NEET BIOLOGY

Detailed explanation-1: -Gymnosperms have seed-bearing structures called cones. Female cones of pine are typically larger than male cones. The cones are surrounded by many scales. A male pine cone is usually less woody than a female pine cone. Also the male cones contain pollen, whereas female cones contain seeds.

Detailed explanation-2: -Pines, like many other conifers, produce separate male (microsporangiate) and female (macrosporangiate) cones. In many pines, male and female cones are located on different branch types; females mainly on vertical apical branches and males on lateral branches located in the middle and lower parts of the crown.

Detailed explanation-3: -male pine cones have close-knit “scales, ” that hold pollen sacks, the pollen acting as air-borne “sperm; ” female pine cones have looser scales and lie lower on a tree to make pollination easier.

Detailed explanation-4: -There are two types of cones on most Pacific NW conifers: seed cones and pollen cones. These are female and male reproductive organs, respectively. Pollen (from the pollen cones / male cones) has to reach the ovules (in the seed cones / female cones) in order to fertilize them, creating seeds.

Detailed explanation-5: -The female cones are larger than the male cones and are positioned towards the top of the tree; the small, male cones are located in the lower region of the tree. Because the pollen is shed and blown by the wind, this arrangement makes it difficult for a gymnosperm to self-pollinate.