Filters
Question type

Study Flashcards

Mammals and other animals have a circulatory system because diffusion is to slow to supply the tissues with oxygen in animals that are larger than 2 millimeter.Explain in one sentence why these circulatory systems contain hemoglobin or other oxygen binding proteins?

Correct Answer

verifed

verified

Oxygen-binding proteins increa...

View Answer

The Hill plot shows that the fourth oxygen binds to hemoglobin with a ______-fold greater affinity than the first.


A) 2
B) 5
C) 10
D) 20
E) 100

Correct Answer

verifed

verified

Matching -Mutations that favor the oxidation of the heme iron(II) to iron(III) can cause ______.


A) positively cooperative
B) cyanosis
C) His E7
D) decrease
E) R
F) hydrogen bonds
G) increase
H) symmetry
I) His F8
J) ion pairs
K) T
L) hemolytic anemia
M) sequencial

Correct Answer

verifed

verified

Which class of antibodies has been implicated in allergic reactions?


A) IgA
B) IgD
C) IgE
D) IgG
E) IgM

Correct Answer

verifed

verified

______of the world's human population carries an inherited variant hemoglobin gene.


A) 5%
B) 25%
C) 50%
D) 75%
E) 90%

Correct Answer

verifed

verified

C

The Ig fold can be described as a


A) globular fold composed of α\alpha helices.
B) a globular fold composed of a four helix bundle.
C) a globular fold composed of a β\beta sandwich.
D) a globular fold composed of β\beta barrel.
E) a coiled-coil.

Correct Answer

verifed

verified

You have been studying O2 binding to a hemerythrin-like protein isolated from an exotic marine worm.Your O2-binding data are shown in the table below. a.Use the data to generate an O2-binding curve (do not forget to mark the axes). b.Use the curve to estimate the Kd for the interaction. c.Is there any evidence from your data that this hemoglobin-like protein binds O2 in a cooperative manner (briefly explain your answer)? You have been studying O<sub>2</sub> binding to a hemerythrin-like protein isolated from an exotic marine worm.Your O<sub>2</sub>-binding data are shown in the table below. a.Use the data to generate an O<sub>2</sub>-binding curve (do not forget to mark the axes). b.Use the curve to estimate the K<sub>d</sub> for the interaction. c.Is there any evidence from your data that this hemoglobin-like protein binds O<sub>2</sub> in a cooperative manner (briefly explain your answer)?       You have been studying O<sub>2</sub> binding to a hemerythrin-like protein isolated from an exotic marine worm.Your O<sub>2</sub>-binding data are shown in the table below. a.Use the data to generate an O<sub>2</sub>-binding curve (do not forget to mark the axes). b.Use the curve to estimate the K<sub>d</sub> for the interaction. c.Is there any evidence from your data that this hemoglobin-like protein binds O<sub>2</sub> in a cooperative manner (briefly explain your answer)?

Correct Answer

verifed

verified

a.see curve blured image
b.see curve,Kd eq...

View Answer

Myoglobin's primary physiological role is to facilitate oxygen ________.


A) storage
B) metabolism
C) binding
D) reduction
E) diffusion

Correct Answer

verifed

verified

The energy needed to drive muscle contraction comes from ATP hydrolysis that is carried out by


A) G-actin.
B) F-actin.
C) myosin heads.
D) myosin tails.
E) tropomyosin.

Correct Answer

verifed

verified

Fab fragments can be generated by


A) reduction of IgG molecules.
B) oxidation of IgG molecules.
C) limited digestion of IgG molecules with papain.
D) combining two light chains.
E) combining two heavy chains.

Correct Answer

verifed

verified

Muscle contraction is triggered


A) in response to an increase in the cytoplasmic Ca2+ concentration.
B) in response to a decrease in the cytoplasmic Ca2+ concentration.
C) in response to an increase in the cytoplasmic cAMP concentration.
D) in response to a decrease in the cytoplasmic cAMP concentration.
E) in response to an increase in the cytoplasmic titin concentration.

Correct Answer

verifed

verified

A

When the partial pressure of O2 in venous blood is 30 torr,the saturation of myoglobin with O2 is ______ while the saturation of hemoglobin with O2 is ______.


A) 0) 55,0.91
B) 0) 91,0.55
C) 2) 8 torr,26 torr
D) 0) 91,0.97
E) none of the above

Correct Answer

verifed

verified

Which statement about actin is not true?


A) There are two actin genes,one for F-actin and one for G-actin.
B) Monomeric G-actin polymerizes to form F-actin.
C) Actin filaments are polar (the ends can be distinguished)
D) Actin can bind ATP.
E) Actin is a common protein in nonmuscle cells.

Correct Answer

verifed

verified

The rearrangement of T state hemoglobin to the R state


A) occurs in each protein subunit independently when its heme binds oxygen.
B) requires the binding of at least three oxygen molecules.
C) increases the ion pairing interactions of the C-terminal amino acids.
D) involves the movement of the Fe(II) into the heme plane.
E) opens a central cavity for BPG binding.

Correct Answer

verifed

verified

Matching -The absence of 2,3-BPG causes hemoglobin's affinity for oxygen to______.


A) positively cooperative
B) cyanosis
C) His E7
D) decrease
E) R
F) hydrogen bonds
G) increase
H) symmetry
I) His F8
J) ion pairs
K) T
L) hemolytic anemia
M) sequencial

Correct Answer

verifed

verified

G

Which of the following statements does not apply to the K value in the equation for the oxygen binding curve of myoglobin?


A) It is numerically equal to p50.
B) It is defined as that oxygen partial pressure at which half of the oxygen binding sites are occupied.
C) It is a measure of the affinity of myoglobin for oxygen.
D) If Y > K,then myoglobin is less than 50% saturated with oxygen.
E) It is the value of pO2 at which Y = 0.5.

Correct Answer

verifed

verified

Which statement about myosin is not true?


A) Myosin is a heterohexamer.
B) Myosin contains two globular heads.
C) Myosin contains six different polypeptides
D) Myosin aggregates to form thick filaments
E) All of the answers above are true of myosin.

Correct Answer

verifed

verified

Myoglobin is an oxygen binding protein in muscle.Describe in one sentence the overall structure of myoglobin.

Correct Answer

verifed

verified

Myoglobin is a globular protei...

View Answer

During the T to R conformational shift,Fe(II) drags the F-helix via a bond to the side chain of ________.


A) Leu F7
B) Leu F4
C) His F8
D) Leu FG3
E) Val FG5

Correct Answer

verifed

verified

The most rapid way that erythrocytes adapt to high altitudes is


A) by producing genetically altered hemoglobins that have higher O2-binding affinities.
B) by adopting the symmetry model of allosterism.
C) by increasing the concentration of hemoglobin.
D) by relying upon the simpler protein myoglobin.
E) by increasing the intracellular concentration of BPG.

Correct Answer

verifed

verified

Showing 1 - 20 of 74

Related Exams

Show Answer