What is Pinus Megasporophyll?
Each megasporophyll consists of two types of scales, known as bract scales and ovuliferous scales. 6. Bract scales are thin, dry, membranous, brown- coloured structures having fringed upper part. These are also called carpellary scales.
What is the classification of Pinus?
What is apophysis in Pinus?
The cone scales of the pinus have two types of ovule. One type is called the umbo which grows in the distal region. The other part of the ovule develops from the seed scale after the fertilization in the second year which is called apophysis of the pinus ovule.
What is the gametophyte of a pine?
The Gametophyte of the Anthophyte The microsporophylls are the stamens, each tipped by the anther, which contains the diploid cells that will divide to become microspores. As in the pines, each microspore will develop into the male gametophyte, pollen.
What is male cone of Pinus?
in pinus each male cone is ovoid or oval in shape and not very large; each measures 2-4 cm in length. Only two microsporangia in pinus remain arranged side by side on the lower surface of each microsporophyll. 7. Microsporangia do not form sorus in pinus.
What is the difference between male and female pine cones?
Male cones are a lot smaller than female cones and their scales aren’t as open. Each scale in a male cone contains the pollen that can spread to a female cone to make a seed. While the shape of the cones can be pretty similar, different conifer trees within the same family can produce very different cones.
How Pinus Roxburghii is different from Pinus Wallichiana?
Pinus wallichiana (Blue pine) has needles in fasicles of 5 where as in Chilgoza pine it is 3 needles. Chir Pine (Pinus roxburghii) is a tree in lower Himalayas (elevation from 800m to 1900m). Blue pine occurs in slightly wet areas or moist areas. Hence fire occurence is less in Blue pine forests.
Is Pinus a Gymnosperm?
Pinus is a gymnosperm because it.
What are the two characteristics of pine?
Pines have acicular-shaped leaves, commonly called needles. Needles mostly occur in fascicles of 2 to 8, except Pinus monophylla, in which they usually occur singly. The fascicle sheath is comprised of bud scales which can be either deciduous or persistent. The seed cone usually matures in 2 (rarely 3) years.
What are the main characteristics of pine?
Pine wood is medium-weight and relatively soft. Its strength and elasticity are good. As with other coniferous woods, the properties of the wood depend upon the density of the annual growth rings: The higher the proportion of summerwood, the heavier and harder the wood.
What is the female gametophyte in pine?
The female and male inflorescence of the pine tree develop as cones on the sporophyte. The megaspore goes through mitotic divisions and forms a small female gametophyte, in which two or three archegonia are present, each with one egg cell. De male cone is in fact composed of numerous strobili.
Why do male and female cones look different?