Biology - Diffusion&Osmosis_ch 5, How Osmosis Works Video and Quiz, CH 5.4-10, Bio210 Exam 2 (Ch5), BIOL Chapter 5 Review, Chapter 5 Membrane Questions, BIO EXAM 2, BIO201 Connect 4, Biology chapter 5
When studying with a friend for a test, what key points about osmosis would you make sure you tell them? Check all that apply.
*Osmosis refers to the movement of water along a concentration gradient. *If osmosis occurs across a membrane, then diffusion is not occurring.
The plasma membrane Ca²⁺-ATPase is a pump that functions in the primary active transport of Ca²⁺ out of the cell. What features do you expect of this pump and the cellular environment? Choose all that apply.
- It is an antiporter - It transports Ca²⁺ down its concentration gradient
Describe the main components of a biological membrane by filling in the missing terms.
- Small amphipathic phospholipids are the most abundant molecules in a membrane. - Larger proteins make up half of the mass of a membrane. - Polar carbohydrates are typically found attached to the outside of a membrane.
Calculate the Free Energy Change That Occurs as a Result of a Chemical Reaction Calculate the free energy change (ΔG) for a reaction A longrightarrow P if A has a free energy of 2.7 kcal/mol and P has a free energy of 2.2 kcal/mol.
.5 kcal/mol Part 2 Is this reaction endergonic or exergonic? endergonic
Arrange the electron acceptors in order from highest to lowest energy. 1 = Cytochrome c 2 = Oxygen 3 = Cytochrome c oxidase
1, 3, 2
Indicate if the following statements about membrane proteins are true or false. 1. They can aid in the transportation of molecules across membranes. 2. They are used in DNA replication. 3. They can act as cell surface receptors. 4. They are totally water soluble. 5. They can be enzymes.
1. True 2. False 3. True 4. False 5. True
Describe the main components of a biological membrane by filling in the missing terms. Small amphipathic ______(1)______ are the most abundant molecules in a membrane. Larger ______(2)______ make up half of the mass of a membrane. Polar ______(3)______ are typically found attached to the outside of a membrane.
1. phospholipids 2. proteins 3. carbohydrates
How many ATP molecules are needed to transport 36 Na+ and 24 K+ across the membrane?
12
The initial reaction of the citric acid cycle, also called the Krebs cycle, involves the addition of a
2-carbon molecule to a 4-carbon molecule.
Seven ATP molecules can theoretically cause how many Na+ and K+ to move across the membrane?
21 Na+ out and 14 K+ in
Aerobic respiration produces _______ molecules whereas anaerobic respiration produces ______ molecules.
34-38 ATP, 2 ATP
A single Na⁺/K⁺ ATPase pump is present in the plasma membrane of an artificial cell with an initial cellular environment of 500 molecules of Na⁺ and 1000 molecules of ATP inside the cell, 500 molecules of K⁺ outside the cell, and a net charge differential across the plasma membrane of 0. Assuming the only changes in the cellular environment are a result of the pump's actions, what would be the number of Na⁺, K⁺ and ATP molecules inside the cell after 10 cycles of the pump and what would be the net charge differential (inside - outside) across the plasma membrane?
470 Na⁺; 20 K⁺; 990 ATP and -20 charge differential (inside - outside)
Be able to read and understand the wave length diagram.
:D
Know the C4 and CAM plants
:D
Know the light reaction and the calvin cycle
:D
Know the stages of the calvin cycle
:D
Know the structure of chloroplasts
:D
Consider the biochemical pathway below, where A, B, and C are substrates and products and E1 and E2 are the enzymes that catalyze the reactions. If Enzyme 1 (E1) is inactive, which of the following compounds will accumulate? A--E1-->B--E2-->C
A only
NAD+ is made from niacin, a B vitamin. Based on the animation, if someone is deficient in niacin, which of the following symptoms might they experience?
A reduction in energy
what is the overall equation for photosynthesis? A) 6 CO2 + 12 H2O + Light energy → C6H12O6 + 6 O2 + 6 H2O B) 6 CO2 + 12 H2O + Light energy → C6H12O6 + 6 O2 C) 6 CO2 + Light energy → C6H12O6 + 6 O2 + 6 H2O D) 12 H2O + Light energy → C6H12O6 + 6 O2 + 6 CO2 + 6 H2O E) C6H12O6 + 6 O2 + 12 H2O + Light energy → 6 CO2 + 12 H2O
A) 6 CO2 + 12 H2O + Light energy → C6H12O6 + 6 O2 + 6 H2O
what are the final by-products of glucose oxidation during aerobic cell respiration? A) ATP, heat, and CO2 B) ATP only C) carbon dioxide only D) both ATP and heat only E) heat only
A) ATP, heat, and CO2
the oxidation of NADH in the formation of more ATP molecules compared to the oxidation of FADH2 because A) NADH enters the electron transport chain at an earlier point than FADH2. B) the electrons from NADH contain more energy than electrons from FADH2. C) FADH2 contributes fewer electrons to the electron transport chain. D) FADH2 isn't produced until a later stage in the citric acid cycle.
A) NADH enters the electron transport chain at an earlier point than FADH2
the purpose of the light reaction is to produce A) NADPH and ATP B) ATP and oxygen C) carbon dioxide and ATP D) glucose and NADPH E) oxygen and glucose
A) NADPH and ATP
Indicate the examples below that illustrate the first law of thermodynamics A) A plant uses sunlight to form a H+ gradient. B) A H+ gradient is used to produce ATP. C) 10% of the energy in one trophic level can be passed to the next trophic level. D) An animal uses ATP to move its muscles. E) An animal produces heat in the process of metabolism.
A) a plant uses sunlight to form a H+ gradient B) a H+ gradient is used to produce ATP D) an animal uses ATP to move its muscles
Match the descriptions with the correct membrane component Protein: A) can anchor to the cytoskeleton inside the cell B) can be attached to the surface of a membrane C) can span both leaflets of a membrane D) only spans one leaflet of the membrane E) small and amphipathic
A) can anchor to the cytoskeleton inside the cell B) can be attached to the surface of a membrane C) can span both leaflets of a membrane
A person working in your lab creates a synthetic semi-fluid like substance embedded with proteins that transport nutrients and ions. This leads you to believe the substance is most similar to A) cell membranes B) smooth ER C) rough ER D) cytoplasm E) mitochondrial matrix
A) cell membranes
the conversion of pyruvate to acetyl CoA is irreversible. Predict what would happen to fatty acids as a result of this A) Fatty acids cannot be converted into carbohydrates. B) Fatty acids cannot be metabolized in the citric acid cycle. C) Fatty acids can be metabolized in glycolysis. D) Fatty acids can be converted into carbohydrates.
A) fatty acids cannot be converted into carbohydrates
The best way to describe cellular membranes is A) fluid with lipid rafts B) solely composed of lipids C) composted of a single layer of amphipathic molecules D) selective to the transport of gases and small molecules only E) found in eukaryotes, but not in prokaryotes
A) fluid with lipid rafts
for heart muscles to beat in a coordinated rhythm ions must move from one cell to the next through _______ A) gap junctions B) desmosomes C) hemidesmosomes D) focal adhesions E) adherent junctions
A) gap junctions
you inject dye into a cell and observe that it moves into adjacent cells. This would occur through _______ A) gap junctions B) plasmodesmata C) adhering junctions D) tight junctions E) desmosomes
A) gap junctions
Which of the following is the correct formula for aerobic cellular respiration? A) glucose + 6 O2 → 6 CO2 + 6 H2O + energy intermediates + heat B) glucose + 6 O2 + 6 CO2 → 6 H2O + energy intermediates + heat C) glucose + 6 CO2 → 6 O2 + 6 H2O + energy intermediates + heat D) glucose + 6 O2 + heat → 6 CO2 + 6 H2O + energy intermediates E) glucose + 6 O2 + 6 H2O→ 6 CO2 + energy intermediates + heat
A) glucose + 6 O2 --> 6CO2 + 6 H2O + energy intermediates + heat
what processes will occur in the presence or absence of oxygen? A) glycolysis B) citric acid cycle C) oxidative phosphorylation D) cellular respiration E) electron transport chain
A) glycolysis
The plasma membrane Na+/K+-ATPase pump A) is used to generate sodium and potassium gradients across the membrane. B) is a symporter. C) is a pump for active transport of K+ out of the cell and Na+ into the cell. D) is a pump for facilitated diffusion of K+ into the cell and Na+ out of the cell. E) does not require ATP.
A) is used to generate sodium and potassium gradients across the membrane
What would happen to a plant that is treated with a chemical that prevents electrons from moving through the electron transport chain? A) It could not generate an electrochemical H+ gradient across a membrane. B) It could not produce NADP+. C) Water would be broken down to form oxygen at a higher rate to compensate. D) It could no longer produce CO2. E) More electrons would be available for the light harvesting array.
A) it could not generate an electrochemical H+ gradient across a membrane
The equation, 6CO2 + 6H2O →C6H12O6 + 6O2, describes which process? A) photosynthesis B) nitrogen fixation C) light reaction D) aerobic respiration E) Calvin cycle
A) photosynthesis
Administration of digoxin is not the only way to treat atrial fibrillation. From the list below, select all other plausible strategies to increase intracellular calcium concentrations. A)Administer a different inhibitor of the Na+/Ca2+ antiporter B)Administer an inhibitor of the Ca2+-ATPase pump, which removes Ca2+ from the cytosol C)Administer calcium chelators to reduce the extracellular Ca2+ concentration D)Administer calcium chloride to raise the extracellular Ca2+ concentration
A)Administer a different inhibitor of the Na+/Ca2+ antiporter B)Administer an inhibitor of the Ca2+-ATPase pump, which removes Ca2+ from the cytosol D)Administer calcium chloride to raise the extracellular Ca2+ concentration
N-linked protein glycosylation Which of the following is true of N-linked protein glycosylation? A)The carbohydrates are first attached to the lipid dolichol. B)It occurs entirely in the Golgi apparatus. C)It occurs primarily on proteins that are not secreted out of the cell. D)The carbohydrates are attached directly to the protein.
A)The carbohydrates are first attached to the lipid dolicho
Analyze a Defective Na+/K+ ATPase A defective Na+/K+ ATPase pump is isolated from a plasma membrane and studied. Careful measurements in the laboratory determine that the pump is able to hydrolyze ATP and transports 3 Na+ ions across the plasma membrane. The pump is also able to bind 2 K+ ions with high affinity. However, the pump is unable to shuttle K+ ions across the plasma membrane. Based on these observations, what is the most likely cause of the defect in this pump? A)The defective pump is unable to release phosphate B)The defective pump is locked into a rigid conformation and is unable to undergo conformational changes C)The defective pump is unable to release Na+ ions D)The defective pump is unable to bind K+ ions E)The defective pump is unable to bind ATP
A)The defective pump is unable to release phosphate
Describe the Na+/K+ ATPase Pump A)The sodium-potassium pump functions to pump sodium ions out of the cell and potassium ions into the cell. B)sodium ions into the cell and potassium ions out of the cell. C)sodium and potassium ions into the cell. D)sodium and potassium ions out of the cell. E)sodium and potassium ions in both directions across the cell membrane.
