In human beings, sex is determined by:

How is the sex of a newborn in humans determined?

What is the probability percentage of a zygote developing into a male or female offspring in humans?

Why did Mendel choose the pea plant $(Pisum \text{ } sativum)$ for his experiments?

In dogs, the barking trait is dominant over the silent trait and erect ears are dominant over drooping ears. Now, find out
$(i)$ What is the expected phenotypic ratio of the offspring when dogs, heterozygous for both the traits are crossed?
$(ii)$ What are different phenotypes observed?
$(iii)$ What is this type of cross known as?

Which radioactive element (isotope) is used to determine the age of fossils?