#Question id: 4973
#Unit 11. Evolution and Behavior
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: 15443
#Unit 4. Cell Communication and Cell Signaling
#Question id: 534
#Unit 1. Molecules and their Interaction Relevant to Biology
If glucose labeled with 14C in C-3 is metabolized to lactate via fermentation, the lactate will contain 14C in:
#Question id: 7255
#Unit 5. Developmental Biology
The
hypostome acted as an “organizer” of the hydra. This notion has been confirmed
by:
A.
when transplanted, the hypostome can induce host tissue to form a second body
axis.
B.
the hypostome do not produces the head inhibition signal.
C.
the hypostome is the only “self-differentiating” region of the hydra.
D.
the hypostome produces a “head activation signal” that suppresses the formation
of new organizing centers.
Which one of the following combinations are incorrect?
#Question id: 7469
#General Aptitude