A)The sodium-potassium pump functions to pump sodium ions out of the cell and potassium ions into the cell.
Energy Source for Na+/K+ Pump What is the source of energy used to power the sodium-potassium pump? A)hydrolysis of ATP B)formation of ATP C)binding of ATP D)release of phosphate E)diffusion of Na+ down its gradient
A)hydrolysis of ATP
Small amphipathic___________ are the most abundant molecules in a membrane. A)phospholipids B)Nucleci acids C) Carbohydrates D) proteins
A)phospholipids
Membrane Permeability and Facilitated Diffusion Which of the following molecules are most likely to pass through the membrane by facilitated diffusion? A)urea and sucrose. B)H2O and O2. C)CO2 and O2. D)CO2 and H2O.
A)urea and sucrose.
The rate of diffusion is affected by temperature, size of molecule, and size of the concentration gradient. Use this information to determine which system in the following examples will have a higher initial rate of diffusion. A. 0.2 mL of 2 mM sodium chloride added to 1.0 L water vs. 0.2 mL of 2 M sodium chloride added to 1.0 L water B. 0.2 mL of a 2 mM solution of the enzyme carbonic anhydrase added to 1.0 L water vs. 0.2 mL of 2 mM sodium chloride added to 1.0 L water C. A cube of sugar in hot coffee vs. a cube of sugar in room temperature coffee
A. 2 M sodium chloride B. sodium chloride C. hot coffee
Sucrose concentration is higher in the cytoplasm than in the extracellular environment. Na+ concentration is higher in the extracellular environment than in the cytoplasm. Animal cells can take up sucrose against its concentration gradient using a Na+/sucrose symporter. Indicate if the following statements are true or false. A. In the Na+/sucrose symporter, Na+ is also moving against its concentration gradient. B. For the symporter to work, the cell must first establish a Na+ concentration gradient. C. A symporter works by making the phospholipid bilayer more permeable to ions and sucrose. D. Moving sucrose against its concentration gradient is a form of active transport. E. A Na+/sucrose antiporter would be capable of moving sucrose into the cell while moving Na+ out of the cell. F. Since the Na+/sucrose symporter exchanges a single sucrose for a single Na+, it can also be considered a uniporter.
A. False B. True C. False D. True E. False F. False
The Energetics of Coupled Transport Sucrose concentration is higher in the cytoplasm than in the extracellular environment. Na+ concentration is higher in the extracellular environment than in the cytoplasm. Animal cells can take up sucrose against its concentration gradient using a Na+/sucrose symporter. Indicate if the following statements are true or false. A. In the Na+/sucrose symporter, Na+ is also moving against its concentration gradient. B. For the symporter to work, the cell must first establish a Na+ concentration gradient. C. A symporter works by making the phospholipid bilayer more permeable to ions and sucrose. D. Moving sucrose against its concentration gradient is a form of active transport. E. A Na+/sucrose antiporter would be capable of moving sucrose into the cell while moving Na+ out of the cell. F. Since the Na+/sucrose symporter exchanges a single sucrose for a single Na+, it can also be considered a uniporter
A. In the Na+/sucrose symporter, Na+ is also moving against its concentration gradient.FALSE B. For the symporter to work, the cell must first establish a Na+ concentration gradient. TRUE C. A symporter works by making the phospholipid bilayer more permeable to ions and sucrose. FALSE D. Moving sucrose against its concentration gradient is a form of active transport. TRUE E. A Na+/sucrose antiporter would be capable of moving sucrose into the cell while moving Na+ out of the cell. FALSE F. Since the Na+/sucrose symporter exchanges a single sucrose for a single Na+, it can also be considered a uniporter. FALSE
Mammals like caribou that live in the arctic often have different lipids in the cells of their legs compared to the cells of their internal organs. Their legs get colder than their internal organs, which stay warmer. Indicate true or false which of the following adaptations you would expect to find in the lipids found in the cells of the legs of a caribou? A. The lipids would be more saturated. B. The fatty acyl tails of the phospholipids would be shorter. C. The membranes would contain more cholesterol
A. The lipids would be more saturated. FALSE B. The fatty acyl tails of the phospholipids would be shorter. TRUE C. The membranes would contain more cholesterol. TRUE
Membrane proteins Indicate if the following statements about membrane proteins are true or false. A. They can aid in the transportation of molecules across membranes. B. They are used in DNA replication. C. They can act as cell surface receptors. D. They are totally water soluble. E. They can be enzymes
A. They can aid in the transportation of molecules across membranes. TRUE B. They are used in DNA replication. FALSE C. They can act as cell surface receptors. TRUE D. They are totally water soluble. fFALSE E. They can be enzymes. TRUE
Indicate if the following statements about membrane proteins are true or false. A. They can aid in the transportation of molecules across membranes. B. They are used in DNA replication. C. They can act as cell surface receptors. D. They are totally water soluble. E. They can be enzymes.
A. True B. False C. True D. False E. True
30-34 ATP
ATP Synthase
Atrazine is an herbicide that competes with Q (plastoquinone) for the electrons that are released from Photosystem II after it is struck by light. Which of the following products of the light reaction would atrazine prevent from forming?
ATP and NADPH
The Calvin cycle uses ________, which are products of the light reactions of photosynthesis.
ATP and NADPH
Calculating Chemical and Electrochemical Gradients Established By the Na+/K+ ATPase Pump Calculating Chemical and Electrochemical Gradients Established By the Na+/K+ ATPase Pump
ATP consumed: 9378 Net molecules of Na+ transported: 28134 Net molecules of K+ transported: 18756 Net charge differential intracellular : extracellular: 9378
Calvin Cycle
ATP is consumed Reduction of carbon compounds Reduction of NADPH
Light Reaction
ATP is produced NADPH is a product Oxidation of water
If the inner mitochondrial membrane was freely permeable to protons (H+) what would be the most devastating result to the cell?
ATP would not be produced by oxidative phosphorylation.
Which best explains the role of plant pigments in photosynthesis?
Absorb light energy
DNP (dinitrophenol) makes the inner mitochondrial membrane permeable to H+ions. DNP blocks ATP synthesis by
Allowing H+ ions to cross the mitochondrial membrane without passing through ATP synthase.
When a cell receives a signal, various cellular responses can occur. Classify which type of response each group of proteins could regulate. Enzyme
Alter metabolism Associated with breakdown of molecules
The advantage of second messengers is best described as
Amplification of the signal
Patients with Parkinson's Disease have been shown to have a block in the movement of autophagosomes towards lysosomes. What would you predict as a result?
An accumulation of old or damaged mitochondria
What is the role of rubisco in the Calvin cycle?
As a catalyst to add CO2 onto RuBP.
a comparison of mitochondria and chloroplast shows that A) they have very different electron transport protein complexes. B) both generate ATP via a H+ electrochemical gradient. C) both use an increase in pH in their inner-membrane space to produce ATP. D) both use oxygen as a final electron acceptor. E) only mitochondria contain ATP synthase.
B) both generate ATP via a H+ electrochemical gradient
in which organelle of the plant does photosynthesis take place? A) grana B) chloroplast C) mitochondria D) thylakoid membrane E) mesophyll
B) chloroplast
A bowl of sugar water is very stable. However, cells can rapidly break down sugar into carbon dioxide and water. What is the best explanation for this observation? A) Breakdown of glucose has a negative delta G outside of cells, but a positive delta G inside cells. B) Enzymes in the cell catalyze the breakdown of glucose. C) Cells use energy to break down glucose. D) Living cells make the water warmer, speeding up the reaction. E) Glucose becomes more chemically reactive inside a cell. F) The water is activated by the presence of living cells.
B) enzymes in the cell catalyze the breakdown of glucose
The wood in a match is made up of cellulose, which is a polymer of glucose molecules. When you light the match, heat and light are given off, indicating that a/an A) potential energy reaction is occurring B) exergonic reaction is occurring C) equilibrium reaction is occurring D) kinetic energy reaction is occurring E) endergonic reaction is occurring
B) exergonic reaction is occurring
Following a meal, glucose must move from the gut lumen where there is a high glucose concentration into the intestinal cell where there is a relatively low level of glucose. This movement is called A) passive diffusion. B) facilitated diffusion. C) active transport. D) endocytosis. E) exocytosis.
B) facilitated diffusion
Your liver produces 90% of the cholesterol found in your body. When cholesterol levels get too high, the first enzyme in the pathway of cholesterol synthesis is inhibited. This is an example of A) denaturation B) feedback inhibition C) a coenzyme D) positive feedback E) equilibrium
B) feedback inhibition
in cellular respiration, carbon dioxide is formed from the oxidation of which of the following? A) cytochrome oxidase B) glucose C) water D) NADH E) oxygen
B) glucose
A green plant is first grown in blue light and then in green light. The likely outcome for photosynthesis in both phases is A) no plant growth in blue light and decreased plant growth in green light. B) increased plant growth in blue light and no plant growth in green light. C) no plant growth in blue light and increased plant growth in green light. D) decreased plant growth in blue light and no plant growth in green light.
B) increased plant growth in blue light and no plant growth in green light
You plant a seed in a pot and water it. A few days later you see small green leaves appear out of soil. You put a jar over the plant and monitor O2 and CO2 levels during the day and then again at night. Match the appropriate activities and levels of water, carbon dioxide, and oxygen over the course of a day. Oxygen: A) backbone of cellulose B) increases during the day C) leaves leaf through stomata D) decreases at night E) enters leaf through stomata F) reduced in the Calvin cycle G) source of electrons for photosynthesis H) oxidized in photosystem II I) decreases during the day J) increases at night
B) increases during the day D) decreases at night C) leaves leaf through stomata
Health Implications of Facilitated Diffusion GLUT1 is a glucose transporter that is responsible for the facilitated diffusion of glucose across the blood-brain barrier. GLUT1 deficiency syndrome is a rare genetic disorder where mutations in the gene encoding GLUT1 reduce or eliminate the function of the GLUT1 protein. Affected individuals suffer from seizures along with a number of potential neurological problems. What is the link between GLUT1 dysfunction and these neurological complications? A)diffusion of glucose from the brain to the blood B)sporadic and uncontrolled diffusion of glucose from the blood to the brain C)excessive and constant diffusion of glucose from the blood to the brain D)insufficient diffusion of glucose from the blood to the brain
B) insufficient diffusion of glucose from the blood to the brain
Passive diffusion A) is the process by which molecules move from an area of low concentration to an area of high concentration. B) is a spontaneous process. C) requires the presence of a transmembrane protein. D) will occur so long as the membrane is freely permeable to the solute. E) requires energy.
