Anatomy of Flowering Plants Test - 47

In dicot stem, during secondary growth, when new secondary xylem formation is going on, oldest secondary xylem appear outside the primary xylem.

In mature monocot roots, after the loss of epidermis, the outer cells of general cortex are suberised become thick-walled layer called exodermis.

So, the correct option is ‘Monocot root’.

The corky outer layer of a plant is commonly called the periderm. It has three parts- the cork cambium (phellogen), the cork (phellem), and the secondary cortex (phelloderm). It usually forms as a result of secondary thickening in the case of an injury.

In the endodermal cells, lingo-suberised thickenings are present on the radial and tangential cell walls. These are called Casparian strip.

So the correct option is ‘Ligno-suberised band running in endodermal cell walls.

A ring of secondary xylem or wood formed by the association of spring or early wood and autumn or late wood is called annual ring or growth ring.

So, the correct option is ‘Growth ring’.

A.Pea – three xylem strands are present.

B.Sunflower – four xylem strands are present.

C.Ficus – more than six xylem strands are present.

D.Ranunuculus – four xylem strands are present.

So, the correct option is ‘Ficus’.

A. Collateral and closed – in the vascular bundles, xylem and phloem on the same radius, but cambium is absent. These are present in leaves and monocot stem.

B.Collateral and open – In the vascular bundles, xylem and phloem are present on the same radius, cambium is present. These are found in dicot stem.

C.Conjoint and concentric – Not found in any plants

D.Radial – In the vascular bundles, xylem and phloem are present on different radii. These are present in roots.

So, the correct option is ‘collateral and closed’

A.Dicot root – phloem parenchyma is present.

B.Dicot leaf – Phloem parenchyma is present.

C.Monocot stem – phloem parenchyma is absent.

D.Dicot stem – Phloem parenchyma is present.

So, the correct answer is 'Monocot stem'.

A. Cork cambium – a ring of meristematic tissue or cambium formed by the dedifferentiation of parenchyma present in the general cortex.

B. Vascular cambium – a ring meristematic tissue or cambium, formed by the association of intra and interfascicular cambium.

C. Intercalary meristem – it is a type of meristem present between the permanent tissues of stem apex of grasses.

So, the correct option is – ‘Both A and B’.

In the dicotyledonous trees growing in temperate regions, because of the existence of maximum seasonal variations, during secondary growth, vascular cambium is more active during the spring season and produces spring wood and whereas in the autumn season, it is less active and produces autumn wood or latewoods. These two kinds of wood together form into annual rings or growth rings.

So, the correct option is ‘Cambium’.