Exam #4 BIO
The molecule shown above is __________. (Select all that correctly complete the sentence.)
-a coenzyme important for transferring 2 carbon molecules to the mitochondria -required for the oxidation of fatty acids The
Figure 11.2 illustrates one of the very first experiments to understand what we now call photosynthesis. What controls are missing from this figure? (select all that apply)
-the same setup but kept in the dark -the same setup but no plant sprig
The catabolic reactions that breakdown fatty acids and proteins are similar in that
-they result in 2 carbon molecules -the use availability of coenzymes for regulation
Non-cyclic electron flow requires (Select all that apply)
-water -photosystem II -NADP+ -light -photosystem I
The same enzyme can be used for any fatty acid substrate.
False
When ATP releases some energy, it also releases inorganic phosphate. What happens to the inorganic phosphate in the cell?
It may be used to form a phosphorylated intermediate.
Which of the amino acids in the figure above have hydrophilic R groups? Select all that apply.
Look for OH side chains
The data presented in the figure above supports which of the following statements?
Fixed CO2 is first incorporated into simple sugars that can then be used to synthesize a diversity of macromolecules.
Once six 3-carbon sugars accumulate, chloroplasts harvest 1 and use the other 5 to produce 3 copies of ribulose bisphosphate again.
True
What is the difference between secondary and tertiary protein structure?
Secondary structures come in only two shapes whereas tertiary structures results in many diverse shapes.
What evidence did Krebs use to deduce the cyclic nature of the citric acid cycle?
added acid #8 and acids #1 and #4 accumulated.
Which of the following is a common example of covalent modulation of a protein?
addition of a phosphate group
Phosphorylation cascades involving a series of protein kinases are useful for cellular signal transduction because they _______.
amplify the original signal many times
The activity of rubisco is dependent on pH and Mg++ concentration. Which of the following describes this relationship? Rubisco activity of 50 nmol min-1 mg -1 occurs
at pH 8 and 20 mM Mg++
Due to the requirement for more ATP in the Calvin cycle, brighter sunlight (blue wavelength) that is available during the day are predominantly associated with ___________ whereas the morning sun (red wavelengths) are associated with _______
cyclic electron flow; non-cyclic
Deamination is ___________ by GTP.
inhibited
oxygen consumption takes place in the _____
inside the mitochondria
The amount of energy in the carbon dioxide and water produced from burning wood is _______ the amount of energy that was originally in the wood.
less than
What is a good working definition for homeostasis?
maintain internal conditions within a range of acceptable extremes
After wood is burned, carbon dioxide and water are formed. These products have _____ entropy than the wood.
more
When ATP is converted to ADP + inorganic phosphate releasing 32 kj/mole of energy, the change in free energy (deltaG) is
negative
The coenzyme shown in the figure above is in the________state and would __________ electrons to/from the substrate.
oxidized; accept
The 3 processes of photosynthesis are regulated by ____________
separate processes
According to the data in Figure 11.5.....
there is about a 10 fold difference in H+ between the stroma and the thylakoid space.
Imagine a Bird of Paradise jumping around and actively cleaning its"dance" area. The energy that is used to do all of this work is stored in the cell as
electrons in covalent bonds
Which of the following study methods is LEAST likely to lead to understanding core concepts and retaining the information longer.
focusing on many aspects, especially the details
Which of the following graphs most likely describes the effect of pH on the function of the enzyme catalase in human cells? Note: The x-axis is pH and the y-axis is enzyme activity.
hill
The major concept of biology that we are focusing on that is linked to the study of the transformation of energy is
homeostasis
Plants capture the energy in light and produce what form of potential energy that will be used to produce ATP?
hydrogen ion accumulation in thylakoid space
ATP is __________ to ADP + inorganic phosphate releasing 32 kj/mole of energy.
hydrolyzed
The process of Cyclic electron flow utilizes (Select all that apply).
-Photosystem I -light -electron transport chain molecules
Which of the following are common to the metabolic degradation of fatty acids, proteins, and sugars? (select all that apply)
-NADH is produced that can be fed to the electron transport chain. -a 2 carbon molecule is produced that can be fed to the Citric Acid cycle
Figure 12.9 are experimental results that reveal what chemical signals guard cells use to regulate stomata opening. Which statements are consistent with the data? (select all that apply)
-NO alone can cause stomata to close.. -ABA plus NO scavenger is significantly more open than ABA alone.
Cyclic and non-cyclic (linear) electron flow during photosynthesis differ in what ways? (select all that apply)
-Non-cyclic produces NADPH whereas cyclic does not produce NADPH. -Non-cyclic requires the splitting of water to continue whereas cyclic does not.
The amino acid that is phosphorylated by PKA is Serine. Which of the following -R groups will allow for this reaction?
