Metamorphosis in Frogs and Insects Life Cycle Explained

Metamorphosis is a process in which animals like mammals, insects or even amphibians undergo rapid and extreme physical transformation sometime after birth. The process of metamorphosis can lead to changes in the entire body or simple changes in certain organs of the body. In addition to physical changes, an animal may undergo changes in their form of eating or breathing too. Common examples of metamorphism are the life cycle of a frog. In the life cycle of a frog, the animal transforms from a small tadpole to a frog. Moreover, the life cycle of a frog also experiences changes in the internal organs and systems. 

Explain the Life Cycle of a Frog

The life cycle of a frog also known as frog metamorphosis begins at the egg stage. The females lay their eggs which then hatch into tadpoles. The second step of frog metamorphosis includes the development of gills. The tadpoles develop gills that help them to breathe underwater. It is also during this stage of frog metamorphosis that the tadpoles begin to develop lungs. In the third stage, a young tadpole develops into a small frog. A small frog learns how to swim with its hind legs. The most interesting part of a frog metamorphosis is that as the amphibian grows larger, it’s tail size reduces. When the frog turns into an adult it’s tail will disappear completely, and the animal will start to eat insects instead of greens. The cycle of frog metamorphosis keeps relegating as the adult frog will once again lay eggs and produce tadpoles. 

What are the Frog Life Cycle Stages?

The frog life cycle stages begin from that of an egg and gradually develops into an adult frog. The intermediate stages include a tadpole and a young adult version of the amphibian. All the changes are accompanied by the physical and internal transformation. 

Examples

1. Life Cycle of an Insect

Answer: In an insect life cycle, metamorphism occurs in every stage. At every stage, the insect looks different from what it did earlier. In some animals, we know that the traits from the previous form may remain. But in case of an insect life cycle, that does not happen. A very common example of complete metamorphism in insects is that of a butterfly. In the very beginning comes the larva. The larva has a massive appetite and can almost eat 10 times its body weight. The larva is basically a soft worm-like structure which hardens into the pupa. The out is a hard shell inside which a fully grown butterfly will be formed. The adult butterfly sheds the hard-shelled pupa and stretches out before flying high up in the sky. A few more examples of insects undergoing metamorphism are beetles, bees, ants and moths. 

2. Name the Different Types of Metamorphism in Biology.

Answer: Based on the rate of change, metamorphism is of five types: 

• A metamorphic metamorphosis: It is the kind of metamorphism where the insects undergo very little change. 

• Gradual metamorphosis: In this kind of metamorphism that animal or insect develops changes over a gradual period of time. 

• Incomplete metamorphosis: Same as the previous type, in this kind of metamorphism the change comes gradually. 

• Complete metamorphosis: Complete metamorphosis includes a rapid change of the animal body. 

• Hyper metamorphosis: This type includes two to three different types of larva that develop into the insect. 

Fun Facts of Frog Life

1. Frogs, usually, absorb water through their skin. Hence, do not have drinkable water. 

2. In the complete life cycle of a frog, an adult frog can lay as many as 4,000 eggs. 

3. Frogs are popularly known for jumping. Some of the frogs can jump as high as 20 times their own body weight in a single leap. 

4. It is a common misconception that frogs are inky green in colour. There are a few frogs which are brightly coloured but very poisonous in nature. 

5. At birth frogs have a long tail, but as they grow into adults the tail disappears. 

Significance of Metamorphosis

One of the important components that contribute to the survival of insects is metamorphosis and hence it can be called a successful strategy. Many insects have juvenile phases with environments that are very distinct from the grownups. As a result, bugs can often make use of abundant food resources despite still being able to spread into other environments as adults. Metamorphosis dramatically increases the possibility for adaptability and development.

A Brief About Growth and Maturity

There is one thing to keep in mind when it comes to metamorphosis. Insects cannot mate or reproduce till they have completed their last moult or have emerged as a winged mature insect from a pupa. Wings aren't visible till the last moult, there are a few exceptions of course. When you observe an insect with wings, it means it has reached adulthood. This means that little flies do not grow larger; they just reach their maximum size.

Hormonal Control in Metamorphosis

Iodothyronine-induced metamorphosis is an ancestral trait of all chordates. Hormones produced by endocrine glands towards the front of the body control insect growth and metamorphosis. The prothoracicotropic hormone (PTTH) secreted by neurosecretory units in an insect's brain stimulates prothoracic glands, which emit another hormone, which is usually ecdysone, which causes ecdysis. The corpora allata, a retrocerebral organ, is also stimulated by PTTH, which produces the juvenile hormone, which blocks the growth of adult features after ecdysis. 

Moults between larval instars have a significant amount of juvenile hormone, moults to the pupal phase have a lower degree of juvenile hormone, and the ultimate, or interoceptive, moult has no juvenile hormone at all in holometabolous insects. The amount of nymph instar stages in hemimetabolous insects can be influenced by juvenile hormone, according to experiments on firebugs.

Importance of Note-Making in Biology 

Note-making is an important aspect of your preparation for the exams. Note-making helps build concentration and keep you proactive and interested during your study session. comprehending what you're learning and clarifying your thoughts selectively choose key concepts. It also saves time and helps you revise better especially in your end-time preparations.