In a given population, 128 out of every 400 people has a carrier for recessive allele b that caused cancer in homozygous condition,  Assuming the population is in Hardy- Weinberg equilibrium, which of the following is the expected frequency of allele B and b in population respectively?

#Question id: 2200

#Unit 2. Cellular Organization

A neurotransmitter that binds to a postsynaptic cell and opens K+ channels:

#Question id: 2201

#Unit 2. Cellular Organization

Much of what we know about the nicotinic acetylcholine receptor has come from studies of:

#Question id: 2202

#Unit 2. Cellular Organization

The distribution of K⁺ across an artificial membrane was measured, and the concentrations were found to be equal on both sides. Which of the following statements is true about the distribution of K⁺?

#Question id: 2203

#Unit 2. Cellular Organization

Parietal cells acidify the stomach contents while maintaining a neutral cytosolic pH by: 

a. exporting “excess” cytosolic OH– as HCO3–.
b. exchanging HCO3– for Cl–.
c. preserving electroneutrality by accompanying the movement of each Cl– ion into the stomach lumen by a K+.
d. the excess K+ ions pumped inward by the H+/K+ ATPase are returned to the stomach lumen, thus maintaining the normal intracellular K+ concentration.
Which of the following combination is correct?

#Question id: 2204

#Unit 2. Cellular Organization

A mutant channel protein is expressed in an oocyte. Compared to patch clamping experiments in oocytes expressing the normal channel, the length of downward deviations is diminished by half. This indicates:

#Question id: 2205

#Unit 2. Cellular Organization

Amino acid entry into cells can occur via uniporters or symporters. If the rate of leucine entry into the cell increases when the pH decreases, this suggests: