During which phase of meiosis do tetrads line up in the middle of the cell?

Meta phase I stage of meiosis

Explanation:

The tetrads (group of two chromosomes) are formed during the prophase I stage of cell division where they lie close to each other.  

While during the metaphase – I stage  of cell division, these tetrads align themselves along the metaphase plate which lies at the center of the cell and in future divides the cell into two equal halves.

is called echinoderms

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 !