You observed the two species of barnacles, species 1 and species 2, occupy upper and lower strata of intertidal rocks, respectively. Only when species 1 was removed by you from the upper strata, species 2 could occupy both the upper and lower strata. From the choice given below what would be your inference from these observations.

#Question id: 4973

#SCPH06 I Botany

Fossils of Lystrosaurus, a dicynodont therapsid, are most common in parts of modern-day South America, South Africa, Madagascar, India, South Australia, and Antarctica. It apparently lived in arid regions, and was mostly herbivorous. It originated during the mid-Permian period, survived the Permian extinction, and dwindled by the late Triassic, though there is evidence of a relict population in Australia during the Cretaceous. The dicynodonts had two large tusks, extending down from their upper jaws; the tusks were not used for food gathering, and in some species were limited to males. Food was gathered using an otherwise toothless beak. Judging from the fossil record, these pig-sized organisms were the most common mammal-like reptiles of the Permian.Which of Lystrosaurusʹ features help explain why these organisms fossilized so abundantly?

I. the presence of hard parts, such as tusks

II. its herbivorous diet

III. its persistence across at least two geological eras

IV. its widespread geographic distribution

V. its mixture of reptilian and mammalian features

#Question id: 1610

#SCPH05 I Biotechnology

A polymorphonuclear neutrophil (PMN):

#Question id: 22941

#SCPH06 I Botany

#Question id: 10708

#SCPH06 I Botany

Which of the following statements is a likely explanation for why invasive species take over communities into which they have been introduced?

#Question id: 1664

#I Life Science/ Life Sciences Group – I-V

A given Ig isotype is: