Class 12

Introduction: Spermatogenesis refers to the process through which males generate sperm from immature germ cells. It occurs in seminiferous tubules of the testes. During spermatogenesis, a diploid spermatogonium (male germ cell) develops into a diploid primary spermatocyte. This diploid primary spermatocyte undergoes its first meiotic division (meiosis I), which is a reductional division that produces […]

The spermatid is represented by a haploid male gamete that is produced by secondary spermatocyte division. Each spermatid possesses just half of the genetic material contained in the original primary spermatocyte as a result of meiosis. Cytoplasmic material connects spermatids, and there is excess cytoplasmic material around their nuclei. Early round spermatids must go through

The spermatheca is the sperm storage organs of the female reproductive tract in bees, ants, cockroaches, some molluscs, oligochaetes like earthworms, and certain other invertebrates and vertebrates like frogs. It is ectodermal in origin as outgrowths of the median oviduct generally originate near or on the genital chamber and produce a cuticle lining. It stores

Introduction Apomixis is a type of asexual reproduction in plants that involves the development of embryos and seeds rather than the fertilisation of sexual gametes.In the plant kingdom, this is a unique pathway for seed development because, in general, only gamete fusion leads to zygote formation, which leads to embryo formation, and then seed/s formation.

A population is defined as the number of organisms of the same species living in the same geographic region at the same time and capable of interbreeding. Individuals must be able to mate with any other member of a community and produce fruitful children for interbreeding to occur. Populations, on the other hand, include genetic

Introduction Like humans, seeds and fruits are also formed through fertilization. Since the world’s inception, the process of formation of a human being, seed, or fruit has remained the same. Significance of seed and fruit formation definition Reproduction is a biological process where every new individual is produced through the sperm of the father and

Rearing is the process of raising, feeding, reproducing and caring for useful animals. These animals produce one or more items that are beneficial to humans. Specimens of all sizes accepted fish and prawn food particles put to the tentacles in another investigation, however these were eventually rejected and never consumed. Factory work in warehouses, factories,

Any deviation from health is referred to as a disease. It is a damaging process that occurs in an organ or organism and has a distinct source and set of symptoms. During sexual intercourse, a variety of disease-causing microorganisms can enter the body, negatively impacting the genital and other bodily organs and organ systems. The

STD is mainly referred to as a reproductive tract infection in some circles (RTI). AIDS, Gonorrhea, Syphilis, genital herpes and warts, Chlamydiosis and Hepatitis-B are only a few of the well-known sexually transmitted diseases (STDs). Bacteria, viruses, and parasites of various strains all have a role in the transmission of sexually transmitted diseases. The majority

The term sexual reproduction includes participation of two gametes for generation of offspring. Sexual reproduction in plants involves different phases which consist of pre-fertilisation events, fertilisation and post-fertilisation events. The pre fertilisation events consist of microsporogenesis, megasporogenesis and transfer of gametes. Post-fertilization events consist of development of embryos after formation of zygote. In lower groups