ -enzymes help snytheize lipids, steroids, and new membrane phospholipids. in eukaryotic plant and animal
why are cells so small?
-need to maintain a high surface area to volume ratio -surface area of cell=cell membrane which regulates nutrients going in and waste going out
passive transports including 3 types
-net movement of molecules from high low concentration w/o energy. -plays primary role in import of materials and export of wastes diffusion, osmosis, facilitated diffusion
ETC
-occurs in the inner membrane of the mitochondria and chloroplasts, and cell membranes of prokaryotes -facilties a series of coupled reactions during cellular respiration -allows for amore controlled and efficient transfer of energy -uses electron energy to establish electrochemical/proton graidents across membranes -electrones are delivered by electron carries, NADH and FADH2 to ETC - atp synthase uses graident to synthesis atp
Rough ER
-present in eukaryotic plant and animal cells -has ribosomes -makes secretory proteins: glycoproteins -membrane factory of cells -makes membrane phospolipids
Vaculoes
-storage and release of macromolecules and cellular waste products -in plants it aids in retention of water for turgor pressure -in pro and eukaryotic plant and animal cells -small membrane structure -alter cell activity
cellular respiration
-transfer of energy from food moelcules to ATP mocules -energy is in the bonds -bonds results from the share of electrons or transfer electrons -energy tends to be related to the electrons
How Miller and Urey tested the Oparin-Haldane hypothesis and what they learned.
. Miller and Urey's experiment tested Oparin and Haldane's hypothesis. They created conditions comparable to those in Oparin and Haldane's hypothesis. A warmed flask of water stimulated the primeval sea, which sent the water vapor into another flask filled with the components of early earth's atmosphere. The "atmosphere" consisted of H20, H2, CH4, and NH3, the gases that researchers believed prevailed in the ancient world. Sparks were discharged in the synthetic atmosphere to mimic lightning. A condenser cooled the atmosphere, raining water and any dissolved compounds back to the miniature sea. As material circulated through the apparatus, the solution from them changed from clear to murky brown. The contents were analyzed and a variety of organic compounds were found such as some of the amino acids that make up the protein of organisms. These results support Oparin and Haldane's hypothesis about life on earth because they said that inorganic molecules could produce organic ones by the material in the atmosphere with the help of lightning, or another energy source and indeed it could.
pyruvate in mitochondria (pyruvate oxidation) CR
1. 3C pyruvate because 2C Acetyl Coa. Co2 is released and NADH is formed 2. Acetyl CoA enters Krebs-> 3 NADH formed, 1 FADH2 formed, 2 CO2 released, 1 ATP produced by substrate level phosphorylation *for glucose ug et x2 of everything, so 6NADH, 2 FAH2 etc... •actively transported through mitochondiral membranes into matrix *oxidized and a product of pyrvuate oxidation
Four unique properties of water and how each contributes to life on Earth
1. Cohesion- Allows water to stick together2. Adhesion- Allows water to get around organism against gravity.3. High specific heat- Keeps the oceans from boiling and freezing, keeping a favorable climate for marine life.4. Floating ice- Keeps freezing of water only surface deep, allowing all life to exist.
The catalytic cycle of an enzyme that results in the production of a final product.
1. Substrates enter the active site, and the enzyme changes shape to embrace the substrates2. Substrates held in the active site by weak interactions3. Active site can lower activation energy and speed up a reaction by acting as a template for substrate orientation, stressing the substrates and stabilizing the transition stae, providing a favorable microenvironment, or participating directly in the caralytic reaction.4. Substrates are.converted into products5. Products are released
solution to SA:V ratio problem
1. cell divides 2. infolding of cell membranes to produce endomembrane system: golgi, er, nucleus. increases SA but also causes compartmentalization
Fitness, cell variation
1. fitness refers to ability to survive and produce 2. variation at the molecular level provides organisms w/ ability to respond to a variety of environmental stimuli 3. variation at the molecular level can provide organisms w/ fitness advantages under changing environment conditions
how can we measure the rate of cellular respiration
1. rate of O2 produced 2. rate of CO2 consumed 3. measure decrease of absorbency of a DPIP solution - DPIP starts out blue. when it gets reduced (gains electrons) it becomes clear
products of glycolysis
2 pyruvate, 2 ATP, 2 NADH
Heterotroph
organism that obtains energy from the foods it consumes; also called a consumer
covalent bond
A chemical bond that involves sharing a pair of electrons between atoms in a molecule
Photosystem 1 (PS1)
A light capturing enzyme in the thylakoid membrane of a chloroplast; reduces NADP+ to NADPH.
