Assume that a single layer of phospholipids coat the water in a beaker. which part of the phospholipid molecule will face the air?
a. the phosphate groups
b. the hydrocarbon tails
c. the phospholipids would dissolve and not form a membrane coat
d. both heads and tails as the molecules are amphipathic and will lie sideways

The correct answer is-

b.the hydrocarbon tails.

A phospholipid molecule comprises of a head group (that contains polar phosphate molecule) that is hydrophilic ( water attracting groups due to formation of hydrogen bonding or ionic bonds with water molecules) and two tails of fatty acid ( which are hydrophobic that is water repelling groups).

In this question, a single layer of phospholipid coats the water in a beaker. This means that head group of this layer is in contact of water ( present in the beaker) and the two fatty acid tails of hydrocarbon ( that are water repelling) are facing air.

Thus, option b) is the right 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.