Which of the following statements is true? (a) extracellular signal molecules that are hydrophilic must bind to a cell-surface receptor so as to signal a target cell to change its behavior. (b) to function, all extracellular signal molecules must be transported by their receptor across the plasma membrane into the cytosol. (c) a cell-surface receptor capable of binding only one type of signal molecule can mediate only one kind of cell response. (d) any foreign substance that binds to a receptor for a normal signal molecule will always induce the same response that is produced by that signal molecule on the same cell type.

Its option 'A'.

Explanation:

extracellular signal molecules that are hydrophilic must bind to a cell-surface receptor so as to signal a target cell to change its behavior.

For Example:

Acetylcholine acts at a GPCR on heart muscle to make the heart beat more slowly.

chordata is the answer

tsd is temerature dependent sex determination.

tsd: it is a type of environmental sex determination in which the temperature experienced during embryonic/ larval development (ambient temperature for development) determine the sex of the offspring.

crocodile displays the tsd where the ambient temperature of the developing egg determines the individual's sex. for example in the american alligator's eggs, incubation at 33 ºc produces mostly males, while incubation at 30 ºc produces mostly females. so if the american alligator's egg will get the ambient temperature (33 degree celcius)during embryonic development from egg, the offspring will be male and same for the female sex determination.