food vaculoes
A membranous sac formed by phagocytosis of microorganisms or particles to be used as food by the cell
Nucleus
A part of the cell containing DNA and RNA and responsible for growth and reproduction. ONLY in eukaryotic cell. enclosed by nuclear envelope: double membrane surrounding nucleus.
C4 plants
A plant in which the Calvin cycle is preceded by reactions that incorporate CO2 into a four-carbon compound, the end product of which supplies CO2 for the Calvin cycle. plants that have adapted their photosynthetic process to more efficiently handle hot and dry conditions
C3 plants
A plant that uses the Calvin cycle for the initial steps that incorporate CO2 into organic material, forming a three-carbon compound as the first stable intermediate. the most common and the most efficient at photosynthesis in cool, wet climates do not separately fix CO2 and use Rubisco in Calvin Cycle
electron transport chain
A sequence of electron carrier molecules (membrane proteins) that shuttle electrons during the redox reactions that release energy used to make ATP.
Pinocytosis
A type of endocytosis in which the cell ingests extracellular fluid and its dissolved solutes.
Enzymes work by lowering activation energy
Activation energy is the amount of energy necessary for a chemical reaction to occur, enzymes are catalysts and will speed up the reaction, thus lowering the activation energy.
How different cell types show differences in subcellular components
Animal cells have: lysosomes, centrioles, and flagella.Plant cells have: chloroplasts, central vacuole and tonoplast, cell wall, and plasmodesmata.
Peroxisomes
Break down fatty acids and produce hydrogen peroxide
are there any cells that produce energy for other cells to use?
no. cells make their won energy through glycolysis (splits sugars) and cellular respiration (mitochondira, chloroplasts)
cellular respiration in eukaryotes involves a series of coordinated enzyme catalysed reactions that capture energy from biological macromoecles
CR involved release of chemical energy throuh break down of glucose and create ATP
The cellular functions of carbohydrates, lipids, proteins, and nucleic acids.
Carbohydrates serve as fuel and building material Lipids (hydrophobic) Stores energy Proteins (unique conformations) Enzymatic, storage, hormonal, transport, structural Nucleic Acids- Store and transmit hereditary information
How the sequence and subcomponents of the four groups of organic compounds determine their properties
Carbohydrates: CH2O or C:H:O have Carbonyl group (C=O) and hydroxyl groups (-OH).Lipids: consists of hydrocarbon regions (H-C)Protein: All amino acids have carboxyl groups and amino groups.Nucleic acids: phosphate group, Pentose group, and Nitrogenous base.
Why membranes are selectively permeable
Cell membrane allows certain substances through while others cannot. direct consequences of membrane structure (fluid mosaic model)
Centrioles
Cell organelle that aids in cell division in eukaryotic animal cells only
How changes in these organic molecules would affect their function
Changes at any level can affect the protein because since its shape is unique to its function, they will be linked, making any change, will make a new protein with a new function
How changes in pH can alter biological systems
Changes in pH can alter biological systems, in the way that raising or lowering the pH level of cells, which is close to 7, will change the concentration of hydrogen and hydroxide ions, which the cell is sensitive to.
