Look at the age-structure pyramids. the numbers between the bars (in the middle of the graphs) serve as the y-axis. what do these numbers represent? a. the population of males and females
b. the age classes, in 5-year ranges
c. the total population, in millions
d. the number of people born in a particular year
e. the percentage of the population in each age class

The answer is B. the age classes, in 5-year ranges

Explanation:

Age structure pyramid, also called an age-sex- pyramid, is a graphical illustration that shows the distribution of various age groups in a population. It is often viewed as the most effective way to graphically depict the age and distribution of a population.

It contains continuous bars stacked on top of another with each representing an age category, making it a horizontal bar diagram. The horizontal length which is the x-axis represent the number of individuals while the age-groups are represented on the y-axis (vertical or central). The age group are the same size to maintain proportionality.

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.