Metamorphosis in Animals - Class VIII

a) Paurometabolous metamorphosis is characterized by gradual development from the immature stage i.e nymph to the adult stage. Eg- grasshopper.

A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Caterpillar is the common name for the larvae of members of the order Lepidoptera (the insect order comprising butterflies and moths). A maggot is the larva of a fly (order Diptera). 

In each stage of complete metamorphosis, the animal looks different than at all other stages. This is different from incomplete metamorphosis where the early stages of development look like tiny versions of the adult. Butterflies are an example of an insect that goes through all the stages of complete metamorphosis.

If the sperm and egg cells of a butterfly have six chromosomes, 12 chromosomes will be there in the maggot larvae. This is because maggot larvae forms due to the fusion of egg and sperm cells. Since egg contains 6 and sperm cells contains 6 chromosomes, maggot larvae will get both sperm cell and egg cell chromosomes. Thus, the correct answer is option C.

• Parthenogenesis is a form of asexual reproduction in which organisms reproduce without fertilization. It is seen to occur naturally in bees.
•  Drone bees are produced parthenogenetically. Female worker honey bees lay only unfertilized eggs and these eggs result in drone bees. 
• So, the correct option is 'Honeybee'.

• Metamorphosis refers to the way that organisms develop, grow, and change form.
  
• Metamorphosis majorly occurs in insects.
• metamorphosis has four stages i.e egg, larva, pupa and adult.
• Caterpillars, maggots and grubs are all just the larval stages of insects.
• The hormone released during the development of a caterpillar to moth(adult insect) is called juvenile hormone(JH).
  

• Typically, insects including butterflies have 4 stages in their life cycle.
• The first stage is egg. when the eggs hatch the new insect is called a larva (second stage).
• The third stage i.e. pupa represents the transition between larva and adult ( fourth stage).

The larva is that stage in metamorphosis following which the adult stage is reached. The larvae consume a lot of food in order to fuel their transition into the adult form. Hence, during the larva stage the creature eats a lot of food which acts as the source of nutrition and energy, required for its transformation into an adult.

• Amphibian metamorphosis depends upon the amount of iodine secured by larvae; the greater the quantity the more rapid the differentiation.
  
• Also, thyroxine initiates the numerous morphological and biochemical components of amphibian metabolism.
  

• Complete metamorphosis consists of four stages i.e. egg, larva, pupa and adult.
• Incomplete metamorphosis consists of three stages i.e. egg, nymph and adult.
• Examples of organisms having incomplete metamorphosis in their life cycle are termites, praying mantis and cockroaches.

Metabolism is the sum of the physical and chemical processes in an organism by which its material substance is produced, maintained,
and destroyed, and by which energy is made available.
Metamorphosis is a profound change in form from one stage to the next in the
life history of an organism, as from the caterpillar to the pupa and from the pupa to the adult butterfly.
Metastasis the transference of disease-producing organisms to other parts of the body by way of the blood or lymphatic vessels or membranous surfaces Morphology is the branch of biology dealing with the form and structure of organisms

• Complete metamorphosis consists of four stages i.e. egg, larva, pupa and adult. 
• Incomplete metamorphosis consists of three stages i.e. egg, nymph and adult.
• Complete metamorphosis occurs in wasps, ants and butterflies while incomplete metamorphosis occurs in termites, praying mantis and cockroaches.

Moulting is the process of casting off the dead rigid outer covering or the exoskeleton or skin of the animal body during its growth. The young larvae casts off its skin in order to allow the growth of the larvae to from the adult. This process is also known as ecdysis.

Periblastula is the blastula of a centrolecithal egg, which is formed by superficial segmentation. This kind blastula occurs in insects.
Centrolecithal eggs develop to superficial blastula, which consists of a single layer of epithelial cells surrounding the centrally placed yolk and there is no blastocoele.
Thus, the correct answer is option (B).

