Question

Jurassic period of the Mesozoic era is characterised where
(A) flowering plants and first dinosaur appeared
(B) Gymnosperms are dominant plants and first birds appear
(C) Radiation of reptiles and origin of mammal-like reptiles
(D) dinosaur became extinct and angiosperms appeared

Answer 1

Hint: The second section of the Mesozoic Era was the Jurassic Period. It existed between 199.6 and 145.5 million years ago, after the Triassic period and before the Cretaceous period. The Jurassic period is the middle period of the Mesozoic era, also known as the Age of Reptiles.

Complete Answer:
- On earth, the habitats were dominated by dinosaurs and flying pterosaurs, and birds made their first appearance. There were also early mammals, but they were also somewhat insignificant. Insect species were diverse and gymnosperms dominated the plants.
- By the Mesozoic Period, the ability to survive on land rather than being limited to the seas had emerged from living creatures. At the beginning of the Jurassic, bryophytes, the low-growing mosses and liverworts that lacked vascular tissue and were limited to swampy wet areas, had developed plant life. A modern method of plant reproduction arose during the Jurassic.
- Gymnosperms, cone-bearing plants such as conifers, have allowed pollen to be spread by wind. This bisexual reproduction allowed greater genetic combination and gymnosperms were widespread by the end of the Jurassic. Until the Cretaceous, genuine flowering plants did not grow.
- In the late Jurassic, the first known bird, Archaeopteryx, flew into the sky. Quite possibly, they originated from an early dinosaur coelurosaur. Archaeopteryx had to contend with pterosaurs for airspace that were the flying dinosaurs who had been buzzing in the skies. Dinosaurs from the Jurassic Period were some of the largest creatures ever to exist. Reptiles were also capable of laying amniotic eggs which during gestation, kept the growing young moist and nourished.

So the answer is option B.

Note: Reptiles were the dominant animal life forms during the Jurassic Period, as Steven Spielberg's 1993 film 'Jurassic Park' asserts. Reptiles had solid ossified skeletons that were provided by sophisticated body support and locomotion muscle systems.