B) is a spontaneous process
How does an enzyme work to catalyze a reaction? A) it increases the concentration of the reactants in a reaction B) it lowers the activation energy of a reaction C) it raises the temperature of a reaction D) it supplies the energy to speed up a reaction E) it allows the reaction to proceed through different intermediates
B) it lowers the activation energy of a reaction
The answer that best describes the composition of a cell's membrane is A) a wall with doors that allow proteins through B) lipid rafts floating and drifting in a constantly moving sea C) a net with holes that allow molecules through D) a two-layered cake that has a fatty covering the repels water
B) lipid rafts floating and drifting in a constantly moving sea
place the statements in the appropriate pathway Cellular respiration: A) produces organic molecules B) produces CO2 C) consumes glucose D) converts H2O to O2 E) found only in photoautotrophs E) takes in CO2 F) O2 exits as H2O
B) produces CO2 F) O2 exits as H2O C) consumes glucose
The process that forms the electrochemical gradient during photosynthesis is the A) hydrolysis of ATP. B) pumping of H+ into the thylakoid lumen. C) production of H+ in the stroma during NADPH production. D) movement of water by osmosis. E) production of water from oxygen in the thylakoid lumen.
B) pumping of H+ into the thylakoid lumen
During glycolysis, glucose is broken down into A) ATP B) pyruvate C) NADH D) acetyl CoA E) oxygen
B) pyruvate
in the Calvin cycle, CO2 binds to A) water B) ribulose biphosphate C) photosystem II D) glucose E) NADPH
B) ribulose biphosphate
Sodium concentrations are higher outside and glucose concentrations are higher inside the cell. Using the same membrane protein for Na+ and glucose transport, what is it called when a Na+ electrochemical gradient is used to drive glucose transport into the cell against its concentration gradient? A) Primary active transport B) Secondary active transport C) Primary facilitated diffusion D) Secondary facilitated diffusion E) Passive diffusion
B) secondary active transport
the main structure for gas exchange in plants is called the A) chloroplast B) stomata C) mesophyll D) epidermis E) root
B) stomata
describe the advantage of having a pathway organized as a cycle A) All pathways are organized as a cycle. B) The final product of the cycle can be combined with a small molecule entering the cycle, making it more reactive. C) The cycle can continue without any regulation being necessary. D) A cycle produces energy which keeps it moving.
B) the final product of the cycle can be combined with a small molecule entering the cycle, making it more reactive
Digoxin is an inhibitor of Na+/K+ ATPase that is used to treat irregular heartbeats (medical term: atrial fibrillation). Digoxin slows the heartbeat by raising intracellular calcium levels. What is the most reasonable explanation for how digoxin can raise intracellular calcium concentrations through inhibiting Na+/K+ ATPase? A)Na+/K+ ATPase acts to shuttle Ca2+ out of the cell. Digoxin inhibits Na+/K+ ATPase, preventing it from shuttling Ca2+ out of the cell. As a result, intracellular Ca2+ levels increase. B)Inhibiting Na+/K+ ATPase results in a lower than normal intracellular Na+ concentration. This reduces the effectiveness of the Na+/Ca2+ antiporter. As a result, intracellular Ca2+ levels increase. C)Inhibiting Na+/K+ ATPase results in a higher than normal intracellular Na+ concentration. This reduces the effectiveness of the Na+/Ca2+ antiporter. As a result, intracellular Ca2+ levels increase. D)Inhibiting Na+/K+ ATPase results in a lower than normal extracellular K+ concentration. This increases the effectiveness of a K+/Ca2+ symporter that drives the influx of both K+ and Ca2+. As a result, intracellular Ca2+ levels increase.
B)Inhibiting Na+/K+ ATPase results in a lower than normal intracellular Na+ concentration. This reduces the effectiveness of the Na+/Ca2+ antiporter. As a result, intracellular Ca2+ levels increase.
Compensating for Disfunction in Facilitated Diffusion GLUT1 deficiency syndrome is a rare genetic disorder where mutations in the gene encoding GLUT1 reduce or eliminate the function of the GLUT1 protein. Affected individuals suffer from seizures along with a number of potential neurological problems. What would be the most effective therapy to treat patients suffering from this disorder? A)Treat with drugs that will elevate ATP levels in the blood-brain barrier and promote the active transport of glucose by GLUT1 B)Switch to a diet containing carbohydrates other than glucose to circumvent the deficient transport C)Switch to a high glucose diet to overcome the deficient transport D)Regularly inject GLUT1 into the patient's blood to serve as a replacement for the deficient transporter
B)Switch to a diet containing carbohydrates other than glucose to circumvent the deficient transport
Requirements of Facilitated Diffusion Facilitated diffusion requires A)enzymes. B)carrier proteins. C)lipid carriers. D)carbohydrate carriers. E)lipid or carbohydrate carriers.
B)carrier proteins
Which of the following is the most direct source of energy for cotransport? A)the movement of one of the transported substances up its concentration gradient B)the movement of one of the transported substances down its concentration gradient C)ATP hydrolysis D)ATP formation E)cotransport requires no energy
B)the movement of one of the transported substances down its concentration gradient
An experiment involves 4 beakers of fluid containing bags with different solutions. Beaker 1 contains a 0.2M solution with a 0.2M solution bag. Beaker 2 has a 0.2M solution with a 1M solution bag. Beaker 3 holds a 0.2M solution with a 0.4M solution bag. Beaker 4 contains a 0.2M solution with a 0.1M solution bag. Predict which beaker will contain a bag with the largest change in mass after 30 minutes.
Beaker 2 - has a 0.2M solution with a 1M solution bag
No ATP
Breakdown of pyruvate Complexes I-IV of the electron transport chain
Use image 11 In the example above, how does the final product of the pathway inhibit the pathway?
By binding to an allosteric site of the first enzyme in the pathway.
How do electrons enter the electron transport chain?
By the oxidation of NADH
How many net ATP and NADH molecules are produced from one molecule of glucose during glycolysis? A) 0 ATP, 6 NADH B) 3 ATP, 4 NADH C) 2 ATP, 2 NADH D) 2 ATP, 6 NADH E) 4 ATP, 2 NADH
C) 2 ATP, 2 NADH
Calculated the Charge Differential after Multiple Pump Cycles A single Na+/K+ ATPase pump is present in the plasma membrane of an artificial cell with an initial cellular environment of 500 molecules of Na+ and 1000 molecules of ATP inside the cell, 500 molecules of K+ outside the cell, and a net charge differential across the plasma membrane of 0. Assuming the only changes in the cellular environment are a result of the pump's actions, what would be the number of Na+, K+ and ATP molecules inside the cell after 10 cycles of the pump and what would be the net charge differential (inside - outside) across the plasma membrane? A)30 Na+; 20 K+; 900 ATP and -10 charge differential (inside - outside) B)30 Na+; 480 K+; 10 ATP and +20 charge differential (inside - outside) C)470 Na+; 20 K+; 990 ATP and -20 charge differential (inside - outside) D)300 Na+; 200 K+; 100 ATP and -100 charge differential (inside - outside) E)470 Na+; 480 K+; 10 ATP and +100 charge differential (inside - outside)
C) 470 Na+; 20 K+; 990 ATP and -20 charge differential (inside - outside)
Evaluate the Relative Impact of Na+/K+ ATPase Disfunction Which of the following dysfunctions in the Na+/K+ ATPase will have the most dramatic effect on the establishment of a concentration gradient? A)A reduction in the ability of ATP to bind to the pump B)A decrease in the Na+ binding affinity for the phosphate-bound form C)A reduction in the rate of ATP hydrolysis D)An increase in the K+ binding affinity in the phosphate-bound form
C) A reduction in the rate of ATP hydrolysis
Polar_____are typically found attached to the outside of a membrane. A)phospholipids B)Nucleci acids C) Carbohydrates D) proteins
C) Carbohydrates
identify a reactant in the light reaction of photosynthesis A) ATP B) oxygen C) H2O D) carbon dioxide E) NADPH
C) H2O
Receptor Mediated Endocytosis Lipoproteins like LDL and HDL transport lipids and proteins through the blood stream. Receptors on cells can bind to the lipoproteins and remove them from the blood, using the lipids for energy and to produce membranes. Which of the following mechanisms would be used to move a lipoprotein into a cell? A)Active transport B)Facilitated diffusion C)Receptor-mediated endocytosis D)Endocytosis E)Exocytosis
C) Receptor-mediated endocytosis
_____ bind two or more ions or molecules and transport them in opposite directions across a membrane A) Uniporters B) Symporters C) Antiporters D) Dual transporters E) Channel pumps
C) antiporters
Your body needs amino acids to build new proteins encoded by your genes. Many of these amino acids come from your diet through the ____ of proteins you eat. A) anabolism B) phosphorylation C) catabolism D) biosynthesis
C) catabolism
where does glycolysis take place? A) mitochondrial inner membrane B) mitochondrial intermembrane space C) cytosol D) mitochondrial membrane E) mitochondrial matrix
C) cytosol
energy released by the electron transport chain is used to pump H+ ions into which location? A) mitochondrial inner membrane B) cytosol C) mitochondrial intermembrane space D) mitochondrial matrix E) mitochondrial outer membrane
C) mitochondrial intermembrane space
cellular respiration produces the most energy in the form of ATP from A) substrate-level phosphorylation B) the citric acid cycle C) oxidative phosphorylation D) the production of lactate E) glycolysis
C) oxidative phosphorylation
the ultimate source of energy for reactions in a plant is A) catabolism B) plants C) the sun D) glucose E) glycogen
C) the sun
the energy for producing organic molecules in plants is directly driven by A) the use of rubisco to collect energy from ATP made during the light reactions. B) the use of chlorophyll to transfer electrons from photons to other pigments. C) the use of light to provide electrons for oxidation and reduction reactions. D) the use of NADPH to carry photons to the Calvin cycle. E) the use of water to transfer the energy of hydrolysis to enzymes.
C) the use of light to provide electrons for oxidation and reduction reactions
If contents of the intestines can leak into the blood then _______ must have been damaged A) desmosomes B) focal adhesions C) tight junctions D) gap junctions E) hemidesmosomes
C) tight junctions
A drug company wants to design a medicine that will bind to surface proteins and initiate a conformational change allowing the drug to enter. You suggest the study focus on A) receptors B) channels C) transporters D) pumps
C) transporters
Aquaporin allows water molecules to move very rapidly across a plasma membrane. What would be the best definition of this process? A)Facilitated diffusion using a transporter B)Active transport using a transporter C)Facilitated diffusion using a channel D)Active transport using a channel
C)Facilitated diffusion using a channel
Pumps The plasma membrane Ca2+-ATPase is a pump that functions in the primary active transport of Ca2+ out of the cell. What features do you expect of this pump and the cellular environment? Choose all that apply. A)It transports Na+ and K+ ions B)It is an antiporter C)The extracellular Ca2+ concentration is higher than the intracellular Ca2+ concentration D)It hydrolyzes ATP E)It is capable of undergoing a conformational change F)The affinity for Ca2+ is low when the enzyme is bound to phosphate G)It transports Ca2+ down its concentration gradient
C)The extracellular Ca2+ concentration is higher than the intracellular Ca2+ concentration D)It hydrolyzes ATP E)It is capable of undergoing a conformational change F)The affinity for Ca2+ is low when the enzyme is bound to phosphate
During fermentation, yeast break down pyruvate into ______ and acetaldehyde.