• Metamorphosis refers to the way that organisms develop, grow, and change form.
  
• Metamorphosis majorly occurs in insects.
• metamorphosis has four stages i.e egg, larva, pupa and adult. The female lays eggs then the larva hatch from the eggs. Then the larva makes cocoons around themselves this stage is called a pupa. Inside the cocoon, the larvae change into the adult.
• Hence Changes that convert larva into adult constitute metamorphosis

Metamorphosis is the process of transformation from an immature form to an adult form in two or more distinct stages. metamorphosis generally takes place in insects or amphibians and some molluscs, crustaceans, cnidarians, echinoderms and tunicates.
Metamorphosis is seen in frogs which are developed form of the larval stage called the tadpoles. Also, metamorphosis is seen in insects where the adult forms develop from the larva and which also includes the pupal or resting stages as in silkworms.
So, the correct answer is option D.

Metamorphosis is the sequential developmental stages which are characterized by the process of cell division, differentiation, and maturation. It includes morphological and genetical changes.

Incomplete metamorphosis involves three stages: egg, nymph, and adult. The nymph resembles a small adult and undergoes gradual development through molts. Complete metamorphosis has four stages: egg, larva, pupa, and adult. Three-stage development is characteristic of insects like grasshoppers and true bugs.

Metamorphosis is the biological process where a larva transforms into an adult through drastic changes in body structure and physiology. This process is common in insects, amphibians, and other organisms. Fertilization is the fusion of gametes, cloning creates genetic copies, and metamorphosis is the correct term for this transformation.

Both amphibians and insects have larval forms. They also undergo a process called metamorphosis to come out of the larval stage. In addition to that both use DNA, RNA, ATP, the basic metabolic processes are the same. They are  multicellular organisms. they have a bilateral symmetry, they are both eukaryotes. They have  specializations of cells in regard to sensory, reproductive and metabolic systems. 

Insects shed their exoskeleton in order to grow which is known as moulting. Moulting allows the body of insects to expand under protected conditions. An instar is a developmental stage of insects, between each moult until sexual maturity is reached.

• Molting hormone or Ecdysone is produced by the prothoracic glands which regulates metamorphosis.
  
• It's principle function is to stimulate a series of physiological events (collectively known as apolysis) that lead to synthesis of a new exoskeleton.
• During this process, the new exoskeleton forms as a soft, wrinkled layer underneath the hard parts (exocuticle plus epicuticle) of the old exoskeleton.
  

Grasshoppers, cockroaches, and lice undergo incomplete metamorphosis (nymph stage), whereas mosquitoes undergo complete metamorphosis (egg, larva, pupa, adult).

Winged adults lay eggs on the food plant on which their larvae, known as caterpillars, will feed. The caterpillars grow, sometimes very rapidly, and when fully developed pupate in a chrysalis. When metamorphosis is complete, the pupal skin splits, the adult insect climbs out and, after its wings have expanded and dried, it flies off. Some butterflies, especially in the tropics, have several generations in a year, while others have a single generation, and a few in cold locations may take several years to pass through their whole life cycle.

Complete metamorphosis consists of four distinct stages: egg, larva, pupa, and adult.

• The process of growth and metamorphosis in insects is controlled by secretions of prothoracic glands and corpora allata which are ecdysone and juvenile hormone respectively.
  
• Ecdysone stimu­lates growth and shedding of the old cuticle of the larva and the new cuticle is formed beneath the old cuticle.
  
• The juvenile hormone keeps the larval cells active and also controls the qualitative changes in the body during metamorphosis.
  

Metamorphosis is a biological process by which there is a profound change in form from one stage to the next in the life history of an organism, as from the caterpillar to pupa and from the pupa to adult. Some insects, fishes, amphibians, molluscs, crustaceans, cnidarians, echinoderms and tunicates undergo metamorphosis. Humans do not undergo metamorphosis.
So, the correct answer is 'Both B and C'