enzyme inhibitors
Competitive inhibitors: compete for the active site. take up space and slow rate. Noncompetitive inhibitors: change the shape of the active site. slow rate by making bonding impossible allosteric inhibitors and attractors can stabilize or destabilize
Pyruvate dehydrogenase complex (PDC)
Contains enzymes that convert pyruvate into acetyl coA PDC is located in the mitochondrial matrix There is a shuttle that brings pyruvate into the mitochondria. What would happening the cell if the shuttle was broken? Pyruvate would not enter mitochondria No Krebs cycle, no etc, much less ATP Pyruvate in cytoplasm undergoes fermentation forming lactic acid and 2 ATP
Osmosis
Diffusion of water through a selectively permeable membrane. small amounts move slowly though bilayer. most water moves through pores caled AQUAPORINS
metabloism, fermentation problem #3
During exertion, our muscles produce lactic acid from pyruvate by fermentation, allowing the regeneration of NAD+ for continued ATP production by glycolysis. Because lactic acid metabolism is blocked by tremetol, the acid would build up in our blood, decreasing the pH.
which macromolecules have phosphorus
nucleic acids
what happens to chlorophyll electrons when light absorption occurs and what is the importance of this?
electrons will be energzied. the energy from electrons will be used to establihs a proton gradient and reduce NADP+ to NADPh
How does ATP provide energy?
Energy is released when an ATP molecule is broken into an ADP molecule and an inorganic phosphate
enyzmes
Enzymes are proteins, so their final conformation is affected by the interactions between their R-groups. ·The shape of an enzyme and its active site determine its activity. Enzymes work by lowering the energy of activation. Enzymes are specific in the reactions they catalyze because of the molecular shape of their active site.
Transpiration
Evaporation of water from the leaves of a plant
second law of thermodynamics
Every energy transfer or transformation increases the disorder of the universe.
The major production of ATP during aerobic metabolism occurs when electrons from __________ and _____________ are transferred to _______________.
FADH2, NADH, O2 After the citric acid cycle, the majority of energy is stored in the reduced electron carriers NADH and FADH2. Electrons from the carriers are donated to the electron transport chain in the mitochondrial inner membrane and are ultimately transferred to oxygen to produce water. The proton gradient that is produced during this process can generate ATP by passing through the inner mitochondrial membrane associated ATP synthetase.
Microvilli
Fingerlike extensions of plasma membrane of apical epithelial cells, increase surface area, aid in absorbtion, exist on every moist epithelia, but most dense in small intestine and kidney
Nucleolus
Found inside the nucleus. Ribosomal Rna synthesis. also sense cellular stress found in plant and animal cells. only in eukaryotic.
which stage is the stage where cell no longer divides
G0
why is the hydrolysis of water necessary?
H molecules from splitting of water are released into the thylakoid space and used to create a gradient
the importance of hydrogen bonding to the properties of water
Hydrogen bonding is important to the properties of water because its collective holding of water allows in cohesion, the binding together of like materials. Also, it is important because it gives water a high specific heat.
Why is DNP dangerous?
If electron transport doesn't produce ATP, then much more sugar must be metabolized for energy needs. Very low production of ATP would be lethal. In oxidative phosphorylation, the flow of electrons from NADH and FADH2 to oxygen results in the pumping of H+ from the matrix to the inner membrane space. This gradient of H+ can produce ATP by flowing through ATP synthetase in the mitochondrial inner membrane. Dinitrophenol disrupts the H+ gradient reducing ATP synthesis. Under these conditions, much of our food that we eat could not be used for ATP synthesis are we lose weight. However, too much inhibitor and we could make too little ATP for life. The difference between weight loss and death is only a small concentration change in dinitrophenol, making the drug dangerous.
How does wind affect transpiration?
Increases the rate of transpiration because humid air near the stomata is carried away
which macromolcues have nitrogen
nucleic acids and proteins
where does glycolysis occur?
It occurs in the cytoplasm
Explain why in anaerobic cells the ratio of pyruvate/ lactate is much less than 1 while under aerobic conditions the ratio of pyruvate/ lactate is much greater than 1.
