Chapter 6

Select the incorrect statement among the following: (a) Ring arrangement of vascular bundle is a characteristic of dicot stem. (b) Phloem parenchyma is absent in monocot stem. (c) Monocots have sclerenchymatous hypodermis. (d) In monocot, peripheral, vascular bundle, which are generally large and centrally located are small and water containing cavities are present within the vascular bundle.

Which of the following is correct about dorsiventral leaf? (a) The veins vary in thickness in the reticulate venation. (b) Palisade parenchyma is abaxially placed. (c) Abaxial surface bears no stomata. (d) The size of vascular bundles are independent on the size of veins.

Which of the following is incorrect about isobilateral leaf? (a) Stomata is present on both surfaces (b) Undifferentiated mesophyll (c) Nearly the same size of vascular bundle is present all over leaf (d) It is a monocot leaf

The growth of the roots and stems in length with the help of apical meristem is called (a) Secondary growth (b) Primary growth (c) Both (a) and (b) (d) None of these

Dicot plant exhibits an increase in girth. It is an example of (a) Secondary growth (b) Primary growth (c) Both (a) and (b) (d) None of these

Cells of cambium present between primary xylem and primary phloem forms (a) Interfascicular cambium (b) Intrafascicular cambium (fascicular cambium) (c) Cork cambium (d) None of these

Vascular cambium is formed by I. Interfascicular cambium II. Intrafascicular cambium. III. Cork cambium (a) I and III only (b) II and III only (c) I, II and III only (d) I and II only

Cambium wing forms cells towards (a) Inner side of ring (b) Outer side of ring (c) Both side of ring (d) They do not form cells

The vascular cambium activity is (a) More on inner side than outer (b) More on outer side than inner (c) Equal on outer and inner side (d) None of these

The following will not happen during secondary growth by cambium ring: (a) Secondary xylem produced is more than secondary phloem. (b) Primary and secondary phloem is crushed due to continued formation and accumulation of secondary xylem. (c) Primary xylem remains more or less intact in or around centre. (d) The cells cut off towards pith mature into secondary phloem and cells cut off towards periphery mature into secondary xylem.

During secondary growth all occur except (a) Secondary medullar rays forms (b) Phloem crushed (c) Primary phloem forms (d) Secondary xylem forms

The activity of cambium is under control of (a) Physiological factor (b) Environmental factor (c) Both (a) and (b) (d) None

Select the total number of correct statements from the following: (1) In spring season cambium is active and produces a large number of xylary elements having vessels with wider lumen. (2) The spring wood is also known as early wood. (3) In winter, the cambium is less active and forms few xylary elements having narrow vessels this is called autumn wood or late wood.(4) The spring wood is lighter in colour and has lower density. (5) Autumn wood is darker and has higher density. (6) Annual ring (autumn wood and spring wood) used to estimate the age of plant. (a) 3 (b) 4 (c) 5 (d) 6

In older trees, the greater part of secondary xylem is dark brown due to the deposition of (a) Tannins and resins (b) Oil and gums (c) Aromatic substance and essential oil (d) All of these

The dark brown deposition of organic compound in heartwood will make it (a) Hard (b) Durable (c) Resistant to microbes and pest (d) All of these

Heartwood contains (a) Live lignified element (b) Dead highly lignified element (c) Live non-lignified element (d) Dead non-lignified elements

The function of heartwood is (a) Conduction of water (b) Conduction of mineral (c) Conduction of food (d) Mechanical support

Peripheral region of secondary xylem, which is light in color is known as (a) Heartwood (duramen) (b) Sapwood (alburnum) (c) Spring wood (d) Autumn wood

The cells of secondary cortex are (a) Parenchymatous (b) Sclerenchymatous (c) Collenchymatous (d) Meristems

Bark refers to (a) Periderm (b) Secondary phloem (c) Both (a) and (b) (d) None of these

At certain region, the phellogen cuts off closely arranged parenchymatous cells on the outer side instead of cork cells. These parenchymatous cells soon rupture epidermis, forming a lensshaped opening called (a) Hydathodes (b) Stomata (c) Lenticels (d) None of these

