Myoglobin Fractional Saturation Flashcard

Front

Which of the following statements regarding the fractional saturation of myoglobin is FALSE?
It is a function of oxygen concentration.
It is a function of oxygen affinity.
It increases linearly at all oxygen concentrations.
The quantitative measure of oxygen affinity is determined at 50% saturation.

Back

It increases linearly at all oxygen concentrations.

Front

In the ___ form of Hb, the iron atom is out of the plane of the porphyrin ring.

Back

T

Front

Deoxyhemoglobin is unfavorable to oxygen binding because it is in the ____ conformation.

Back

T

Front

The Bohr effect describes a lowered O₂-affinity of hemoglobin (Hb) when the pH _____: increases, decreases, remains constant, fluctuates.

Back

decreases

Front

Which of the following would be an example of a conservative amino acid substitution? Gly replaced with Ser, Glu replaced with Gln, Arg replaced with Asn, Asp replaced with Glu

Back

Asp replaced with Glu

Front

Which of the following statements regarding the oxygen affinities of Mb and Hb is TRUE? The affinity of Mb remains high at all O₂ concentrations., The affinities of each of the 4 subunits of Hb are independent of each other., Hb exhibits different affinities at low versus high O₂ concentrations., Hb binds the first molecule of O₂ more readily than the last.

Back

Hb exhibits different affinities at low versus high O₂ concentrations.

Front

Would hemoglobin (Hb) bind O₂ with higher or lower affinity at pH 7.2 than it does at pH 7.4?

Back

Lower