bio test #3

NAD and FAD

Both the NAD and FAD are both electron carriers.Main difference seen between the two is in accepting the hydrogen atoms. ... NAD is reduced to NADH in CItric Acid Cycle and glycolysis,it then transfers electrons into electron transport chain at Complex 1.Hence helps produce 3 ATPs for every NADH

What challenge does C. ruddii present to our understanding of what constitutes a cell (see Figure 8.9)?

It is not clear when a cell evolves into an organelle or a symbiont.

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.

Figure 7.16 reveals how new membrane tubes are produced inside cells. Which cellular process was revealed by these data?

Membranes are pulled by protein motors on protein tracks.

Which of the following statements accurately describes wavy plasma membrane surfaces?

Lipid composition can determine membrane shape and luminal diameter.

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.ATP 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

Following glycolysis and the citric acid cycle, _______ and _________ account for most of the energy extracted from glucose.

NADH and FADH2

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 8.10 contains the first published images of a completely new type of organism called nanobacteria. What was the final conclusion about nanobacteria?

Nanobacteria are not real, they are chemical crystals.

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 mistake did the investigators make when they discovered E. fishelsoni shown in Figure 8.6?

They mistakenly thought this was a eukaryote rather than a bacterium.

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

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.

adenylyl cyclase production of cAMP covalent modulation of phosphorylase kinase protein kinase A activation activated receptor activating the G protein

Phosphorylation cascades involving a series of protein kinases are useful for cellular signal transduction because they ________.

amplify the original signal many times

What is beta oxidation

beta-oxidation is the catabolic process by which fatty acid molecules are broken down in the cytosol in prokaryotes and in the mitochondria in eukaryotes to generate energy

Use the Figure of the mitochondrial membrane to determine which of the following statements are correct. question 7 2nd chapter 10 quiz

complex IV is oxidized when it donates electrons to oxygen. Complex I is reduced when it accepts electrons from NADH. Oxygen is required for H+ movement.

Deamination is ___________ by GTP.

inhibited

Oxygen consumption takes place ______.

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

When ATP is converted to ADP + inorganic phosphate releasing 32 kj/mole of energy, the change in free energy (deltaG) is

negative

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

The coenzyme shown in the figure above is in the________state and would __________ electrons to/from the substrate. chapter 10 first quiz #6

oxidized; accept

How many of the 20 amino acids can be covalently modified by kinases?

serine, threonine, and tyrosine

What catalyzes the peptide bond formation

the ribsome

Viruses can have double-stranded RNA genomes.

true

Viruses can maintain internal environments that differ from their external environments.

true

does Converting ATP to ADP release energy

yes, breaks a phosphoanhydride bond

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

When you respond to fear, the cellular response in your liver cells includes (select all that apply)

enzyme activation covalent modulation signal amplification enzyme inhibition allosteric modulation feedback regulation

All bacteria reproduce by binary fission.

false

Since cells are 70% water the rate of diffusion of a molecule is 70% of its rate in pure water.

false

Symbionts will have smaller genomes than free-living organisms.

false

The more virulent a viruses are correlated positively with large genomes size.

false

The same enzyme can be used for any fatty acid substrate.

false

Viral genomes can be identified because they are smaller than bacterial genomes

false

The major concept of biology that we are focusing on that is linked to the study of the transformation of energy is

homeostasis

ATP is __________ to ADP + inorganic phosphate releasing 32 kj/mole of energy.

hydrolyzed

Is epinephrine hydrophobic or hydrophilic?

hydrophilic

The amino acid that is phosphorylated by PKA is Serine. Which of the following -R groups will allow for this reaction?

-OH hydroxyl

Approximately how much distance would there be between two molecules if there were 100 inside E. coli? figure 8.17

200 nm

What is the advantage of using oxygen as an electron acceptor?

A major advantage of aerobic respiration is the amount of energy it releases

What is the effect of allosterically regulated enzymes

Allosteric enzyme regulation is where a molecule binds an allosteric site, altering enzyme conformation and thereby activating or deactivating the enzyme, or increasing and decreasing its activity.