CO₂
Which of the following statements is FALSE?
Ca2+ and cAMP are both protein kinases that will proliferate a phosphorylation cascade.
A mutation has occurred, disabling Ca2+ channels in the endoplasmic reticulum so that they can no longer open. The action of which molecule will this mutation this most affect?
Calmodulin
Autotrophs use the ___________ to make organic molecules.
Calvin Cycle
ATP and NADPH drive the _______
Calvin cycle
autotrophs use the _____ to make organic molecules
Calvin cycle
ATP and NADPH drive the __________
Calvin cycle.
Match the properties described with one of the four components of a membrane. Transmembrane protein
Can span both layers of a membrane. Can form channels to allow small molecules to cross membranes.
A cell using protein-mediated facilitated diffusion is treated with a toxin that prevents conformation change in the membrane protein. What is the most likely outcome?
Carrier protein dysfunction will increase the gradient.
Facilitated Diffusion
Cell by diffusion through specific channel proteins or carrier protein embedded in the plasma membrane, provided there is a higher concentration of the moelcule outside the cell than inside
Epinephrine inhibits salivary gland activity and muscle cell contraction in the airways, yet stimulates glycogen release in muscle cells and heart muscle cell contraction. How could one hormone have opposing effects on different organs?
Cells in the different tissues would have epinephrine receptors coupled to different signaling pathways.
The sodium channel is formed by a channel protein. Which of the following statements about channel proteins is TRUE?
Channel proteins can be opened or closed by cell signaling molecules.
How many ATP and NADH molecules are produced from each molecule of glucose in the citric acid cycle only? A) 0 ATP, 6 NADH B) 3 ATP, 4 NADH C) 4 ATP, 2 NADH D) 2 ATP, 6 NADH E) 1 ATP, 2 NADH
D) 2 ATP, 6 NADH
What is produced during the citric acid cycle? A) pyruvate, ATP, and NADH B) oxygen C) ATP and NAD+ D) ATP, NADH, and FADH2 E) a proton gradient
D) ATP, NADH, and FADH2
the products of photosynthesis are A) ATP and NADPH B) sunlight and plants C) CO2 and H2O D) O2 and carbohydrates E) CO2 and energy
D) O2 and carbohydrates
Which is true of the fluid mosaic model of membrane structure? A) Membranes behave more like a solid than a liquid. B) Lipids can flip from one leaflet to another as easily as they can move laterally in a membrane. C) Proteins can easily move across membranes. D) Proteins can easily move laterally through membranes.
D) Proteins can easily move laterally through membranes.
the process of breaking glycogen down to glucose is an example of A) dehydration B) metabolism C) catalysis D) catabolism E) anabolism
D) catabolism
The equation, C6H12O6 + 6O2 →6CO2 + 6H2O (ATP + heat), describes what process? A) anaerobic metabolism B) glycolysis C) cell fermentation D) cell respiration E) photosynthesis
D) cell respiration
in the citric acid cycle, the acetyl group is removed from acetyl CoA and attached to oxaloacetate to form A) succinate B) oxaloacetate C) fumarate D) citrate E) malate
D) citrate
the electron transport chain in bacteria is located A) in the cytoplasm B) in the mitochondria C) in the cell wall D) in the cell membrane E) in the plasmid
D) in the cell membrane
Match the descriptions with eh correct membrane component Phospholipid: A) can anchor to the cytoskeleton inside the cell B) can be attached to the surface of a membrane C) can span both leaflets of a membrane D) only spans one leaflet of the membrane E) small and amphipathic
D) only spans one leaflet of the membrane E) small and amphipathic
the light reactions synthesize ATP, NADPH, and O2 using which of the following processes A) reduction only B) neither oxidation, reduction, nor electrolysis C) oxidation only D) oxidation and reduction E) oxidation, reduction, and electrolysis
D) oxidation and reduction
When pyruvate is converted to acetyl CoA it is _______ A) reduced B) phosphorylated C) anabolized D) oxidized
D) oxidized
water held behind a dam would best reflect A) chemical energy B) kinetic energy C) heat energy D) potential energy E) mechanical energy
D) potential energy
a plant performing photosynthesis will A) produce oxygen and consume water. B) produce carbon dioxide and consume oxygen. C) produce carbon dioxide and consume water. D) produce oxygen and consume carbon dioxide. E) produce water and consume carbon dioxide.
D) produce oxygen and consume carbon dioxide
Larger ____________ make up half of the mass of a membrane. A)phospholipids B)Nucleci acids C) Carbohydrates D) proteins
D) proteins
If glycolysis was blocked in yeast, which of the following would decrease in concentration? A) oxygen B) ethanol C) NAD+ D) pyruvate E) carbon dioxide
D) pyruvate
The movement of sucrose and H+ into the cell by the same membrane protein reflects the actions of what type of transporter? A) Voltage-gated channel. B) Mechanosensitive channel. C) Uniporter. D) Symporter. E) Antiporter.
D) symporter
both ATP and NADPH are required for A) both the light reaction and Calvin cycle. B) the light reaction only. C) electron transport through the thylakoid membrane. D) the Calvin cycle only. E) neither the light reaction nor the Calvin cycle.
D) the Calvin cycle only
Which membrane component is most important for allowing large, charged molecules to pass through the membrane? A) peripheral proteins B) cholesterol C) glycosylated lipids D) transmembrane proteins E) carbohydrate channels
D) transmembrane proteins
If you wanted to install lights to grow plants indoors, the type of light would you want to use is A) infrared, because it has high energy wavelengths. B) gamma rays, because it has high energy wavelengths. C) microwaves, because it has low energy wavelengths. D) visible light, because it has low energy wavelengths E) ultraviolet, because it has high energy wavelengths.
D) visible light, because it has low energy wavelengths
Fluid mosaic model of membrane structure Which of the following is true of the fluid mosaic model of membrane structure? A)Membranes behave more like a solid than a liquid. B)Lipids can flip from one leaflet to another as easily as they can move laterally in a membrane. C)Proteins can easily move across membranes. D)Proteins can easily move laterally through membranes.
D)Proteins can easily move laterally through membranes.
A toxin that disrupted membrane antiport would prevent A)simultaneous movement of an amino acid and protons into the cell B)simultaneous movement of an amino acid and protons out of the cell C)coupling of the inward movement of water with the outward movement of protons D)coupling the outward movement of Ca2+ with the inward movement of Na+
D)coupling the outward movement of Ca2+ with the inward movement of Na+
Scientists and doctors are interested in using human stem cells cultured in the lab to produce a variety of tissues for transplants. To do this - for stem cells to become specialized blood, skin, muscle or nerve cells- they must go through which process?
Differentiation
Osmosis
Diffusion of water across a membrane toward a higher solute concentration
What makes a membrane more fluid?
Double bonds
A cell membrane is more permeable to K+ than Na+. What would happen if the membrane was more permeable to Na+ than to K+?
Due to the increased movement of Na+ inward, the membrane potential would become more positive.
In addition to ATP, what are the end products of glycolysis? A) CO2 and H2O B) CO2 and NADH C) CO2 and pyruvate D) H2O, NADH, and citrate E) NADH and pyruvate
E) NADH and pyruvate
which best explains the role of plant pigments in photosynthesis? A) produce photon energy B) convert heat to electricity C) reduce NADP D) provide electrons E) absorb light energy
E) absorb light energy
in photosynthesis, carbon dioxide gas is reduced and combined to form glucose. This is an example of A) exergonic B) catabolism C) hydrolysis D) metabolism E) anabolism
E) anabolism
If the tight junctions in the intestine were disrupted A) small molecules would not be able to move into cells lining the intestine. B) small molecules would not be exchanged between neighboring intestinal cells. C) intestinal cells could not attach to the extracellular matrix. D) intestinal cells could not attach to integral membrane proteins. E) bacteria could move from the intestines to the bloodstream causing an infection.
E) bacteria could move from the intestines to the bloodstream causing an infection
______ act as rivets anchoring adjacent cells together at spots throughout the cell A) hemidesmosomes B) fibronectin C) focal adhesions D) adherent junctions E) desmosomes
E) desmosomes
An autotroph captures energy from other sources and does not actually produce energy because A) the transfer of energy increases the disorder of a system. B) kinetic energy is based on location. C) the transfer of energy increases entropy. D) once energy is created it can be destroyed. E) energy cannot be created or destroyed.
E) energy cannot be created or destroyed
a logical consequence of the second law of thermodynamics could be stated A) energy can be transferred or transformed, but it cannot be created or destroyed. B) if there is an increase in the energy of a system, there must be a corresponding decrease in the energy of the rest of the universe. C) every energy transfer requires activation energy from the environment. D) if the entropy of a system increases, there must be a corresponding decrease in the entropy of the universe. E) every chemical reaction must increase the total entropy of the universe.
E) every chemical reaction must increase the total entropy of the universe
The hormone insulin is a protein produced in the pancreas and then secreted into the bloodstream after a meal to increase glucose uptake by tissues. Which mechanisms would be used to secrete insulin from the pancreas? A) active transport B) facilitated diffusion C) diffusion D) endocytosis E) exocytosis
E) exocytosis
A new flower species has a unique photosynthetic pigment. The leaves of this plant appear to be blue-green. What wavelengths of visible light does this pigment reflect? A) blue and violet B) green, red, and violet C) red and yellow D) red, yellow, and green E) green and blue
E) green and blue
What are two major components of cell membranes? A) glycolipids and phospholipids B) cholesterol and porteins C) phospholipids and carbohydrates D) phospholipids and cholesterol E) phospholipids and proteins
E) phospholipids and proteins
gap junctions in animal cells are most similar to ______ in plant cells A) middle lamella B) tight junctions C) primary cell walls D) hemidesmosomes E) plasmodesmata
E) plasmodesmata
the primary function of an enzyme or any biological catalyst is to A) increase the rate of a reaction. B) change the direction of a reaction. C) reduce the energy of activation of a reaction. D) increase the rate of a reaction and change the direction of a reaction. E) reduce the energy of activation and increase the rate of a reaction.
E) reduce the energy of activation and increase the rate of a reaction
In the reaction, 6CO2 + 6H2O →C6H12O6 + 6O2, carbon dioxide is being ____. A) condensed B) phosphorylated C) oxidized D) hydrolyzed E) reduced
E) reduced
place the statements in the appropriate pathway Photosynthesis: A) produces organic molecules B) produces CO2 C) consumes glucose D) converts H2O to O2 E) found only in photoautotrophs E) takes in CO2 F) O2 exits as H2O
E) takes in CO2 D) converts H2O to O2 A) produces organic molecules E) found only in photoautotrophs
The hormone insulin is a protein produced in the pancreas and then secreted into the blood stream after a meal to increase glucose uptake by tissues. Which of the following mechanisms would be used to secrete insulin from the pancreas? A)Active transport B)Facilitated diffusion C)Diffusion D)Endocytosis E)Exocytosis
E)Exocytosis
Secondary Active Transport of Sucrose Sugars can be transported into cells against their concentration gradient because of A)osmosis. B)simple diffusion. C)facilitated diffusion. D)antiport with Na+. E)symport with Na+.