Lactate is produced from pyruvate only under anaerobic conditions. The glycolytic pathway produces pyruvate, which in the presence of oxygen will be further metabolized in the citric acid cycle to produce NADH and FADH2 for oxidative phosphorylation in the mitochondria. Normally, lactic acid will be low under these conditions. In the absence of oxygen (anaerobic), pyruvate must be converted to lactic acid, the only reaction that can regenerate NAD+ allowing further glycolysis. The production of lactic acid only under anaerobic conditions explains why pyruvate/lactate is much less than 1 in anaerobic cells and much greater than one in aerobic cells.
difference between lactic acid and alcoholic fermentation
Lactic: pyruvate is final electron acceptor in glycolysis. in the process, NAD+ forms from NADH. NAD+, in turn, lets glycolysis continue. This results in additional molecules of ATP. Alcoholic: pyruvate changes to alcohol and carbon dioxide allowing glycolysis to continue making ATP. This type of fermentation is carried out by yeasts and some bacteria
how does light affect transpiration?
Light affects transpiration by opening the stomata; the more intense the light the more it widens, this allows more water vapour to diffuse out of the stomata.
Which checkpoint is responsible for mkaing sure nonjisduction tkaes place
M checkpoint
simple diffusion
Movement of molecules from an area of higher concentration to an area of lower concentration. -small, non polar molecukes through lipid bilayer: O2, CO2,
facilitated diffusion
Movement of specific molecules across cell membranes through protein channels. specific protein carrier charged ions like Na+ and K+ need channel proteins. membranes may become polarized by movement of ions across membrane
How a cell response in the nucleus turns on genes whereas in the cytoplasm it activates enzymes.
Nucleus:- many pathways ultimately regulate protein synthesis by turning on or off specific genes in the nucleus.- this is achieved by transcription factors that are necessary to begin the first step of protein synthesisCytoplasm: signaling may regulate the activity of a protein rather than its synthesis, which affects cellular activity in the cytoplasm.
what do endocytosis and exocytosis do?
enable patches of membrane to flow back and forth between interior of cell and plasma membrane
A scientific hypothesis about the origin of life on Earth
Oparin-Haldane hypothesis suggests that life arose gradually from inorganic molecules, with "building blocks" like amino acids forming first and then combining to make complex polymers
what is the function of oxygen in cellular respiration
Oxygen is the final electron acceptor of the electron transport chain in the final step of cellular respiration. Oxygen combines with electrons and hydrogen ions to produce water.
The role of water potential in predicting movement of water in plants
Plants use water potential to transport water to the leaves so that photosynthesis can take place. The internal water potential of a plant cell is more negative than pure water; this causes water to move from the soil into plant roots via osmosis..
Chemiosmosis
Process by which a Hydrogen pump pumps protons into the thylakoid membrane. H+ passively flows through the ATP synthase which leads to the creation of ATP.
How proteins reach their final shape (conformation), the denaturing impact that heat and pH can have on protein structure, and how these changes may affect the organism.
Proteins reach their final shape when they fold spontaneously and based on previous forming factors, like where ionic bonds can form, where disulfide bridges are, if its alpha helix or a beta pleated sheet. Heat and pH can stop the funcuon of the protein, making it denatured, and having a inactive protein in the organism.
Photorespiration
Reaction in which rubisco attaches oxygen instead of carbon dioxide to ribulose bisphosphate
Three stages of cell communication: reception, transduction, and response. (Cell Communication)
Reception: the target cell's detection of a signal molecule coming from outside the cell. Transduction: the conversion of the signal to a form that can bring about a specific cellular response. Response: the specific cellular response to the signal molecule.
Role of proteins in membranes
Serve as transport channels to move materials across the hydrophobic interior of the phospholipid bilayer, or as molecular receptors to bind the signaling molecules.
dif between endocytosis and exoctysoisis
endocytosis inolves phagocytosis or pincocytosis to bring matierals in cell
Vesicle
Small membrane-bound sac that functions in moving products into, out of, and within a cell.
How is ATP produced in glycolysis?
