Biology Learning : Metagenesis and Metamorphosis
In growth and development, some organisms experience metagenesis and some experience metamorphosis.
Metagenesis
Do you still remember the alternation of generation in moss and ferns? Moss and ferns experience two development stages in their life span, the spore producing stage (sphorophyte generation), asexual) and the gamete producing stage (gametophyte generation, sexual)
Alternation of generations (also known as metagenesis) is the type of life cycle that occurs in those plants and algae in the Archaeplastida and the Heterokontophyta that have distinct sexual haploid and asexual diploid stages. Source
The alternation from sphorophyte to gamet or is called Pay attention to the fern metagenesis chart in Figure below :
Metamorphosis
Metamorphosis is the shape and structural alternation which occurs in animals, starting from the embryo stage to adult. Animals which undergo metamorphosis, for example, are insects and frogs.
Metamorphosis is a biological process by which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Source
Metamorphosis is differentiated into two types, namely the complete metamorphosis and the incomplete metamorphosis.
a. The complete metamorphosis
The complete metamorphosis is the metamorphosis which passes the stages egg, larva, pupa, and adult (imago). In metamorphosis, the increase of body size is a growth process, while the change of the body shape from egg to adult is development process.
Animals which undergo complete metamorphosis, for example, are butterflies and frogs. Pay attention to the Figure below.
b. The incomplete metamorphosis
The incomplete metamorphosis only passes the stages of egg, nymph (young animal), and imago (adult animal). Insects which undergo incomplete metamorphosis are, for example, grasshoppers, cockroaches, and crickets.
In the incomplete metamor- phosis, no significant change of body shape occurs. The hatched egg becomes a young animal (nymph) which shape resembles the adult insect, but the wings have not grown and the reproductory organs have not perfectly developed yet.
In its growth and development, the nymph will get bigger, it will molt its skins a couple of times (ec- dysis), and it finally becomes an adult (imago) animal and is able to reproduce. Pay attention to the metamorphosis of grasshoppers in Figure below.