E)symport with Na+.
Consider the biochemical pathways illustrated below. Product D will act as an allosteric inhibitor of what enzyme to regulate its own production? A--E1-->B--E2-->C--E3-->D B--E4-->E
E2
NAD+ is a coenzyme for many enzymes involved in redox reactions. This means that
Enzymes that use NAD+ as a coenzyme will not function properly if NAD+ is not available.
The hormone insulin is a protein produced in the pancreas and then secreted into the blood stream after a meal to increase glucose uptake by tissues. Which of the following mechanisms would be used to secrete insulin from the pancreas?
Exocytosis
Place the extracellular cell feature with the appropriate cell type. Animal Cell
Extracellular matrix callogen adhesive proteins cell signaling role
Determine if each statement applies to facilitated diffusion, active transport, or both.
FACILITATED DIFFUSION: -Molecules move down their concentration gradient. ACTIVE TRANSPORT: -Molecules move against their concentration gradient. -Requires energy. -Transport proteins are specific for the structures of individuals molecules. BOTH: -Molecules move through a transport protein in the membrane.
Compare Facilitated and Simple Diffusion Unlike simple diffusion, facilitated diffusion requires energy expenditure by the cell. True False
FALSE
Determine if each statement applies to facilitated diffusion, active transport, or both.
Facilitated diffusion - Molecules move down their concentration gradient Active transport - Molecules move against their concentration gradient - Requires energy Both - Molecules move through a transport protein in the membrane - Transport proteins are specific for the structures of individual molecules
Determine if each statement applies to facilitated diffusion, active transport, or both.
Facilitated diffusion - Molecules move down their concentration gradient. Active transport - Molecules move against their concentration gradient. Requires energy (ATP). Both - Carriers are specific for the structures for individual molecules. Molecules move through a protein carrier in the membrane.
Aquaporin allows water molecules to move very rapidly across a plasma membrane. What would be the best definition of this process?
Facilitated diffusion using a channel
Glucose is taken up by red blood cells by binding to a specific pocket in a membrane protein that then allows it to cross the membrane and move down its concentration gradient. What would be the best explanation of this process?
Facilitated diffusion using a transporter
Cells are placed in a solution of glucose. The rate at which glucose enters the cells increases as the concentration of the glucose solution is increased. Eventually the rate of glucose movement stops increasing. How is glucose moving into cells?
Facilitated diffusion via a carrier protein.
You are studying the diffusion of calcium ions from the extracellular fluid into the cells of a tissue. Cell lines that have a mutation in the gene for an unknown, membrane-bound protein are unable to transport calcium ions into the tissue. Using this evidence, do you hypothesize that calcium ions are transported by simple or facilitated diffusion, and why?
Facilitated diffusion, because calcium ions are charged and cannot move through the phosopholipid bilayer and because a protein appears to be necessary for the movement of calcium ions.
When taking oral medications, several lipid cell membrane barriers have to be passed before the hydrophilic drug can reach circulation. What is the most likely method of transport mechanism the drug would use to cross membranes?
Facilitated diffusion.
A 5% urea solution is hypotonic to a 10% urea solution.
False
Photosynthetic pigments are found in the plasma membrane of a plant cell. T/F?
False
Sucrose concentration is higher in the cytoplasm than in the extracellular environment. Na+ concentration is higher in the extracellular environment than in the cytoplasm. Animal cells can take up sucrose against its concentration gradient using a Na+/sucrose symporter. Indicate if the following statements are true or false. In the Na+/sucrose symporter, Na+ is also moving against its concentration gradient.
False
Sucrose concentration is higher in the cytoplasm than in the extracellular environment. Na+ concentration is higher in the extracellular environment than in the cytoplasm. Animal cells can take up sucrose against its concentration gradient using a Na+/sucrose symporter. Indicate if the following statements are true or false. A Na+/sucrose antiporter would be capable of moving sucrose into the cell while moving Na+ out of the cell.
False
Sucrose concentration is higher in the cytoplasm than in the extracellular environment. Na+ concentration is higher in the extracellular environment than in the cytoplasm. Animal cells can take up sucrose against its concentration gradient using a Na+/sucrose symporter. Indicate if the following statements are true or false. A symporter works by making the phospholipid bilayer more permeable to ions and sucrose.
False
Sucrose concentration is higher in the cytoplasm than in the extracellular environment. Na+ concentration is higher in the extracellular environment than in the cytoplasm. Animal cells can take up sucrose against its concentration gradient using a Na+/sucrose symporter. Indicate if the following statements are true or false. Since the Na+/sucrose symporter exchanges a single sucrose for a single Na+, it can also be considered a uniporter.
False
TF: Inhibiting one step in a biochemical pathway will not have any affect on the rates of the other reactions in the pathway.
False
TF: The release of the last phosphate from ATP is endergonic.
False
TF: They are totally water soluble.
False
TF: They are used in DNA replication
False
TF: Unlike simple diffusion, facilitated diffusion requires energy expenditure by the cell.
False
TF: When ATP is hydrolyzed to form ADP, the energy is released into the cytoplasm where enzymes use it to run endergonic reactions.
False
TRUE OR FALSE Osmosis describes the movement of water from an area of high to low solute concentration
False
The formation of ATP as a result of the activity of the electron transport system is termed substrate-level phosphorylation. T/F?
False
Unlike simple diffusion, facilitated diffusion requires energy expenditure by the cell.
False
Use image 11 If the end product of the biochemical pathway in the animation increases, it would eventually result in an increase in substrate 2.
False
Use image 7 TF: Phosphoenolpyruvate is a product
False
Use image 7 TF: Pyruvate is a substrate
Fase
Match the properties described with one of the four components of a membrane. Phospholipid bilayer
Forms a semipermeable barrier. Can allow diffusion of gases.
You plant a seed in a pot and water it. A few days later you see small green leaves appear out of soil. You put a jar over the plant and monitor O2 and CO2 levels during the day and then again at night. Match the appropriate activities and levels of water, carbon dioxide, and oxygen over the course of a day. Water: A) backbone of cellulose B) increases during the day C) leaves leaf through stomata D) decreases at night E) enters leaf through stomata F) reduced in the Calvin cycle G) source of electrons for photosynthesis H) oxidized in photosystem II I) decreases during the day J) increases at night
G) source of electrons for photosynthesis H) oxidized in photostem II
Which statement regarding G-protein activation is TRUE?
G-proteins are activated by active G-protein-linked receptors.
For each substance determine if it would cross a membrane by simple or facilitated diffusion. Simple Diffusion
Gasses Ethanol Water
Rank these reactions from least to most energetically favorable. ATP to ADP and Pi, -7.3kcal/mol Glucose-6-P to Fructose-6-P, +0.4kcal/mol Glucose to Glucose-6-P, +3.3kcal/mol PEP to pyruvate, -14.8kcal/mol
Glucose to Glucose-6-P, +3.3kcal/mol Glucose-6-P to Fructose-6-P, +0.4kcal/mol ATP to ADP and Pi, -7.3kcal/mol PEP to pyruvate, -14.8kcal/mol
A cellular protein is involved in the cotransport of glucose and sodium ions into the cell. What would be the most likely outcome if sodium is blocked from moving through this transporter?
Glucose would be unable to move without the movement of sodium into the cell, down its concentration gradient.
2 ATP
Glycolysis Citric Acid Cycle (Kreb)
Which of the following molecules are most likely to pass through the membrane by facilitated diffusion?
H2O and sucrose
Match the properties described with one of the four components of a membrane. Interoir Protein Network
Helps determine the overall shape of a cell.
Calculate the Dissociation Constant (Kd)
I dont know yet
Types of Membrane Proteins Label each protein by its type of attachment.
Image 1
stages of cell signaling in the correct order
Image 12
Label the molecules in this figure of the activation of a G-protein coupled receptor.
Image 13
Label the molecules in this figure of the activation of a receptor tyrosine kinase.
Image 14
Label the molecules in this figure showing how cAMP functions as a second messenger.
Image 15
Label the molecules in this figure showing how IP3 and DAG function as second messengers.
Image 16
Match each term with the correct cell or extracellular matrix component.
Image 17
Match each step in the formation of collagen fibers with the correct image.
Image 18
Label the components of the four different types of anchoring junctions.
Image 19
Mark the flow of water with an arrow for cells that have been placed in solutions of differing tonicity. Indicate what will happen to a plant and animal cell under each of these conditions. Direction of osmosis Outside isotonic outside is hypertonic outside is hypotonic
Image 2
Label the diagram illustrating how cadherin works.
Image 20
Use the diagram to identify dermal, ground, and vascular tissue in the leaf, stem and root of a plant.
Image 21
Know the cellular respiration diagram.
Image 3
Phases of glycolysis
Image 6
Match type of inhibitor to enzyme curve Identify which enzyme would result in the type of inhibition shown in each graph.
Image 8
Proteasome matching Place the following images in the correct order to show protein degradation by proteasome.
Image 9
Digoxin is an inhibitor of Na+/K+ ATPase that is used to treat irregular heartbeats (medical term: atrial fibrillation). Digoxin slows the heartbeat by raising intracellular calcium levels. What is the most reasonable explanation for how digoxin can raise intracellular calcium concentrations through inhibiting Na+/K+ ATPase?
Inhibiting Na+/K+ ATPase results in a higher than normal intracellular Na+ concentration. This reduces the effectiveness of the Na+/Ca2+ antiporter. As a result, intracellular Ca2+ levels increase.
Digoxin is an inhibitor of Na⁺/K⁺ ATPase that is used to treat irregular heartbeats (medical term: atrial fibrillation). Digoxin slows the heartbeat by raising intracellular calcium levels. What is the most reasonable explanation for how digoxin can raise intracellular calcium concentrations through inhibiting Na⁺/K⁺ ATPase?
Inhibiting Na⁺/K⁺ ATPase results in a higher than normal intracellular Na⁺ concentration. This reduces the effectiveness of the Na⁺/Ca²⁺ antiporter. As a result, intracellular Ca²⁺ levels increase.
Consider the biochemical pathways illustrated below. If product D is abundant, why is it preferable to inhibit E2 rather than E1? A--E1-->B--E2-->C--E3-->D B--E4-->E
Inhibition of E2 will prevent the production of D, but still allow synthesis of E.
What happens when the coenzyme NAD+ gains an H atom?
It also gains an electron causing it to be reduced.
Based on the reaction in the animation, what can you say about the change in free energy of the cleavage of sucrose into glucose and fructose?
