Question

Which inflorescence is present in Apiaceae?
(a)Umbel
(b)Catkin
(c)Spadix
(d) Hypanthodium

Answer 1

Hint: The kind of inflorescence present in Apiaceae has, very short main axis and all flowers arise from the same point. Flowers have a centripetal arrangement, i.e older flowers towards the margin and younger flowers towards the center.

Complete answer: The inflorescence in Apiaceae is Umbel. In umbel inflorescence, the main axis is very short and bears at its tip a whorl of bracts. From the axial of each bract, arises a pedicellate flower. As in corymb, all the flowers are at the same level. In Umbel, all the pedicels are of equal length and all of them start from the apex of the peduncle. They have the centripetal arrangement which means young flowers will be arranged at the center. It actually is a racemose inflorescence. The racemose nature of inflorescence is evident from the centripetal arrangement of flowers. The peduncle is branched in an umbel manner into rays. Each ray bears reticulated flowers in an umbel manner.

Additional information:
-The main peduncle may be simple, or it may bear a cluster of flowers at the apex as in an onion.
-In compound Umbel, main peduncles may give rise to secondary peduncles, and pedicels start their tips in an umbellate manner as in coriander and carrot.
-The whorl of bracts forms an involucre. It is characteristic of the family Umbelliferae or Apiaceae.

So, the correct answer is 'Umbel'.

Note:
-Umbelliferae is a family of mostly aromatic flowering plants. It is named after the type genus Apium.
-They are commonly known as the celery, carrot, or parsley family, or simply as umbellifers. It is the 16th-largest family of flowering plants. There are more than 3,700 species.
-Racemose inflorescence is also known as indefinite or indeterminate inflorescence. In it, the main axis does not end in a flower and is capable of unlimited growth.