Substrate Level Phosphorylation - Enzyme catalyzed transfer of a phosphate group from a phosphorylated substrate to ADP where a substrate of glycolysis donates a phosphate to ADP, occurs in two steps of the second-half of glycolysis to produce ATP 4 ATP produced by substrate level phosphorlyation (results in net gain of 2 ATP as 2 were used in the energy investment stage)
How internal membranes and organelles contribute to cell functions
The cell creates specialized environments for specific functions. These compartments can be organelles, specific structures that take on sets of tasks within the cell which allows the cell to function correctly and efficiently.
electromechanical gradient
The combined gradient of concentration and electrical charge that affects an ion
what factors affect diffusion
The concentration gradient, The Temperature, The Surface Area Of the membrane
cotransport
The coupling of the "downhill" diffusion of one substance to the "uphill" transport of another against its own concentration gradient. uses ATP symport: molecules move in same direction antiport: molecules move in opposite directions
the role of dehydration synthesis in the formation of organic compounds and hydrolysis in the digestion of organic compounds
The dehydration reactions makes a monomer by creating a covalent bond between two molecules with a water molecule loss.Polymers are broken down with they add a water molecule, removing the covalent bond between the two molecules.
Exocytosis
The movement of materials out of the cytoplasm of a cell by the fusion of vesicles with the plasma membrane. pancreas!
relationship of molarity to osmotic concentration
The osmotic pressure of a solution is proportional to the molar concentration of the solute particles in solution
Bulk flow functions in long-distance transport
Water and solutes move through xylem vessels and sieve tubes by bulk flow, the movement of a fluid driven by pressure. requires energy.
proton gradient
The product of the electron transport chain. A higher concentration of protons outside the inner membrane of the mitochondria than inside the membrane is the driving force behind ATP synthesis. a gradient formed by the difference in proton concentrations across a membrane
oxidative phosphorylation
The production of ATP using energy derived from the redox reactions of an electron transport chain; the third major stage of cellular respiration. *responsible for most ATP production in cellular respiration *pathway ultilizing ETC, chemiosmisis and ATP synthase to make ATP -located in ETEC -proteins recieve electrons from NADH and FADH2, so they are first reduced and then oxidized -oxidation-reduction reactions provide energy to pump protons into intermembrane space -membranes of mitochondria are not permeable to H+. they produce a proton motive force, that is the concentration gradient of proteins -they have to pass through a protein channel called ATP synthase to get out of intermembrane -protons moving through ATP synthase provide energy to spin ATP synthase that then allows ADP and P to join to form ATP -electrons end up being accepted by 02 and join w/ h+ to make H20
What determines the shape of a protein?
The sequence of amino acids and whether or not it is hydrophobic or hydrophilic
How a receptor protein recognizes signal molecules and starts transduction
The signal molecule is complementary in shape to a specific site on the receptor and attaches there. The binding of a specific signal molecule to a receptor in the plasma membrane triggers the signal transduction.
what happens when a molecule is phosphorylated
The transfer of a phosphate group, usually from ATP, to a molecule. Nearly all cellular work depends on ATP energizing other molecules by phosphorylation.
How does humidity affect transpiration?
When the air is more humid, it is harder for the water to evaporate into the air. (More humidity = less transpiration)
How does temperature affect enzyme activity?
a. as temperature increases, so does the rate of reaction because the molecules are moving faster and have a higher chance of hitting eachother b. at extremely high temperatures, the enzyme is denatured due to disruption of noncovalent bonds c. lower temperatures the substrate molecules do not have enough kinetic energy for the reaction to take place even in the presence of the enzyme
How does pH affect enzyme activity?
a. changes shape of enzyme by interacting with noncovalent bonds b. also changes shape or charge properties of the substrate so that either the substrate cannot bind to the active site or it cannot undergo catalysis c. As pH increases, enzyme activity increases until it reaches an optimal point in which enzymes denatures and as pH increases, enzyme activity decreases.
