In pteridophytes, phloem is without
bast fibers
Sieve tubes
Companion cells
Sieve cells
C.
Companion cells
In angiosperm, companion cells are living cells along with sieve tube and phloem parenchyma of the phloem. In pteridophytes and gymnosperm, phloem is without companion cell.
Which of the following supports a dense population of plankton and littoral vegetation?
Oligotrophic
Eutrophic
Lithotrophic
Agroecotrophic
In which one of the family formations of endosperm doesn’t take place?
Orchidaceae
Cactaceae
Ranunculaceae
Malvaceae
Source of commercial chewing gum latex is
Hevea brasiliensis
Carica papaya
Ficus elastica
Achras sapota
Read the following statements and choose the correct option.
I. Leptosporangiate development of sporangium is found in all membersPteropsida.
II. Seed habit is shown by sellaginella.
III. Gnetum leaves are monomorphic and pinnately compound.
IV. Sporic meiosis is found in Volvolx, Chalmydomonas and Ulothrix.
Choose the correct option.
I and IV
I and II
I, II and IV
All of these