Question

Unbranched, erect, cylindrical stout axis with distinct nodes and internodes and with jointed appearance called as
(a) Runner
(b) Sucker
(c) Culm
(d) Caudex

Answer 1

Hint: In these erect and unbranched stems nodes and internodes are very distinct. Adventitious roots grow from the nodes. Erect stems with distinct nodes and internodes. And stem shows a joint appearance.

Complete answer:
Clum is the erect, unbranched stems with particular hubs and internodes, nodes are swollen giving a jointed appearance. For example, bamboo.

Additional Information: - Stem is a climbing hub of the plant and creates from the plumule and epicotyl of the undeveloped organism.
-It is usually erect and grows faraway from the soil towards the sunshine. Therefore, it is negatively geotropic and positively phototropic.
-The growing apex of the stem bears a terminal bud for growth long.
Erect stems: the bulk of angiosperms possess upright, growing-ascending, vertically-erect stems. They are fixed within the soil with the assistance of roots. Erect stems belong to four categories :
(a) Culm: Erect stems with strong hubs and empty internodes. The hubs are swollen giving the stem a jointed appearance e.g., Bamboo (Bambusa arundinacea) and wheat (Triticum Vulgare).
(b) Caudex: the most stem remains unbranched and bears a crown of leaves at its top. e.g., Coconut (Cocos nucifera), Palm, etc.
(c) Excurrent: The main stem is trunk-like. It is thickest at the bottom and gradually tapers towards the apex. The branches emerge in acropetal progression, i.e., most seasoned at the base and most youthful at the zenith. The tree appears cone-shaped. e.g., Casuarina, Eucalyptus, etc.
(d) Decurrent or Deliquescent: The apical bud of the most stem is powerless when contrasted with the buds of parallel branches. Thus, the lateral branches are prominent and spreading.
So the correct answer is ‘Culm’.

Note: -The stem is differentiated into nodes and internodes in flowering plants. A node is a portion where leaves are attached to the stem. The internode is the portion of the stem between the two nodes.
- The horizontal organs of the stem (i.e., leaves and branches) are exogenous in the root (from the cortical area).
-The young stem is green and photosynthetic.
-Hair, if present, are generally multicellular.
-In mature plants, the stem and its branches bear flowers and fruits.