The importance of buffers in biological systems
allows biological fluids to maintain a relatively constant pH despite the addition of acids or bases.
which is not a nomemer of neuclic acid
amino acid
2 types of metabolism
anabolism - building up process, synthesis of ATP, requires energy expenditure. energy is goign into making bonds. ex: photosynthesis catabolism - breaking down process. ex: cellular respiration, breaks sugar down into smaller molecules
relationship between cell size and SA:V ratios
as cells increase in size, SA:V ratio decrease
C4 do not undergo photo respiration bcuz pepco binds to CO2 In C3 rubisco binds withs O2 for photo respiration
bio nootes
Autotroph
capture energy from physic sources like sunlight or chemical sources and transform that energy into energy sources usable by all cells
Phagocytosis
carried out by lysosomes; intracellular digestiona type of endocytosis in which large particulate substances or small organisms are taken up by a cell.lysosomes digest (hydrolyze) materials taken into the cell. type of endocytosis
Function of Rubisco
catalyzes CO2 + RuBP = 6C, It is an enzyme that catalyzes the reaction of RuBP with CO2 in the first step of carbon fixation.
What do all cells have?
cell membrane, DNA, ribosomes, cytoplasm
understanding SA:V ratio
cells use nutrients by its volume and accumulates waste by its volume. so as it grows, volume increases faster than surface area so cell is not able to get enough nutrients to feed itself and volume can't get ride of waste fast enough - cell increase, SA decrease. SA takes in nutrients and gets ride of waste -Volume uses nutrients and produces waste
movemnet of water
cells w/ 1.0 M concentration will gain water from 0.5M exterior soln
which of the following results from water hydrogen bonding?
cohesion, adhesion, surface tension
Endoplasmic Reticulum
consists of network of membranous tubules and sac called cisternae. provides mechanical support, carries out protein synthesis on membrane bound ribosomes, plays role in intracellular transport
the types of chemical bonds and how they form
covalent, polar, ionic, non polar, hydrogen,
Role of carbohydrates in membranes
crucial in cell-cell recognition (necessary for proper immune function) and in developing organisms (tissue differentiation).The reason blood transfusions must be type-specific.
Mitosis results in
daughter cells with the same number and composition of chromosomes. diploid
how does the dark affect transpiration?
decreases transpiration. stomata closed.
describes the forming of a bond between monomers w/ the removal of a water molecule
dehydration
role of mitosis
development and growth, repair, tissue renewal, asexual production
what is an electrochemical/proton gradient
difference in concetration of prtons (H+ ions) across a membrane
Directionality influences structure and function of polymers, such as nucleic acids (5' and 3' ends) and proteins (amino and carboxyl ends)
directionality determines the direction of DNA replication and transcription- proteins rely on this order an directionality to be properly sequenced
ATP synthase can produce ATP using as a direct energy source:
energy from a proton gradient established in mitochondria The electrons from from NADH and FADH2 flow through the electron transport chain in the inner mitochondrial membrane generating a H+ buildup in the inner membrane space. This proton gradient (gradient of H+) flowing through the membrane enzyme complex ATP synthetase is the direct energy source for producing ATP.
ATP synthase
enzyme that creates ATP when protons pass through the enzyme
How feedback inhibition is use to maintain appropriate levels of enzyme products in a pathway.
enzymes converted into different enzymes, new enzyme acts as an inhibitor to its own production so there is no excess buildup (maintain homeostasis)
fermentation allows glycolysis to proceed in the absence of oxygen
ethanol and lactic acid are byproduct of fermentation
membrane fluidity
extent to which lipid molecules can move in the plane of the membrane
cell membrane model
fluid mosaic model: protein is in sea of phospolipids; phospholipid bilayer - 2 layers of phospholipids, heads are hydrophilic and face outwards towards water inside and outside of cells. tails hydrophobic and face each other -layer has consisiteny of oil -proteins are partially or wholly embedded in membrane -membrane allows cells to establish and maintain internal environments that are dif from external environments
Phosphoenolpyruvate carboxykinase
generates a high phosphoryl transfer potential compound Oxaloacetate -> phosphoenolpyruvate Gluconeogenesis, irreversible enzyme In cytosol Requires GTP oxaloacetate to phosphoenolpyruvate C4 species PEPCO catalyzes the first carboxylation reaction of C4 photosynthesis in the mesophyll cells C4 plants generally have high PEPCO activity in the cytosol of mesophyll cells, allowing for the accumulation of four-carbon acids that subsequently diffuse into the bundle sheath cells (BSCs) for decarboxylation The specialized biochemistry and leaf anatomy of C4 plants results in CO2 partial pressure around the site of Rubisco severalfold higher than current atmospheric levels, significantly reducing the rates of photorespiration.
