MCQ
Which of the following is essential for thyroid gland?
- A$\text{NaCl}$
- ✓$I_3$
- C$\ce{CaCO_2}$
- D$\ce{H_2CO_3}$
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| Column $I$ | Column $II$ | ||
| $A.$ | Porifera | $i.$ | Canal system |
| $B.$ | Aschelminthes | $ii.$ | Water$-$vascular system |
| $C.$ | Annelida | $iii.$ | Muscular pharynx |
| $D.$ | Arthropoda | $iv.$ | Jointed appendages |
| $E.$ | Echinodermata | $v.$ | Metameres |