It is negative and the reaction is exergonic.
Which of the following statements about inositol triphosphate is FALSE?
It is synthesized by the enzyme phosphatase.
Nicotine is a molecule that is chemically similar to acetylcholine and binds to the same receptors. What affect will nicotine have on the cell shown in the animation?
It will open sodium channels.
You plant a seed in a pot and water it. A few days later you see small green leaves appear out of soil. You put a jar over the plant and monitor O2 and CO2 levels during the day and then again at night. Match the appropriate activities and levels of water, carbon dioxide, and oxygen over the course of a day. Carbon dioxide: A) backbone of cellulose B) increases during the day C) leaves leaf through stomata D) decreases at night E) enters leaf through stomata F) reduced in the Calvin cycle G) source of electrons for photosynthesis H) oxidized in photosystem II I) decreases during the day J) increases at night
J) increases at night I) decreases during the day A) backbone of cellulose F) reduced in the Calvin cycle E) enters leaf through stomata
Low-density lipoprotein (LDL) enters the cell via receptor-mediated endocytosis. What is the most likely reason for why LDL is not simply transported into the cell using a channel or transporter protein?
LDL is too large for a channel or transporter protein
Relate lipid composition to different types of membranes and membrane walls
Membranes are made of of lipids, proteins, and carbohydrates Phospholipid bilayer -amphitatic (polar phosphate head and nonpolar lipid tail) Length of the nonpolar tails Shorter tail = less interaction, membrane has more fluidity Longer tail = more interaction, membrane has less fluidity
Determine if each statement applies to facilitated diffusion, active transport, or both. Active Transport
Molecules move against their concentration gradient Requires energy
Determine if each statement applies to facilitated diffusion, active transport, or both. Facilitated Diffusion
Molecules move down their concentration gradient
Determine if each statement applies to facilitated diffusion, active transport, or both. Both
Molecules move through a transport protein in the membrane Transport proteins are specific for the structures of individual molecules
facilitated diffusion
Movement of specific molecules across cell membranes through protein channels
During oxidative phosphorylation, _____ and FADH2 are oxidized to power ATP production
NADH
Electrons are brought to the electron transport system by the oxidation of
NADH and FADH2.
The oxidation of NADH results in the formation of more ATP molecules compared to the oxidation of FADH2 because
NADH enters the electron transport chain at an earlier point than FADH2.
An electron carrier called __________ drives the Calvin cycle
NADPH
Paraquat is an herbicide that competes with FD (Ferredoxin) for the electrons that are released from Photosystem I after it is struck by light. Which of the following products of the light reaction would paraquat prevent from forming?
NADPH
an electron carrier called ______ drives the Calvin cycle
NADPH
Which of the following molecules might be an intracellular signaling molecule?
NO
Match the properties described with one of the four components of a membrane. Cell Surface Marker
Often carbohydrate attached to a lipid or protein.
Cellular Respiration
Produces CO2 O2 exits as H2O Consumes Glucose
Use image 10 If a chemical that inhibits Enzyme #3 was added to the system containing the biochemical pathway illustrated in the animation, which of the following would result?
Product #2 would accumulate in the system. Substrate #3 would accumulate in the system. Substrate #4 would be depleted in the system. The final product would be depleted in the system
Molecules capable of enzymatic activity include...
RNA and proteins
Lipoproteins like LDL and HDL transport lipids and proteins through the blood stream. Receptors on cells can bind to the lipoproteins and remove them from the blood, using the lipids for energy and to produce membranes. Which of the following mechanisms would be used to move a lipoprotein into a cell?
Receptor-mediated endocytosis
Lipoproteins like LDL and HDL transport lipids and proteins through the bloodstream. Receptors on cells can bind to the lipoproteins and remove them from the blood, using the lipids for energy and to produce membranes. Which of the following mechanisms would be used to move a lipoprotein into a cell?
Receptor-mediated endocytosis
Rate of diffusion is affected by different factors. Predict which scenario would have the fastest rate of diffusion.
Small molecules that are highly concentrated in warm temperatures.
Why must the electron transport chain proteins and molecules be embedded in a membrane?
So that protons can be compartmentalized and form a gradient
Active Transport
Substances are transported from a lower concentration to a higher concentration working against the concentration gradient. This type requires the addition of energy ATP.
What happens to sucrase when it binds to sucrose?
Sucrase goes through a conformational change.
A mutation occurred in the gene that encodes the enzyme sucrase, resulting in a single amino acid substitution in the active site of the enzyme; a polar amino acid changed to a nonpolar amino acid. What is probably the result of this mutation.
Sucrase will not be able to bind sucrose in the active site.
For each substance determine if it would cross a membrane by simple or facilitated diffusion. Facilitated Diffusion
Sugars Salts Proteins
GLUT1 deficiency syndrome is a rare genetic disorder where mutations in the gene encoding GLUT1 reduce or eliminate the function of the GLUT1 protein. Affected individuals suffer from seizures along with a number of potential neurological problems. What would be the most effective therapy to treat patients suffering from this disorder?
Switch to a diet containing carbohydrates other than glucose to circumvent the deficient transport
GLUT1 is a glucose transporter that is responsible for the facilitated diffusion of glucose across the blood-brain barrier. GLUT1 deficiency syndrome is a rare genetic disorder where mutations in the gene encoding GLUT1 reduce or eliminate the function of the GLUT1 protein. Affected individuals suffer from seizures along with a number of potential neurological problems. What would be the most effective therapy to treat patients suffering from this disorder?
Switch to a diet containing carbohydrates other than glucose to circumvent the deficient transport.
TF: The sodium channels in the cell membrane have receptor sites for acetylcholine.
TRUE
TF: Intracellular receptors bind to specific nucleotide sequences.
TRue
Photosynthesis
Take in CO2 Converts H2O to O2 Produces organic molecules Found only in photoautotrophs
Why is it possible for Na+ to enter the cell when the channel is open?
The Na+/K+ pump previously built a high concentration of Na+ on the outside of the cell, so Na+ is diffusing.
Alzheimer's disease is characterized by an accumulation of proteins such as beta-amyloid protein in the cells. Beta-amyloid mRNA levels do not increase in patients with Alzheimer's disease. Explain how beta-amyloid protein levels increase in these patients' cells.
The beta-amyloid proteins are not broken down and recycled.
Why does a human red blood cell lyse when placed in a hypotonic solution while a plant cell does not?
The cell wall of the plant prevents the membrane from swelling too much. (p105)
The plasma membrane Ca2+-ATPase is a pump that functions in the primary active transport of Ca2+ out of the cell. What features do you expect of this pump and the cellular environment? Choose all that apply.
The extracellular Ca2+ concentration is higher than the intracellular Ca2+ concentration It hydrolyzes ATP It is capable of undergoing a conformational change The affinity for Ca2+ is low when the pump is bound to phosphate.
Which best represents an example of carbon fixation?
The incorporation of CO2 into organic molecules.
receptor-mediated endocytosis
The movement of specific molecules into a cell by the inward budding of membranous vesicles containing proteins with receptor sites specific to the molecules being taken in; enables a cell to acquire bulk quantities of specific substances.
If a ligand were stuck in the G-protein-linked receptor, what would be the effect to the cell?
The pathway would be over active.
Based on the animation, which of the following observations is true?
The product from one reaction served as the substrate for the next reaction.
The energy for producing organic molecules in plants is directly driven by:
The use of light to provide electrons for oxidation and reduction reactions.
What function do many B vitamins serve in the production of energy?
They function as co-enzymes.
Why is pyruvate converted to lactate in anaerobic conditions?
To regenerate NAD+ from NADH and keep glycolysis functioning.
If a cell is placed in an isotonic medium, there will be no net movement of water.
True
Plastoquinone is the primary electron acceptor for electrons leaving photosystem II. T/F?
True
Sucrose concentration is higher in the cytoplasm than in the extracellular environment. Na+ concentration is higher in the extracellular environment than in the cytoplasm. Animal cells can take up sucrose against its concentration gradient using a Na+/sucrose symporter. Indicate if the following statements are true or false. For the symporter to work, the cell must first establish a Na+ concentration gradient.
True
Sucrose concentration is higher in the cytoplasm than in the extracellular environment. Na+ concentration is higher in the extracellular environment than in the cytoplasm. Animal cells can take up sucrose against its concentration gradient using a Na+/sucrose symporter. Indicate if the following statements are true or false. Moving sucrose against its concentration gradient is a form of active transport.
True
TF: Calcium ions serve as second messengers.
True
TF: Correct Creatine-P to creatine has a ΔG of -11kcal/mole and thus can be used to generate ATP from ADP.
True
TF: In a biochemical pathway, the product released by the first enzyme becomes the substrate for the second enzyme.
True
TF: Inactivation of the alpha subunit occurs when its own phosphorylase activity removes a phosphate from the GTP.
True
TF: Once phosphates are released from ATP they can be added back in an endergonic reaction.
True
TF: They can act as cell surface receptors.
True
TF: They can aid in the transportation of molecules across membranes.
True
TF: They can be enzymes.
True
TF: When ATP is used in a reaction, the last phosphate is transferred to the substrate.
True
TF: Whenever a molecule is oxidized, another molecule must be reduced.
True
TRUE OR FALSE Diffusion is the movement of a molecule from an area of high to low concentration
True
TRUE OR FALSE Movement of molecules down their concentration gradient can drive the movement of a different molecule against its concentration gradient.
True
Use image 7 TF: Mg+2 ion is a cofactor
True
Use image 7 TF: Pyruvate kinase is an enzyme
True
Sucrase uses ____ to cleave sucrose into two monosaccharides.
Water
Leaves exposed to light of wavelength 680 nm alone or 700nm alone will undergo a similar amount of photosynthesis. However, when both wavelengths are shined at the same time more than double the amount of photosynthesis occurred. Which of the following best explains this observation?
When both wavelengths are used, electrons can pass from photosystem II to photosystem I generating more ATP.
After hand washing your clothes, your fingers appear wrinkled because they've taken in water. What is the most plausible explanation?
Your skin is hypertonic to the water.
When inactive, the alpha subunit of the G-protein is bound to
a GDP molecule.
Consider the biochemical pathway used to synthesize the amino acid proline. A large increase in the level of proline will most likely lead to
a decrease in proline production.
Concentration Gradient
a difference between the concentration on the inside of the membrane and that on the outside
Exocytosis
a process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane with the cell membrane.
A hydrogen atom consists of
a proton and an electron.
Which of the following molecules are most likely to pass through the membrane by facilitated diffusion? a. H2O and sucrose b. H2O and O2. c. CO2 and O2. d. CO2 and H2O.
a. H2O and sucrose
Simple diffusion is defined as the movement of a. molecules from areas of higher concentration to areas of lower concentration. b. molecules from areas of lower concentration to areas of higher concentration. c. water molecules across a membrane. d. gas molecules across a membrane. e. gas or water molecules across a membrane.
a. molecules from areas of higher concentration to areas of lower concentration.
chlorophyll ________ best in red and blue light
absorbs
Fatty acids and some amino acids are converted directly into _____________ for ATP production.
acetyl CoA
Before entering the citric acid cycle, also called the Krebs cycle, pyruvate is converted to
acetyl-CoA.
