After geographic separation, what process would be the last step before reproductive isolation?

The origin of a new plant species by hybridization, coupled with accidents during cell division, is an example of

Which of the following statements about species, as defined by the biological species concept, is (are) correct? I. Biological species are defined by reproductive isolation. II. Biological species are the models used for grouping extinct forms of life. III. The biological species is the largest unit of population in which successful interbreeding is possible.

Which of the following statements about speciation is correct?

The phylogenetic species concept defines a species as

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

The major evolutionary episode corresponding most closely in time with the formation of Pangaea was the

In a synthetic biology experiment, you are given a task to design a new species of aquatic protist. Your design should account for the following characteristics: 1. The protist functions as a primary producer. 2. It cannot swim on its own. 3. It must stay in well-lit surface waters. 4. It must be resistant to physical damage from wave action. Based on these criteria, you decide to model your creation after a(n)

All protists are

Multicellular colonies of plant cells adhere to each other primarily by ________, whereas multicellular colonies of animal cells are typically held together by ________.