Which of the following are fossil plants? a. pterosaurs and plesiosaurs b. trilobites and eurypterids c. graptolites and archaeocyathids d. gymnosperms and angiosperms

The correct option is d)  gymnosperms and angiosperms

Explanation:

Gymnosperms can be described as plant species which do not produce flowers. These plant species produce cone and seeds instead of flowers.

Angiosperms can be described as the plants which produce flowers. These plant type comprises of eggs which when fertilized develop into seeds. Angiosperms are also known as flowering plants.

this protocol provides a detailed procedure for agarose-based ip to purify and enrich the protein of interest.

explanation:

b,bacteria convert nitrates

into nitrogen gas.

d,plants and animals take in

and use nitrogen compounds.

e,bacteria break down waste    

products and return nitrogen  

to the soil.

a,bacteria convert atmospheric

nitrogen to ammonia.

c,bacteria convert ammonia

to nitrites and nitrates.