Location for Light-Dependent Reactions
grana/thylakoid memrbane
antiduretic hormone
hormone that maintains water balance in the body by increasing water reabsorption in the kidneys
describes the breaking of a bond w/in a polymer using water
hydrolysis
charactres of a membrane bound protein
hydrophilic R group exterior and hydrophiic R group interenior
ribosomes
in plant and animal. pro and eukaryotic. made of ribosomal rna and protein. ceulllar components that carry out proton synthesis. free ribosomes are suspended in cytosol, bound ribosomes attached to outside of ER or nuclear envelope
How does enzyme concentration affect enzyme activity?
increasing enzyme concentration will speed up the reaction, as long as there is substrate available to bind to. Once all of the substrate is bound, the reaction will no longer speed up, since there will be nothing for additional enzymes to bind to.
What does it mean when a molecule is reduced (oxididized)
it means they lose elecrtrons
Two types of fermentation
lactic acid and alcoholic
location of krebs
matrix
why is eurkayotic larger than prokartoic
membrane bound organelles compartmentalize intracellular processes
endosymbiotic theory w/ supporting evidence
mitochondria and chloroplasts are derived from free living prokaryotes that were engulfed by another cell 1. have their own ribosomes and DNA 2. double membrane 3. control own reproduction 4. about same size as many prokaryotes
hypertonic
more solute outside of cell and less water on the inside. cell will shrivel. water moves out of cell
Endocytosis
movement of a substance by a vesicle to the inside of a cell
how is DNA/RNA synthesis directionally oriented?
new nucleotides are added to a 3' hydroxyl
which is not in a momoner of protein
nitrogenous base
cytoskeleton function
organizes the cell's structures and activities, anchoring many organelles -network of fibers extending throughout cytoplasm -composed of micotubules, microfilaments, intermediate filamets -interacts w/ other proteins to produce motility -helps support cell and maintain shape
cell wall
outer layer that maintains cell's shape and protects cell from mechanical damage; made of cellulose, other polysaccharides, and protein.
why is water considered polar
polar covalent bond in structure
Why does the stomata close?
prevent water loss
Four structural levels of proteins
primary structure:unique sequence of amino acids.amino acid sequence determined by gene (DNA).slight change in amino acid sequence can affect protein's structure and its function secondary structure: conformation of polypeptide backbone. localized folding or pleating of parts of the protein chain-result of H bonds between repeating structures of polypeptide-weak bonds-α helix and β pleated sheets tertiary structure: complete 3D conformation of polypeptide including backbone atoms and all its side chains. whole molecule folding-interactions between distant amino acids. hydrophobic interactions. cytoplasm is water-based. nonpolar amino acids cluster away from water. H bonds and ionic bonds-disulfide bridges. covalent bonds between sulfurs in sulfhydryls (S-H) quaternary structure: more than one polypeptide chain bonded together. only then does polypeptide become functional protein. hydrophobic interactions
The age of Earth and when prokaryotic and eukaryotic life emerged
prokaryotes: 3.5 billion years ago - stromatolites single cell eukaryotes: 2 billion years ago multicell eukaryotes: 1.5 billion years ago
Steps of Mitosis
prophase, metaphase, anaphase, telophase
which iwll bind to membrane protein (and not enter cell)
protein hormone
whihc macromoleces have sulfur
proteins
Three types of subatomic particles
protons, neutrons, electrons
proton pump
pumps (H+ ions) out of the cell, creating a proton gradient, protons then diffuse back into the cell, this is used to power the production of ATP
Glycolysis leads to the production of ____________ and two molecules of ATP. In the absence of oxygen, fermentation leads to the production of ______________. Glycolysis plus the citric acid cycle can convert the carbons of glucose to _________ , storing the energy as ATP, _____________ and ___________.
