With respect to X-chromosome inactivation, which, if any, of the following statements are not correct? 

I. X-chromosome inactivation in mammals begins in the pre-implantation embryo 

II. In humans all diploid cells that carry two normal X-chromosomes are subject to a random pattern of X-inactivation. 

III. Once a decision has been made to inactivate an X chromosome (either the paternal or maternal X), all descendant cells show the same pattern of X-inactivation. 

IV. The inactivated X chromosome becomes a highly condensed Barr body in which genes are silenced across the length of the chromosome.

TLS Online TPP Program

#Question id: 33361

#Unit 1. Molecules and their Interaction Relevant to Biology

a. Hb Cowtown: eliminates an ion pair involved in T-state stabilization

b. Hb Milwaukee: substitutes a Glu for a Val

c. Hb Providence: substitutes an Asn for a Lys that normally projects into the central cavity of the tetramer

d. Hb Philly: substitutes a Phe for a Tyr,

Which Hb variant will not bind to BPG

TLS Online TPP Program

#Question id: 33362

#Unit 1. Molecules and their Interaction Relevant to Biology

a. Hb Cowtown: eliminates an ion pair involved in T-state stabilization

b. Hb Milwaukee: substitutes a Glu for a Val

c. Hb Providence: substitutes an Asn for a Lys that normally projects into the central cavity of the tetramer

d. Hb Philly: substitutes a Phe for a Tyr

Which Hb variant will have changed pI as compared to HbA

TLS Online TPP Program

#Question id: 33363

#Unit 1. Molecules and their Interaction Relevant to Biology

An antibody binds to an antigen with a Kd of 5 X10^-8 M. At what concentration of antigen will θ be 0.2

TLS Online TPP Program

#Question id: 33364

#Unit 1. Molecules and their Interaction Relevant to Biology

An antibody binds to an antigen with a Kd of 5 X10^-8 M. At what concentration of antigen will θ be 0.5

TLS Online TPP Program

#Question id: 33365

#Unit 1. Molecules and their Interaction Relevant to Biology

An antibody binds to an antigen with a Kd of 5 X10^-8 M. At what concentration of antigen will θ be 0.6

TLS Online TPP Program

#Question id: 33366

#Unit 1. Molecules and their Interaction Relevant to Biology

An antibody binds to an antigen with a Kd of 5 X10^-8 M. At what concentration of antigen will θ be 0.8