embryonic development in frogs

Embryonic Development - All the events which change a zygote into a fully developed organism is called embryonic development. The entire process of development is called embryogenesis. Von Bear is called the "Father of Modern Embryology". ..

All the events which change a zygote into a fully developed organism is called embryonic development. The entire process of development is called embryogenesis. Von Bear is called the "Father of Modern Embryology". Embryonic Development in..

The body of the frog can be distinguished into head and trunk. The head is triangular in shape and it contains a mouth, a pair of nostrils and retractible eyes. The trunk merges with the head and lacks a neck. The trunk bears a pair of forelimbs and a pair of hind limbs. The ge..

Embryology is another branch, which offers some indirect evidences for evolution. An embryologist by name Haeckel, proposed the idea 'ontogeny recapitulates phylogeny' which means that the evolutionary history (phylogeny) of a species is indicated by the developmental stages (ontogeny) that it pas..

Parthenogenesis and Tissue Culture - Parthenogenesis is a form of reproduction in which the ovum develops into a new individual without fertilisation. Natural parthenogenesis has been observed in many lower animals (it is characteristic of the rotifers), especially insects, e.g., the aphi..

. Development involves precisely coordinated series of events. Each gene is switched on in its turn, and then something resulting from the expression of that gene, or some environmental influence, switches on the next gene in the programme. The exact mechanism of differentiation is not fu..

While the amniotic cavity is being formed, another cavity develops. This arises as an out growth from the hindgut which pushes its way into extra embryonic coelom. It is known as allanto..

The embryonic tissue layers formed during developmental stages in Eumetazoa, are called germ layers. All the adult structures develop from these germ layers. Animals in which only two primary germ layers develop (an outer ectoderm and an inner endoderm) are described a..

Cell Division - Cell division forms a mode of reproduction in unicellular organisms. In multicellular organisms it is responsible for embryonic development and growth of the adult organism. It is also involved in repair and regeneration. Both asexual and sexual reproduction requ..

Pseudocoelomata In Pseudocoelomata a false body cavity is present. It is called pseudocoelom. It is a body cavity which is not lined by mesoderm. This condition is seen in round worms (Aschelminthes). It develops from the first formed embryonic body cavity called blastocoe..