Flowers can either be complete or incomplete. Complete flower consists of:

• Petals: This is the brightly colored part which attracts bees, insects, and birds. Colour of petals varies from plant to plant; some are bright while some are pale colored. Thus, petals help us to differentiate one flower from another.

• Sepals: Sepal is the green colored part beneath the petals to protect rising buds. Some flowers have fused petals-sepals but some have separated petals-sepals.

• Stamen: This is the male reproductive organ and consists of two parts namely: anther and filament which are usually yellow. Anther is a sac that produces and stores pollen whereas filament supports the anther.

• Pistil: This is the innermost part of the flowers. The female reproductive organ of a flower comprises of three parts – stigma, style, and ovary which are collectively known as pistil. Stigma is the top most part; style is the long tube which connects stigma to the ovary. The ovary has lots of ovules. It is the part of the plant where the seed formation takes place.

In different plants, the number of petals, sepals, stamens and pistils can vary. Also, all these parts might not present in all plants. Based on this, we can decide whether a flower is complete or incomplete. Depending on the  parts present, flowers are either a male or a female or both.

The process of formation of megaspores from the megaspore mother cell is called megasporogenesis. Ovules generally differentiate a single megaspore mother cell (MMC) in the micropylar region of the nucellus. MMC a large cell containing dense cytoplasm and a prominent nucleus. The MMC undergoes meiotic division which results in formation of four megaspores.

Terrestrial animals are either ureotelic or uricotelic, and not ammonotelic. This is because of the following two main reasons:

(a) Ammonia is highly toxic in nature. Therefore, it needs to be converted into a less toxic form such as urea or uric acid.

(b) Terrestrial animals need to conserve water. Since ammonia is soluble in water, it cannot be eliminated continuously. Hence, it is converted into urea or uric acid. These forms are less toxic and also insoluble in water. This helps terrestrial animals conserve water.

In simple words, osmoregulation is the control of the water and electrolyte balance in the body.

Osmoregulation ensures the active regulation of the osmotic pressure of bodily fluids to maintain the homeostasis of the body's water content; that is it keeps the body's fluids from becoming too dilute or too concentrated. Organisms in all environments (aquatic and terrestrial) must maintain the right concentration of solutes and amount of water in their body fluids.

Embryogenesis: The process of development of the embryo from the zygote is called embryogenesis. Development of the offspring from reproductive units such as buds or fragments in asexual reproduction is called blastogenesis. Both embryogenesis and blastogenesis have the same target - to develop a new individual by the process of cell division and differentiation.

Apomixis is the method involved in production of seeds without fertilisation.Apomixis has an advantage of producing inividuals with desired qualities in more numbers.
Apomixis is a type of asexual reproduction which is genetically controlled. There is a development of embryos and seeds without meiosis taking place in the female to produce eggs and thereby prevnting its participation in fertilisation. Apomixis helps in the enormous amount of seed production which are exact replicas of the mother plant. 

The vascular cambium and cork cambium are secondary meristems that are formed in stems and roots after the tissues of the primary plant body have differentiated. The vascular cambium is responsible for increasing the diameter of stems and roots and for forming woody tissue. The cork cambium produces some of the bark. Cork cambium is a tissue found in many vascular plants as part of the periderm. The cork cambium is a lateral meristem. It is responsible for secondary growth that replaces the epidermis in roots and stems. ... The function of cork cambium is to produce the cork, a tough protective material and secondary cortex.

The tapetum is the innermost layer of the microsporangium. It provides nutrition to the developing pollen grains. It secretes enzymes, hormones and special proteins for the pollen grains to recognise compatibility. It also produces the exine layer of the pollen grains, which is composed of the sporopollenin. The tryphine that coats the pollen grains of Raphanus is tapetal synthesized and is composed of a fibro-granular and a lipidic component. The fibro-granular material is proteinaceous and is secreted by cisternae of the endoplasmic reticulum. The lipidic component is derived, mainly, from degraded elaioplasts. The fibro-granular material is applied to the pollen exine first, followed by the lipidic mass. The tryphine condenses during the final stages of pollen maturation and dries down to form a thick, highly viscous coating. The major part of the condensation appears to result from dehydration. The tryphine, extracted from the pollen by a centrifugal method and mounted in a membrane, appears to be capable of penetrating the outer layers of a stigma of the same species and, if the pollen from which it was derived is incompatible with respect to the stigma, the stimulation of the production of the callosic reaction body in a manner similar to an incompatible pollen tube. It is proposed that, in Raphanus, substances responsible for the initiation of at least two stages in the self-incompatibility system are held in the tryphine.

In biology, cloning is the process of producing similar populations of genetically identical individuals that occurs in nature when organisms such as bacteria, insects, plants or animals reproduce asexually. Cloning in biotechnology refers to processes used to create copies of DNA fragments (molecular cloning), cells (cell cloning), or organisms(organism cloning). The term also refers to the production of multiple copies of a product such as digital media or software.

The term clone, invented by J. B. S. Haldane, is derived from the Ancient Greek word κλώνklōn, "twig", referring to the process whereby a new plant can be created from a twig. In horticulture, the spelling clone was used until the twentieth century; the final e came into use to indicate the vowel is a "long o" instead of a "short o".  Since the term entered the popular lexicon in a more general context, the spelling clone has been used exclusively.

Operon: An operon is a gene which codes for several proteins and is regulated by common promoter and regulatory genes. An example of an operon is Lac operon which is present in organisms like E.coli. Each operon has specific operator and a specific repressor.