Question

Rocky Mountain juniper (Juniperus scopulorum) and one-seeded juniper (J. monosperma) have overlapping ranges. If pollen grains (which contain sperm cells) from one species are unable to germinate and make pollen tubes on female ovules (which contain egg cells) of the other species, then which of these terms are applicable?

1. sympatric species
2. prezygotic isolation
3. postzygotic isolation
4. allopatric species
5. habitat isolation
6. reduced hybrid fertility
A) 1 and 2B) 2 and 4C) 1, 3, and 6D) 2, 4, and 5E) 1, 2, 5, and 6

Answer 1

The applicable terms to describe the situation where pollen grains from one juniper species cannot fertilize the ovules of the other juniper species are prezygotic isolation and allopatric species.

Step-by-step explanation:

The applicable terms to describe the situation where pollen grains from one species are unable to germinate and make pollen tubes on the female ovules of the other species are prezygotic isolation and allopatric species.

Prezygotic isolation refers to the mechanisms that prevent fertilization from happening before the formation of a zygote. In this case, the pollen grains of one species are unable to successfully fertilize the female ovules of the other species, thus resulting in reproductive isolation.

Allopatric species, on the other hand, refers to species that are geographically separated and thus have limited or no contact with each other. In the scenario described, the two juniper species have overlapping ranges, indicating that they are not allopatric species.

Answer 2

The answer is A.

Step-by-step explanation:

The example given in the question is based on two plants that are from the same family but they can not reproduce even though they should be able to because they belong to the same family.

This situation is an example of the option given in A, Sympatric Species, which can be explained as two species that share the same habitats and live in the same geographical location evolves in different directions and after a point can not produce offspring from interbreeding and therefore should be considered as different species.

I hope this answer helps.