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TLS Online TPP Program

#Question id: 1374

Following statements are regarding to gap junctions.

i. Vertebrate gap junctions are composed of connexins, a family of structurally related transmembrane proteins with molecular weights between 26,000 and 60,000.

ii. Each vertebrate hexagonal particle consists of six noncovalently associated connexin molecules. Each individual connexin molecule has two membrane-spanning α helices with a topology similar to that of claudin.

iii. The permeability of gap junctions is regulated by posttranslational modification of connexins (e.g., phosphorylation) and is sensitive to changes in environmental conditions

such as intracellular pH and Ca2+ concentration, membrane potential, and the intercellular potential between adjacent interconnected cells (“voltage gating”).

iv. The assembly of connexins, their trafficking within cells, and the formation of functional gap junctions apparently depend on N-cadherin and its associated adapter proteins as well as desmosomal proteins.

Which of the following statements are correct?

#Unit 4. Cell Communication and Cell Signaling

  1. i, ii and iii

  2. i and iv

  3. i, iii and iv

  4. ii and iv

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TLS Online TPP Program

#Question id: 2465

#Unit 2. Cellular Organization

In the budding yeast S. cerevisiae, which of the following is NOT transported into the bud by myosin V?
TLS Online TPP Program

#Question id: 3908

#Unit 3. Fundamental Processes

Which of the following is correct?
TLS Online TPP Program

#Question id: 15745

#Unit 5. Developmental Biology

Which of the following protein acts synergistically with R-spondin1 (Rspo1)?
TLS Online TPP Program

#Question id: 12513

#Unit 7. System Physiology – Animal

A 26-year-old construction worker is brought to the emergency room with a change in mental status after working a 10-hour shift on a hot summer day (average outside temperature was 97°F). The man had been sweating profusely during the day but did not drink fluids. He has a fever of 102°F, heart rate of 140 beats/min, and blood pressure of 100/55 mm Hg in the supine position. On examination, he has no perspiration, appears to have dry mucous membranes, and is poorly oriented to person, place, and time. Assuming that his kidneys were normal yesterday, which of the following sets of hormone levels describes his condition, compared with normal?
TLS Online TPP Program

#Question id: 656

#Unit 1. Molecules and their Interaction Relevant to Biology

The ________ is the single shape a protein adopts under physiological conditions.