Botany and Plant Science

Heterospory, seed formation and fertilization are found in gymnosperm. 

• Guard cells are cells surrounding each stoma. They help to regulate the rate of transpiration by opening and closing the stomata. 
• Lenticels are one of many raised pores in the stem of a woody plant that allows gas exchange between the atmosphere and the internal tissues. Bulliform cells are large, bubble-shaped epidermal cells that occur in groups on the upper surface of the leaves of many grasses. Loss of turgor pressure in these cells causes leaves to "roll-up" during water stress. 
• Subsidiary cell is a plant epidermal cell that is located next to a guard cell in the stoma of a leaf and differs in structure from other epidermal cells. Also called an accessory cell.

Promeristem are groups of meristematic cells found in germinating embryos or young seedlings. They give rise to primary meristems which initiate the organ formation process. Promeristems are also referred as primordial meristems or embryonic meristems because of their origin.
Thus, the correct answer is option A.

• In plants, receptacle or thalamus is a thick part of the stem from which the flower organs grow. Stipule is a small leafy outgrowth at the base of the leaf. The sepals of a flower that form a whorl enclosing the petals and forms a protective layer around the flowers.
• Carpels, on the other hand, is the female reproductive organ in a flower consisting an ovary, a stigma and probably a style. It produces egg cells and protects a developing baby plant.

Some plants are characterized by well-developed pulvini, small swelling at the base of the leaves, on the shoots. These leaves are individually attached, flattened and helically arranged. Pulvinus facilitates growth independent movement and is common in members of Fabaceae family.

The tendril of sweet pea is a modification of the terminal leaflet of the leaf into a slender wiry and coiled structure that helps in support of the plant.

• Suberin is a cell wall constituent that forms gas and watertight layers. It is part of the Casparian strip of the root endodermis, where it acts as a diffusion barrier between the apoplast of the root cortex and the central cylinder.
• Suberin is present in many C4 plants as an impermeable layer between the bundle sheath and mesophyll cells.
  

Areoles are the evolutionary modification in the cacti. These modifications give rise to spines and glochids which are the means of self-defense. These spines effectively cover the cacti. These evolved as abortive branch buds while their spines evolved as vestigial leaves.

In Duranta, axillary buds and in Carrisa the apical bud is modified into stem thorns, for ulex both stem thorns as well as leaf spines are modified.
Hence, option D is correct.

Sori are asexually reproducing structures produced on the abaxial surface of the leaf and produce haploid spores, that germinates to form the independent gametophyte.

Mosses have two forms of reproduction. Asexual or vegetative reproduction and sexual reproduction. Mosses produce small sexual structures known as archegonium (the female structure that produces egg cells), or antheridium (the male structure that produces sperm cells). In moss, the zygote formation begins the second phase of the moss life cycle where the zygote develops into the sporophyte (spore-plant). The sporophyte consists of three structures, a foot which anchors it to the gametophyte and helps to transfer water and nutrients from the gametophyte, a long erect stalk called a seta and a pod-like capsule at the end where spores are produced. So the correct option is "Moss".

When the conditions are favorable the zoospores were formed. The cell becomes no motile during the formation of zoospores and the flagella are distracted or retracted.