Which is the following is the most important difference between covalent and allosteric modulation of proteins?

Allosteric modulation requires a phosphatase and covalent modulation requires a kinase.

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. A According to the data shown in these graphs, the enzyme GDH is allosterically activated by __________. Select all that apply.

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

What is the purpose of coenzymes

Coenzymes, in turn, support the functions of enzymes. They loosely bind to enzymes to help them complete their activities

covalent modulation

Covalent modulation, however, is much more durable and is typically removed only when an enzyme, such as a phosphatase, breaks the bond holding the phosphate in place.

entropy

Entropy, the measure of a system's thermal energy per unit temperature that is unavailable for doing useful work. Because work is obtained from ordered molecular motion, the amount of entropy is also a measure of the molecular disorder, or randomness, of a system.

All bacteria are smaller than eukaryotes.

False

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.

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.

What makes a phosphate group inorganic

Inorganic phosphates can be created by the hydrolysis of pyrophosphate.

pyruvate

Organic compound with a backbone of three carbon atoms. Two molecules form as end products of glycolysis

What is the difference between aerobic and anaerobic respiration? How do we switch from one to the other?

Summary. Aerobic respiration is far more energy-efficient than anaerobic respiration. Aerobic processes produce up to 38 ATP per glucose. Anaerobic processes yield only 2 ATP per glucose

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.

Stanley Prusiner won a Nobel Prize for his work with prions. What was so unusual about prions?

They are the only infectious substances that lack nucleic acids.

What role do phosphatases play in signal transduction pathways?

They inactivate protein kinases to turn off signal transduction

what is a secoundary structure

With this first layer of folding, some characteristic shapes become apparent and are called secondary structures (Figure 7.1B). Spiral alpha helices and zigzagging beta strands form as a result of weak H-bonds between the universal backbones of amino acids aligned in just the right pattern due to the chemical properties of their side chains.

The molecule shown above is __________. (Select all that correctly complete the sentence.) coenzyne a

a coenzyme important for transferring 2 carbon molecules to the mitochondria required for the oxidation of fatty acids a modified inucleotide

Protein kinase is an enzyme that functions in which of the following ways?

activates or inactivates other proteins by adding a phosphate group to them

Kinase activity

can either activate or inhibit reactions.

How does energy come out of amino acids

can have their amino groups removed and then the remainder of the molecule can be oxidized to provide energy. ... Some amino acids are converted to pyruvate or pyruvic acid. Some are converted into acetyl CoA.

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

The primary reason cells are small, even in large organisms, is...?

diffusion of cell components would be too slow in a large cell.

The regulation of glycolysis occors on the enzyme phosphofructose kinase (PFK). Which of the following molecules would inhibit this enzyme?

large concentrations of ATP relative to ADP

Where does beta oxidation take place?

mitochondria

FRAP is a method that measures which physical properties of cells?

percent mobile proteins and their rate of movement

If you feed your experimental canine subjects a high dose of a fatty acid with 24 carbons in the chain, 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

Describe what a kinase does and the protein that performs the opposite function

phosphorylates a protein by attaching a phosphate to protein

What does glycolysis produce?

produces energy in the form of ATP, NADH, and pyruvate, which itself enters the citric acid cycle to produce more energy.

third and fourth structures

structure. New folds, hydrophobic interactions, as well as ionic and hydrogen bonds will form, producing the tertiary structure, which is the overall three-dimensional shape of the protein. If a protein assembles with two or more proteins, then the collection of proteins accumulates quaternary structure, which is the result of the individual proteins interacting based on their already established tertiary structure. Every protein contains primary, secondary, and tertiary structure, and some will form quaternary structure

The main regulation of Beta-oxidation is

the availability of CoA.

Glycolysis

the breakdown of glucose by enzymes, releasing energy and pyruvic acid.

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

The catabolic reactions that breakdown fatty acids and proteins are similar in that

they result in 2 carbon molecules

What is signal transduction?

transmission of molecular signals from a cell's exterior to its interior

primary structure of amino acid sequence is sufficient information for proteins to take their final three dimensional shapes.

what does the primary structure provide