Both apical meristems and intercalary meristems:-
I. Are primary meristems
II. Appear early in plant life
III. Contribute to the formation of the primary plant body
1. Only I and II are correct
2. Only I and III are correct
3. Only II and III are correct
4. I, II and III are correct
All statements are true.The cells of intercalary meristems possess the ability to divide and produce new cells.They are situated between regions of mature tissue, such as at the base of grass leaves, which are themselves located on mature stem tissue. Intercalary meristems are largely responsible for elongation in grass shoots and leaves. In rosette plants, intercalary meristems are lacking.
The most impotant function of the trichomes is:
(1) They prevent water loss due to transpiration
(2) They prevent herbivory
(3) They are sensory structures that decipher the wind velocity and direction
(4) They play an important part in pollination of plants
(1) Trichomes are epidermal hairs on the sterm and help in prevention of water loss due to transpiration.
Identify the incorrectly matched pair:-
1. cork cambium - periderm
2. ground meristem - cortex and pith of a dicot stem
3. procambium - primary vascular tissue
4. protoderm - vascular tissue of a monocot stem
Protoderm is the primary meristem in vascular plants that gives rise to epidermis. It is also called dermatogen.
Which of the following has unevenly thick cell wall, has a primary wall (cellulose) and a secondary wall (hemicellulose or pectin), and is a simple, living, primarily mechanical tissue of the plant body?
Answer 2. Collenchyma cells are much thickened at the corners due to a deposition of cellulose, hemicelluloses and pectin.
Intercalary meristems are primary meristems because:
I. They appear early in life of a plant.
II. They contribute to the formation of the primary plant body.
(1) Only I is correct
(2) Only II is correct
(3) Both I and II are cerrect
(4) Both I and II are incorrect.
(3) Read page 85 XI NCERT
Identify the correct statement regarding collenchymas in plants:-
1. They occur in layers below the epidermis of monocotyledonous plants.
2. Cells are much thickened at the corners due to the deposition of lignin.
3. Collenchymatous cells do not contain chloroplasts.
4. They provide mechanical strength to the growing parts of the plant.
Read page 86 of XI NCERT
What is the number of correct statements amongst the following regarding phloem tissue of plants?
I. Gymnosperms lack albimunous cells and
II. The companion cells are specialized
III. Phloem parenchyma is absent in most of the
IV. Phloem fibers are generally absent in the
Statement I is incorrect. Read page 88 of class XI NCERT
In dicot roots, the initiation of the lateral roots and the vascular cambium during the secondary growth takes place in:
(3) Conjuctive tissue
(1) Read page 91 XI NCERT
In dicot stem the vascular bundle is:-
1. Conjoint, open and with exarch protoxylem.
2. Conjoint, open and with endarch protoxylem.
3. Conjoint and closed.
4. Scattered, each surrounded by a sclerenchymatous bundle sheath.
Read page 93 of XI NCERT
1. Are found in dorsiventral leaves and help in photosynthesis.
2. Are found in dorsiventral leaves and help in minimizing water loss.
3. Are found in isobilatetral leaves and help in minimizing water loss.
4. Are found in isobilatetral leaves and help in photosynthesis.
Read page 94, XI NCERT