When a cell receives a signal, various cellular responses can occur. Classify which type of response each group of proteins could regulate. Transcription factor
activate gene expression change in sex characteristics
Determine if each statement applies to facilitated diffusion, active transport, or both Molecules move against their concentration gradient
active transport
Determine if each statement applies to facilitated diffusion, active transport, or both Requires energy
active transport
molecules move against thier concentration gradient; requires energy
active transport
The second messenger cAMP is synthesized by the enzyme
adenylyl cyclase.
Oxygen is the final electron acceptor in ______ respiration.
aerobic
When a cell receives a signal, various cellular responses can occur. Classify which type of response each group of proteins could regulate. Structural proteins
altering cell shape causing cell movement
In osmosis, water molecules move across membranes through aquaporins from
an area of high water concentration to an area of lower water concentration.
The ligand that activates the G-protein linked receptor is ______.
an extracellular signaling molecule
The term ------- describes cellular respiration in the absence of --------.
anaerobic , oxygen
Using your knowledge about the movement of molecules in and out of a cell, pair up the type of transportation mode to the most accurate description of its mechanism 1. symporter 2. uniporter 3. biporter 4. antiporter Two ions or molecules moving in opposite directions
antiporter
An example of __________ is when cells release signals that affect themselves and nearby target cells.
autocrine signaling
Facilitated diffusion requires a. enzymes. b. carrier proteins. c. lipid carriers. d. carbohydrate carriers. e. lipid or carbohydrate carriers.
b. carrier proteins.
Exocytosis is a process by which cells a. release substances from the cell through pores in the cell membrane. b. release substances from the cell via vesicles. c. release substances from the cell via carrier proteins. d. bring in substances from the outside via vesicles. e. bring in substances from the outside via pores in the cell membrane.
b. release substances from the cell via vesicles.
Which of the following is the most direct source of energy for cotransport? a. the movement of one of the transported substances up its concentration gradient b. the movement of one of the transported substances down its concentration gradient c. ATP hydrolysis d. ATP formation e. cotransport requires no energy
b. the movement of one of the transported substances down its concentration gradient
Red blood cells put in a hypotonic solution will
be destroyed by hemolysis
Using your knowledge about the movement of molecules in and out of a cell, pair up the type of transportation mode to the most accurate description of its mechanism 1. symporter 2. uniporter 3. biporter 4. antiporter This is not a transporter
biporter
a 430 nm pigment likely absorbs _____ light
blue
Determine if each statement applies to facilitated diffusion, active transport, or both Molecules move through a protein in the membrane
both
Determine if each statement applies to facilitated diffusion, active transport, or both Transport proteins allow the movement of ions and hydrophilic molecules across the membrane
both
molecules move through a protein carrier in the membrane; carriers are specific to the structure of individual molecules (facilitated diffusion/ active transport/ both)
both
Intracellular receptors usually contain binding sites for
both DNA and signaling molecules.
The epidermis (top layer of skin) does not have a blood supply. Nutrients reach the epidermis
by diffusing through the tissue fluid from blood vessels in the dermis.
Aquaporin allows water molecules to move very rapidly across a plasma membrane. What would be the best definition of this process? a. Facilitated diffusion using a transporter b. Active transport using a transporter c. Facilitated diffusion using a channel d. Active transport using a channel
c. Facilitated diffusion using a channel
Of the three basic types of endocytosis, what is a unique feature of receptor-mediated endocytosis? a. it is used to transport material into the cell b. it is non-specific c. it involves clathrin-coated pits d. it involves transport of material into e. the cell through pores in the cell membrane e. it can be used both to import and export materials
c. it involves clathrin-coated pits
Sea water is approximately 3% salt. Sea water is hypertonic to tissues of freshwater fish. Their tissue contain - a. 3% salt b. more than 3% salt c. less than 3% salt
c. less than 3% salt
Red blood cells put in a hypertonic solution will a. not be affected in any way. b. form linear edges. c. shrivel and become crenated. d. be destroyed by hemolysis.
c. shrivel and become crenated.
When sugar is mixed with water, equilibrium is reached when Required information View the animation below, then complete the quiz to test your knowledge of the concept. Play Video When sugar is mixed with water, equilibrium is reached when a. molecules of sugar stop moving. b. water and sugar molecules are moving at the same speed. c. the dissolved sugar molecules are evenly distributed throughout the solution. d. there is the same number of water molecules as dissolved sugar molecules. e. water and sugar molecules are at an equal concentration.
c. the dissolved sugar molecules are evenly distributed throughout the solution.
The Calvin cycle performs __________ during photosynthesis.
carbon fixation
the Calvin cycle performs _______ during photosynthesis
carbon fixation
Facilitated diffusion requires
carrier proteins
Facilitated diffusion requires
carrier proteins.
Animal cells attach to each other using _______ proteins.
cell junction
Animal cells attach to each other using ___________ proteins.
cell junction
In extracellular signaling, ligands bind to _________________
cell surface receptors.
Place the extracellular cell feature with the appropriate cell type. Plant Cell
cell wall cellulose cross-linked glycans usually thick and rigid
_______ captures the light energy for photosynthesis
chlorophyll
__________ captures the light energy for photosynthesis.
chlorophyll
lipid composition
cholesterol and long chain fatty acids are more packed together and make the membrane less fluid, the ones that are unsaturated and increase fluidity
in anabolic reactions that involve the synthesis of a large molecule from smaller precursor molecules, NADH and ATP are _________ when they provide the needed electrons or energy
consumed
Membrane-bound signals bind to receptors on adjacent cells in the process of ______________________
contact-dependent signaling
A phospholipid will laterally diffuse in a plasma membrane faster than an integral membrane protein. What is the simplest explanation for this phenomenon? a. A phospholipid is more hydrophobic than an integral membrane protein b. A phospholipid has greater rotational movement than an integral membrane protein c. The enzyme Flippase can rapidly flip phospholipids across the bilayer but it cannot do the same for integral membrane proteins d. A phospholipid is smaller than an integral membrane protein
d. A phospholipid is smaller than an integral membrane protein
Which of the following is true of the fluid mosaic model of membrane structure? a. Membranes behave more like a solid than a liquid. b. Lipids can flip from one leaflet to another as easily as they can move laterally in a membrane. c. Proteins can easily move across membranes. d. Proteins can easily move laterally through membranes.
d. Proteins can easily move laterally through membranes.
Red blood cells put in a hypotonic solution will a. not be affected in any way. b. form linear edges. c. shrivel and become crenated. d. be destroyed by hemolysis
d. be destroyed by hemolysis
Certain white blood cells engulf microorganisms and digest them within the cell. A mutation that prevents this internalization would directly affect a. pinocytosis. b. osmosis. c. receptor-mediated exocytosis. d. phagocytosis. e. diffusion.
d. phagocytosis.
Osmosis is best defined as the movement of a. molecules from an area of high concentration to an area of lower concentration. b. molecules from an area of low concentration to an area of higher concentration. c. water molecules across a membrane from an area of low water to an area of higher concentration. d. water molecules across a membrane from an area of high water concentration to an area of lower concentration.
d. water molecules across a membrane from an area of high water concentration to an area of lower concentration.
An animal cell encounters a new type of bacterium. The ordered process of phagocytosis that is likely to be used by the animal cell to engulf and consume the bacterium would be
detection, ingestion, fusion with lysosome, phagolysosome, digestion.
When you breathe, oxygen moves from your lungs into your blood and then into tissues. To do this, oxygen moves across membranes by ______ and from ______ concentration of oxygen.
diffusion, higher to lower
In _______________, signals pass through a cell junction from one cell to adjacent cells.
direct intracellular signaling
Some protists, such as paramecia, live in an extremely hypotonic environment and have contractile vacuoles that
discharge excess water that has moved into the cell.
The hormone insulin is a protein produced in the pancreas and then secreted into the blood stream after a meal to increase glucose uptake by tissues. Which of the following mechanisms would be used to secrete insulin from the pancreas? a. Active transport b. Facilitated diffusion c. Diffusion d. Endocytosis e. Exocytosis
e. Exocytosis
Sugars can be transported into cells against their concentration gradient because of a. osmosis. b. simple diffusion. c. facilitated diffusion. d. antiport with Na+. e. symport with Na+.
e. symport with Na+.
Intracellular receptors may be found
either in the cytoplasm or the nucleus.
H2O provides ________ for the light reactions
electrons
H₂O provides __________ for the light reactions.
electrons
NADH and FADH2 donate ______ at different points in the electron transport chain
electrons
Cells release signals that travel long distances to affect target cells during ______________
endocrine signaling
The light reactions involve a series of _________ conversions.
energy
the light reactions involve a series of _______ conversions
energy
RNA exposed to a/an ____________ will release ____________ which the cell can recycle.
exonuclease nucleotides
Determine if each statement applies to facilitated diffusion, active transport, or both Molecules move down their concentration gradient
facilitated diffusion
molecules move down thier concentration gradient in
facilitated diffusion
Animal cells can take up sucrose against its concentration gradient using a Na+/sucrose symporter. Indicate if the following statements are true or false. In the Na+/sucrose symporter Na+ is also moving against its concentration gradient
false
Animal cells can take up sucrose against its concentration gradient using a Na+/sucrose symporter. Indicate if the following statements are true or false. A symporter works by making the membrane more permeable to ions and sucrose
false
If a pump moves 3 positive ions out and 2 positive ions in against their concentration gradients, the membrane potential in the cell will become more positive. (true/false)
false
Indicate whether the following statements about membrane proteins are TRUE OR FALSE They are totally water soluble
false
Indicate whether the following statements about membrane proteins are TRUE OR FALSE They are used in DNA replication
false
TRUE OR FALSE enzymes are consumed in chemical reactions and must therefore be replenished
false
TRUE OR FALSE in prokaryotic cells, the electron transport system occurs in the mitochondria
false
TRUE OR FALSE metabolism refers to only those reactions that release energy
false
TRUE OR FALSE the Calvin cycle is only capable of fixing carbon dioxide in the dark
false
TRUE OR FALSE the rate of photosynthesis is much greater in green light than red light
false
TRUE OR FALSE unlike animals, plants lack a cell junction where small molecules can move from one cell to another cell
false
Mammals like caribou that live in the arctic often use different lipid types in their legs. Legs are more susceptible to heat loss than internal organs, which are closer to the body core and stay warmer. Which adaptations would you expect for lipids in caribou legs? The lipids would be more saturated (T/F)
false, (Unsaturated lipids are more fluid at lower temperatures and so the lipids in the legs of caribou would be more unsaturated)
The breakdown of organic molecules without oxygen is called __________.
fermentation
Cell connections called ______ help adjacent animal cells communicate.
gap junctions
Cell connections called _______________ help adjacent animal cells communicate.
gap junctions
In cellular respiration, carbon dioxide is formed from the oxidation of the following:
glucose
Which of the following is the correct equation for aerobic cellular respiration?
glucose + 6 O2 → 6 CO2 + 6 H2O + energy intermediates + heat
carotenoids absorb light in the blue and ______ regions of the spectrum
green
Animal cells use _____ to attach to the extracellular matrix.
hemidesmosomes
Animal cells use _______________ to attach to the extracellular matrix.
hemidesmosomes
ATP synthase uses an electrochemical gradient of ______ to produce ATP
hydrogen ions
What is the source of energy used to power the sodium-potassium pump?
hydrolysis of ATP
Channel Protein
hydrophilic interior that provides an aqueous channel through which polar molecules can pass when the channel is open
Electron transport chain
image 4
Macromolecules and cellular respiration
image 5
GLUT1 is a glucose transporter that is responsible for the facilitated diffusion of glucose across the blood-brain barrier. GLUT1 deficiency syndrome is a rare genetic disorder where mutations in the gene encoding GLUT1 reduce or eliminate the function of the GLUT1 protein. Affected individuals suffer from seizures along with a number of potential neurological problems. What is the link between GLUT1 dysfunction and these neurological complications?
insufficient diffusion of glucose from the blood to the brain
The movement of protons through ATP synthase occurs from the
intermembrane space to the matrix.
