State the exact location of the following structures:

(i) It is present between two sister chromatids joining them.

(ii) It is present at the flaps of the bicuspid and tricuspid valves.

(iii) It is located in the neck, just below the larynx and in front of the trachea.

(iv) Extension of choroid layer as a muscular ring around the lens.

(v) It is present in the cortex region of the kidney between the Malpighian capsule and loop of Henle.