The year 1900 AD is highly significant for geneticists due to
Discovery of genes
Principle of linkage
Chromosome theory of heredity
Rediscovery of Mendelism
F1-generation means
First filial generation
First seed generation
First flowering generation
First fertile generation
Which of the following cross will produce terminal flower in garden pea?
AA x Aa
AA x aa
Aa x Aa
Aa x AA
Which one of the following pairs of plants are not seed producers?
Funaria and Ficus
Fern and Funaria
Funada and Pinus
Ficus and Chlamydomonas
Study the following statements and select the correct option.
I. Tapetum nourishes the developing pollen grains.
II. Hilum represents the junction between ovule and funicle.
III. In aquatic plants such as water hyacinth and water lily, pollination is by water.
IV. The primary endosperm nucleus is triploid.
I, II, and IV are correct, but III is incorrect
I and II are correct, but III and IV are incorrect
I and IV are correct, but II and III are incorrect
I, Ill and IV are correct, but I is incorrect
Morphine, which is used as an analgesic is obtained from
Taxusbrevifolia
Berberisnilghiriensis
Cinchona officinalis
Pa paver somniferum
Darwin’s finches are an excellent example of
Adaptive Radiation
Seasonal migration
Brood parasitism
Connecting links
Vascular tissues in flowering plants develop from
Phellogen
Plerome
Periblem
Dermatogen
B.
Plerome
C.
Periblem
Histogen theory for shoot apical meristem has been proposed by Hanstein (1870). It advocates that there are three distinct meristematic zones (layers) called dermatogen periblem and plerome.
The dermatogen is the outermost histogen giving rise to the epidermis, periblem is the middle on producing the cortex and plerome is the innermost resulting in central cylinder (i.e., vascular tissue).
Cork cambium (phellogen) is the secondary lateral meristem found in the outer cortical region. Its cells divide periclinally cutting off cells towards the outside (forming cork or phellem) and inside (forming secondary cortex or Phelloderm).