A polysome is . a. the complex that adds a poly(A) tail onto an mRNA b. an mRNA transcript to which multiple ribosomes are attached c. the combination of a large and a small ribosomal subunit d. the promoter assembly at the site of transcription initiation e. the complex where mRNA splicing occurs

b. an mRNA transcript to which multiple ribosomes are attached

Explanation: polysome consist of mRNA complex and two or more ribosome coming together to translate mRNA into a polypetide or amino acid. It helps produce many polypeptide from a single mRNA.

Different ribosomes bind to the mRNA at different time elongating the polypeptide chain. We have the free( non-poly A ) and memberane bound (poly A) polysome.

d concave shape of wave rock

explanation:

the concave shape of wave rock is a very good evidence that supports the evolution of earth due to chemical weathering. if we talk about structure of   wave rock, studies have estimated that it is around 2.7 billion years old. it also serves as the foundation of evidence that it was the place where australian continent began to form.

how the structure of wave rock was created?

studies suggest that structure of wave rock was created when the surrounded area was started to weather due to which deposition of material started on the part of land which now contains wave rock.

the structure of wave rock is considered to be one of the best-known landforms in australia. at the height of around 15 cm, there can be found flared slopes which formulate the margins of hyden rock. it is now assumed by geologists that wave rock was created by subsurface water-induced weathering and not by glaciers, waves or wind.

due to deposition of material over the period of long time, the wave rock became tougher and tougher due to weathering from surrounding terrain. this makes it a physical evidence that supports   the evolution of earth due to chemical weathering.

hope it !

the answer is b. glad to .