Which of the following is correct about lenticels? (a) It is present in most of the woody trees (b) It helps in gaseous exchange (c) It is formed by the activity of phellogen (d) All of these

In dicot root, the vascular cambium is (a) Completely primary in origin (b) Partly primary and partly secondary (c) Completely secondary in origin (d) None of these

Initially formed cambium in dicot root is (a) Circular (b) Rectangular (c) Oval (d) Wavy

Secondary growth occur in (a) Dicot root (b) Dicot stem (c) Stem and root of gymnosperm (d) All of these

Which of the following is incorrect? (a) Wood is actually a secondary xylem. (b) Different type of woods are found on basis of their composition and time of production. (c) Monocot and dicot show marked variation in their internal structure. (d) Increase in girth of dicot stem by vascular cambium only.

Main functions of plant tissues are (a) Assimilation of food and its storage (b) Transportation of water, mineral and photosynthates (c) Mechanical support (d) All of these

Cambium causes growth in (a) Circumference (b) Width (diameter) (c) Leaves (d) Length

The function of cork cambium (phellogen) is to produce (a) Cork and secondary cortex (b) Secondary xylem and secondary phloem (c) Cork (d) Secondary cortex and phloem

In dicot roots, the vascular cambium is derived from (a) Epidermis (b) Hypodermis (c) Cortex (d) Pericycle

Periderm is made up of (a) Phellem (b) Phellogen (c) Phelloderm (d) All of these

Cork cells are (a) Dead (b) Photosynthetic (c) Elongated and participates in movement (d) Meristematic

Annual rings are distinct in plants growing in (a) Tropical regions (b) Arctic region (c) Grasslands (d) Temperate region

Xylem, which is functional in a dicot tree is (a) Spring wood (b) Sap wood (c) Autumn wood (d) Heart wood

External protective tissues of plants (of dicot stem are) (a) Cork and pericycle (b) Cortex and epidermis (c) Pericycle and cortex (d) Epidermis and cork

Cork cambium is a (a) Secondary meristem (b) Apical meristem (c) Intercalary meristem (d) Primary meristem

Cambium, which produces cork is known as (a) Phelloderm (b) Phellogen (c) Periblem (d) Periderm

Dendrochronology is the study of (a) Height of a tree (b) Diameter of a tree (c) Age of a tree by counting the number of annual rings in the main stem (d) None of these

The tissue made up of thin-walled rectangular cells responsible for the secondary growth is (a) Cortex (b) Xylem (c) Cambium (d) Pith

In old dicot stems, a major part of the wood is filled up with tannins, resins, gums, etc. This part of wood is called (a) Hard wood (b) Heart wood (c) Sap wood (d) Soft wood

Lenticel develops through the activity of (a) Vascular cambium (b) Dermatogens (c) Phellogen (d) Intercalary meristem

The waxy substance associated with cell walls of cork cells are impervious to water because of the presence of which gets deposited on cork cells (a) Cutin (b) Suberin (c) Lignin (d) Hemicellulose

Growth rings determines the (a) Age (b) Length (c) Breadth (d) Number of branches of a plant

Lenticels are formed in bark, which are (a) Aerating pores (b) Made up of phloem (c) Made up of xylem (d) Found in monocot plants

Heart wood or duramen is the (a) Outer region of secondary xylem (b) Inner region of secondary xylem (c) Outer region of secondary phloem (d) Inner region of secondary phloem

The bark of tree comprises of (a) All the tissues outside the vascular cambium (b) All the tissues outside the cork cambium (c) Only the cork (d) The cork and secondary cortex

Bulliform or motor cells are present in (a) Dicot stem (b) Upper epidermis of dicot leaves (c) Lower epidermis of monocot leaves (d) Upper epidermis of monocot leaves

Exarch and polyarch vascular bundles occur in (a) Monocot stem (b) Monocot root (c) Dicot stem (d) Dicot root

In root, the xylem is (a) Mesarch (b) Exarch (c) Placed at different places in different plants (d) Endarch

In monocot leaf (a) Bulliform cells are absent from the epidermis (b) Veins form a network (c) Mesophyll is well differentiated into these parts (d) Mesophyll is not differentiated into palisade and spongy parenchyma