-OH hydroxyl
3 main steps of photosynthesis
-split water -harvest electrons and make ATP -Fix carbon
Figure 11.15 shows the results of experiments testing how rubisco functions under different physiological conditions. How do these data relate to the homeostasis of carbon fixation? (select all that apply)
-The light reaction generates a rise in stromal Mg2+ to counter balance the loss of H+ ions. -Rubisco works best when the chloroplast is actively producing the pH gradient.
Figure 11.5 measures the pH in various compartments inside the chloroplasts. Which of the statements below are supported by the experimental data? (select all that apply)
-The pH gradient generated by light takes about as long to generate as it does to dissipate. -Light generates a H+ ion gradient that is more than 100 fold different across the thylakoid membrane. -Light causes H+ ions to move from the stroma to the thylakoid space.
Figure 7.5 shows the major steps in the response to epinephrine. Which of the following steps shows amplification of the signal? Select all that apply.
-activated receptor activating the G protein -covalent modulation of phosphorylase kinase -adenylyl cyclase production of cAMP -protein kinase A activation
What happens during a redox reaction? Select all that apply.
-new covalent bonds are formed -a chemical is reduced -electrons are transferred from one chemical to another -a chemical is oxidized
When you respond to fear, the cellular response in your liver cells includes (select all that apply)
-signal amplification -enzyme activation -enzyme inhibition -feedback regulation -allosteric modulation -covalent modulation
Figure 10.12 B, GDH (Glutamate Dehydrogenase) activity is modulated by ATP and ADP over a range of NADH concentrations. The ratio of activity compares GDH with and without the indicated nucleotide. C, GTP and ATP alter GDH activity differently at 85 µM NADH. According to the data shown in these graphs, the enzyme GDH is allosterically activated by __________. Select all that apply. ADP
ADP
A major take away from this summary diagram is ______.
ATP is a major inhibitor of cell respiration.
The catalytic domains of Protein Kinase A use _________ to __________ other proteins.
ATP; phosphorylase
A 4 year old girl died after giving her dog a bath with a product called FleaDip. Doctors administered oxygen but were unable to revive her.The autopsy report listed these levels of metabolites in the heart cells.Metabolite Autopsy finding Normal Levels Glucose102 nmol100 nmolPyruvate23 mmol25 mmolNAD+6 mmol75 mmolNADH383 mmol50 mmolATP levels were also reduced in the mitochondria, however the cytoplasmic levels were normal. Acetyl-CoA levels were also normal.These data best support which of the following conclusions?
Complex I of the electron transport chain is blocked
Which is the following is the most important difference between covalent and allosteric modulation of proteins?
Covalent modulation includes the transfer of functional groups like phosphates to reactive R groups on specific amino acids.
Figure 10.7 shows some of the artificial lipids that were produced in order to determine how fatty acids were oxidized to extract energy during digestion. What conclusion was reached based on this experiment? Select all that apply.
Fatty acids are broken down by always removing two carbons at a time.
Which of the following sequences correctly represents the flow of electrons during photosynthesis?
H2O → NADPH → Calvin cycle
Explain why starch is rich in calories for a human, but cellulose is not.
Human enzymes can bind to and break α 1-4 bonds but not β 1-4 bonds.
Following glycolysis and the citric acid cycle, _______ and _________ account for most of the energy extracted from glucose.
NADH and FADH2
In autumn, chlorophyll is degraded in the leaves of deciduous trees. Why do the leaves change color to shades of yellow, orange, or red?
Other pigments such as carotenoids are still present in the leaves.
Biological systems use free energy based on empirical data that all organisms require a constant energy input. The first law of thermodynamics states that energy can be neither created nor destroyed. For living organisms, which of the following statements is an important consequence of this first law?
The organism must ultimately obtain all the necessary energy for life from its environment.
What is the relationship between the wavelength of light and the quantity of energy per photon?
They are inversely related.
Protein kinase is an enzyme that functions in which of the following ways?
They inactivate protein kinases to turn off signal transduction.
Why type of molecule is the first to be formed by plants during carbon fixation as shown in Figure 11.13?
carbohydrates
Which of the following molecules is likely to have the most potential energy?
casein
On of the main rules seen in biology is "change in structure- ____________"
change in function
Reaction center chlorophyll molecules, __________.
donate electrons to the electron transport chain
The regulation of glycolysis occurs on the enzyme phosphofructokinase (PFK). Which of the following molecules would inhibit this enzyme?
large concentrations of ATP relative to ADP
If you feed your experimental canine subjects a high dose of a fatty acid with 24 carbons in the chain connected to the benzene ring as shown above, which of the molecules shown in the figure above would be found in dog's urine after time for complete metabolic digestion to take place?
phenylacetic acid
The ability to split water into H+, e-, and O2 is a function of
photosystem II (P680)
The main regulation of Beta-oxidation is
the availability of CoA.
Figure B graphs the pH of the matrix before and after adding a H+ ion channel that allows the protons to flow. Use figure B to compare the H+ concentration of the matrix of the mitochondria relative to the cytoplasm before the drug was added.
the matrix has fewer H+ ions
Antenna complexes are located in the
thylakoid membranes