pyruvate, lactic acid, CO2, NADH, FADH2
Metabolism Problem Set Problem 2:Products of Glycolysis At the end of glycolysis, each molecule of glucose has yielded 2 molecules of _______, 2 molecules of ________, and a net of 2 molecules of _________
pyruvate; NADH; ATP
Calvin Cycle
reactions of photosynthesis in which energy from ATP and NADPH is used to build high-energy compounds such as sugars -uses ATP, NADPH, and CO2 and produced cabrohydrates -makes organic products that plants need using the products from the LR of photosynthesis -plants and other organisms mainly get CO2 from envinroment
intracellular receptors
receptors located inside the cell rather than on its cell membrane
active transport and its types
requires energy to move molecules from LOW to HIGH concentration endocytosis and exocytosis. moves AGAINST gradient- goes UP. uses atp. allow cells to accumulate material in greater concentration then are available
dif between smooth and orug er
rough RE compartamentalizes cell; smooth ER functions in detox and lipid synthesis
Prokaryotic cell structure
see diagram
what can enter cell through phospholipd bilayer
small, nonpolar molecuels: CO2, O2, steroids, nitrogen
Hypotonic
solute concentration is higher inside cell. outside has less solute and more water. soln will swell until burst. preferresed soln of plant cells. water moves into the cell
isotonic
solution concentration is the same inside and outside of cell. preferred of ant animal. no net water movement.
What cellular compartment becomes acidic (high concentration of hydrogen ions) during mitochondrial electron transport?
space between inner and outer mitochondrial membranes Electron transport produces a high concentration of H+ (protons) in the inner membrane space of the mitochondria.
what passes easily through membrane
steroid hormonee
CAM plants
store the organic acids made at night in vacuoles and use them for photosynthesis during the day when stomata are closed A plant that uses crassulacean acid metabolism, an adaptation for photosynthesis in arid conditions. In this process, carbon dioxide entering open stomata during the night is converted to organic acids, which release CO2 for the Calvin cycle during the day, when stomata are closed.
how are DNA and RNA dif?
sugar, nitrogenous base, stands
what is main input source of energy for all living organisms? where does energy go?
sunlight; during every energy transformation process, some energy is unusable, often lost as heat.
How electrochemical gradients and proton gradients are formed and function in cells
the electrical and concentration gradients of a membrane tend to drive sodium into and potassium out of the cell, and active transport works against these gradients. To move substances against a concentration or electrochemical gradient, the cell must utilize energy in the form of ATP during active transport.- the ion's concentration gradient and electrical force-drives diffusion of ions across the membrane the proton gradient may be used as an intermediate energy source for heat and flagellar rotation. It results from the higher concentration of protons outside the inner membrane of the mitochondria than inside the membrane, and becomes the driving force behind atp synthesis/hydrolysis.
Substrate Concentration on Enzyme Activity
• Increasing the concentration of substrate increases the rate of reaction (True up to a saturation point). • Collisions are more likely so more E-S complexes form. • The concentration will decrease over time therefore the rate of reaction will also decrease. • Therefore, the initial rate is the highest.
Aquaporins
water channel proteins that allow water to pass through cell membranes. facilitated diffusion
how stomata open
water comes in and causes an increase in turgor pressure. guard cell because turgid. stoma s OPEN
transpiration-adhesion-cohesion-tension mechanism o
water evaporating through the stomata produces a tension, or negative pressure, that pulls the water column up the plant. This column is maintained by the hydrogen bonding between water molecules (cohesion) and the hydrogen bonding between water molecules and the molecules that make up the cell walls (adhesion).
characteristics of the early planet and its atmosphere
weaker sun, thicker atmosphere, red brown color