When a double bond is present it does what to the lipid?
it becomes unsaturated
Of the three basic types of endocytosis, what is a unique feature of receptor-mediated endocytosis?
it involves clathrin-coated pits
Integral membrane proteins can move _______ in a membrane.
laterally
Sea water is approximately 3% salt. Sea water is hypertonic to tissues of freshwater fish. Their tissue contain -
less than 3% salt
Sea water is approximately 3% salt. If sea water is hypertonic to tissues of freshwater fish you can conclude their tissues contain
less than 3% salt.
Photosynthesis uses _________ to produce ATP, NADPH, and O₂.
light energy
photosynthesis uses ______ to produce ATP, NADPH, and O2
light energy
O2 is produced in the _______
light reactions
O₂ is produced in the ____________
light reactions
Water is converted to oxygen and releases electrons in the __________.
light reactions
water is converted to oxygen and releases electrons in the _______
light reactions
Phospholipids
lipid layer that forms the foundation of a cell's membranes us a bilayer formed of these
The most likely outcome of red blood cells with internal salt concentrations of 0.85% being placed in a 4% salt solution is the cells would
lose water and shrink
Enzymes catalyze reactions by
lowering activation energy.
How often can a sucrase molecule be used to hydrolyze sucrose?
many times
Plant cells are attached to each other by the _______.
middle lamella
Plant cells are attached to each other by the ______________
middle lamella.
the electron transport chain is located in the inner membrane of the ________
mitochondria
Simple diffusion is defined as the movement of
molecules from areas of higher concentration to areas of lower concentration.
Which of the following cell signaling molecules crosses the cell membrane the easiest?
molecules that are small and lipid-soluble
types of membranes
mucous, serous, cutaneous, synovial
Where is sucrase found in the human body?
on the microvilli of the small intestine
Consider the biochemical pathway below, where A, B, and C are substrates and products and E1 and E2 are the enzymes that catalyze the reactions. Enzyme 1 (E1) can utilize A--E1-->B--E2-->C
only A as substrate.
in the reaction pyruvate + NADH --> lactate + NAD, NADH is being _________
oxidized
Cells obtain energy by ________ food molecules such as glucose.
oxidizing
During aerobic respiration, the last carrier protein transfers a pair of electrons to...
oxygen
the final electron acceptor of the electron transport chain is ______
oxygen
In __________________, cells release signals that affect nearby target cells.
paracrine signaling
Subatomic particels
particles much smaller than atoms.
Intracellular receptors are activated by signaling molecules that __________ the plasma membrane.
pass through
Certain white blood cells engulf microorganisms and digest them within the cell. A mutation that prevents this internalization would directly affect
phagocytosis.
In membranes __________ associate to form two layers.
phospholipids
Junctions called _______ permit communication between plant cells.
plasmodesmata
Junctions called __________ permit communication between plant cells.
plasmodesmata
Creation of a proton gradient by the electron transport chain represents
potential energy
Endocytosis
process by which a cell takes material into the cell by INfolding of the cell membrane
in catabolic reactions that involve the breakdown of a molecule into smaller subunits, such as glucose to pyruvate, NADH and ATP are __________
produced
Protein exposed to a/an ____________ will release ____________ which the cell can recycle.
proteasome amino acids
Most types of enzyme-linked receptors function as ___________________
protein kinases.
Larger _______ float within the bilayer.
proteins
Phospholipid Bilayer
provides flexiable matric and imposes a barrier
If glycolysis was blocked in yeast, which of the following would decrease in concentration?
pyruvate
Diffusion
random motion causing a net movement of these substance from regions of high concentration to region of a lower concentration
The Epstein-Barr Virus (EBV), which causes mononucleosis, binds to receptors on B-cells, and tricks them into taking them inside. The most likely mechanism by which EBV gets into the host cell would be
receptor-mediator endocytosis.
In the reaction pyruvate + NADH --> lactate + NAD, pyruvate is being ________
reduced
a green pigment likely ____ green light
reflects
Exocytosis is a process by which cells
release substances from the cell via vesicles.
Solute
salt, is the substance being dissolved.
Isotonic
same osmotic concentration
A red blood cell placed in a hypertonic medium will
shrink.
Red blood cells put in a hypertonic solution will
shrivel and become crenated.
Which of the following will pass through a cell membrane most easily?
small nonpolar molecules
which scenario would have the fastest rate of diffusion? _______ molecules that are highly concentrated in _______ temperatures
small, warm
The sodium-potassium pump functions to pump
sodium ions out of the cell and potassium ions into the cell.
Hypertonic
solution with higher concentration
Hypotonic
solution with lower concentration
Passive Transport
some ions and molecules through the membrane fairly easily and do so because of a concentration gradient
In mammals, receptors for _________________ are intracellular.
steroid hormones
The Calvin cycle takes place in the ________ of chloroplasts.
stroma
Facilitated diffusion is used to transport
sugars and amino acids.
Sugars can be transported into cells against their concentration gradient because of
symport with Na+.
Sugars can be transported into cells against their concentration gradient because of
symport with Na⁺.
Using your knowledge about the movement of molecules in and out of a cell, pair up the type of transportation mode to the most accurate description of its mechanism 1. symporter 2. uniporter 3. biporter 4. antiporter The movement of two ions or molecules into or out of a cell
symporter
As a result of the ligand binding to its site on the G-protein-linked receptor,
the G-protein changes conformation and GTP replaces the GDP on the alpha subunit.
When sugar is mixed with water, equilibrium is reached when
the dissolved sugar molecules are evenly distributed throughout the solution.
Transdermal drug patches, such as nicotine patches, are applied to the skin. The drug is applied in a relatively high dosage to the inside of the patch, which is worn on the skin for periods of time. The drugs enter the bloodstream directly through the skin. Theoretically, how do the patches work?
the drug will move into the blood, through diffusion, for a long period of time, maintaining a constant concentration of drug in the blood
In feedback inhibition, the inhibitor of the biochemical pathway is often
the final product of the biochemical pathway.
active transport
the movement of materials through a cell membrane using energy
Which of the following is the most direct source of energy for cotransport?
the movement of one of the transported substances down its concentration gradient
When the acetylcholine binds to the receptor sites...
the sodium channels open.
When the acetylcholine receptor sites are not occupied...
the sodium channels remain closed.
Animal cells form close seals between cells using _______.
tight junctions
Animal cells form close seals between cells using _______________
tight junctions.
Animal cells can take up sucrose against its concentration gradient using a Na+/sucrose symporter. Indicate if the following statements are true or false. For the symporter to work, the cell must first establish a Na+ concentration gradient.
true
Animal cells can take up sucrose against its concentration gradient using a Na+/sucrose symporter. Indicate if the following statements are true or false. Moving sucrose against its concentration gradient is a form of active transport
true
Due to the unequal transport of sodium and potassium ions by the Na-K pump, a membrane potential is generated. (true/false)
true
Indicate whether the following statements about membrane proteins are TRUE OR FALSE They can act as cell surface receptors
true
Indicate whether the following statements about membrane proteins are TRUE OR FALSE They can aid in the transportation of molecules across membranes
true
Indicate whether the following statements about membrane proteins are TRUE OR FALSE They can be enzymes
true
TRUE OR FALSE catholic and anabolic reactions in living cells involve the transfer of electrons from one molecule to another in reduction-oxidation reactions
true
TRUE OR FALSE if oxygen is present, pyruvate will be converted to acetyl CoA in the mitochondrial matrix
true
TRUE OR FALSE photons from light can boost an electron to a higher energy state
true
TRUE OR FALSE proteins and fats may be used as energy sources to drive aerobic respiration
true
TRUE OR FALSE temp, pH, and ionic concentrations each play an important role in the proper functioning of enzymes
true
TRUE OR FALSE the electron transport chain consists of a series of redox reactions in which electrons are transferred to oxygen as the final electron acceptor
true
TRUE OR FALSE when a molecule of NAD+ gains a hydrogen atom, the molecule becomes reduced
true
Mammals like caribou that live in the arctic often use different lipid types in their legs. Legs are more susceptible to heat loss than internal organs, which are closer to the body core and stay warmer. Which adaptations would you expect for lipids in caribou legs? The membranes would contain more cholesterol. (T/F)
true, (Cholesterol makes membranes more fluid at lower temperatures.)
Mammals like caribou that live in the arctic often use different lipid types in their legs. Legs are more susceptible to heat loss than internal organs, which are closer to the body core and stay warmer. Which adaptations would you expect for lipids in caribou legs? The lipids on the fatty acid tails would be shorter. (T/F)
true, (Shorter tails are more fluid at lower temperatures.)
Using your knowledge about the movement of molecules in and out of a cell, pair up the type of transportation mode to the most accurate description of its mechanism 1. symporter 2. uniporter 3. biporter 4. antiporter The movement of a single ion or molecule into or out of a cell
uniporter
The processes of active transport and facilitated diffusion both
use transport proteins to move material across the membranes.
The function of the enzyme ATP synthase is to...
utilize the energy of the proton motive force to convert ADP to ATP.
Osmosis is best defined as the movement of
water molecules across a membrane from an area of high water concentration to an area of lower concentration.
Erythrocytes from an isotonic blood transfusion are transferred to an individual with abnormally high sodium in the blood. The most likely impact on the erythrocytes in this transfusion is
water will diffuse out of the cell, causing the cells to crenate.
Solvent
water, Does the dissolving
In the process of diffusion, when sugar is mixed with water, equilibrium would be reached
when the dissolved sugar molecules are evenly distributed throughout the solution.