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TLS Online TPP Program

#Question id: 2159

A channel protein

#SCPH28 | Zoology

  1. moves ions at a rate similar to that of a transporter.

  2. can be open at all times.  

  3. can move ions up an electrochemical gradient.

  4. generally moves both anions and cations through the same channel.

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TLS Online TPP Program

#Question id: 12570

#SCPH06 I Botany

Extinction is a natural phenomenon. It is estimated that 99% of all species that ever lived are now extinct. Why then do we say that we are now in a biodiversity crisis?
TLS Online TPP Program

#Question id: 10519

#SCPH05 I Biotechnology

Which of the following toxins derived from the fungus Cochliobolus carbonum inhibits specific histone deacetylases in maize?
TLS Online TPP Program

#Question id: 1606

#I Life Science/ Life Sciences Group – I-V

transporter associated with antigen processing(TAP) is ,
TLS Online TPP Program

#Question id: 7309

#I Life Science/ Life Sciences Group – I-V

Following statements are regarding to the molecular basis of the coincidence model in Arabidopsis.

A. In Arabidopsis under short days, there is little overlap between CO mRNA expression and daylight.

B. CO protein does not accumulate to sufficient levels in the phloem to promote the expression of the transmissible floral stimulus and the plant remains vegetative.

C. Under long days, the peak of CO mRNA abundance (at hours 12 through 16) overlaps with daylight (sensed by phyA and cryptochrome [cry]), allowing CO protein to accumulate.

D. CO activates FLC mRNA expression in the phloem, which causes flowering when the FT protein is translocated to the apical meristem.

Which of the following is incorrect?
TLS Online TPP Program

#Question id: 15152

#SCPH12 I Genetics

In this problem we will explore some of the many ways that mutations in two different genes can interact to produce different Mendelian ratios. Consider a hypothetical insect species that has red eyes. Imagine mutations in two different unlinked genes that can, in certain combinations, block the formation of red eye pigment yielding mutants with white eyes. In principle, there are two different possible arrangements for two biochemical steps responsible for the formation of red eye pigment. The two genes might act in series such that a mutation in either gene would block the formation of red pigment. Alternatively, the two genes could act in parallel such that mutations in both genes would be required to block the formation of red pigment.
Further complexity arises from the possibility that mutations in either gene that lead to a block in enzymatic activity could be either dominant or recessive. If the crosses is made between a wild type insect with red eyes and a true breeding white eyed strain with mutations in both genes. Such considerations yield the Pathways in series with dominant mutations in both genes, determine the phenotype of the F1 progeny and the expected phenotypic ratio of red to white eyed insects in the F2.