What is an imaginal disc? An imaginal disc is a sac-like epithelial structure found inside the larva of insects that undergo metamorphosis. Once the larva turns into a pupa, almost all the larval tissues degenerate and the imaginal discs turn into the external structures of the head, thorax, limbs and genitalia.
What is the function of imaginal discs?
Discs serve as a canvas to experimentally address how cells and tissues respond to gain or loss of specific gene functions. The potential of using imaginal discs to aid future discoveries remains unchallenged, thus promising further contributions in cell and developmental biology.
Why are discs called imaginal?
Why are they called imaginal discs? That’s easy… ‘imago’ is a Latin word that means ‘image’ and is used by entomologists to refer to the mature stage of insects. The imaginal discs get their name since they are ‘disc’-shaped structures that will originate the imago.
Are imaginal discs necessary features of insect metamorphosis?
Imaginal disks are epithelial structures characteristic of insects that undergo complete metamorphosis. … The genes controlling the development of the imaginal disks are conserved in vertebrates. Similarly, the cellular processes underlying the development of imaginal disks are also conserved through evolution.
What are imaginal cells?
Imaginal cells are tissue-specific progenitors allocated in embryogenesis that remain quiescent during embryonic and larval life. During Drosophila metamorphosis, most larval cells die. Pupal and adult tissues form from imaginal cells.
Are imaginal cells stem cells?
Transdetermination: Drosophila imaginal disc cells exhibit stem cell-like potency. Int J Biochem Cell Biol. 2007;39(6):1105-18.
What does the word imaginal mean?
Definition of imaginal
(Entry 1 of 2) : of or relating to imagination, images, or imagery. imaginal. adjective (2)
What structures do the imaginal discs form and at what point in the life cycle do they differentiate into these structures?
Imaginal Disks
These epithelia originate during embryonic development from groups of ectodermal cells that grow during the larval stages to form the mature disk. The imaginal disks differentiate into most of the structures of the adult insect, such as the legs, wings, and head.
Which embryonic stage of Drosophila is used for dissection of imaginal disc?
The protocol can be used to dissect imaginal discs from younger first and second instar larvae as well. The advantage of this protocol is that it is relatively short and it has been optimized for the high quality preservation of the dissected tissue.
Do Hemimetabolous insects have imaginal discs?
And although the term imaginal disc is used only for holometabolous insects, it is only the invaginated morphology of most discs that distinguishes them from structures like the external wing pads of hemimetabolous insects, which also are morphologically distinct and form adult wings during the final molt.
Are grasshoppers Holometabolous?
In more advanced insects (e.g., grasshoppers, termites, true bugs) a phenomenon known as gradual, or hemimetabolous, metamorphosis occurs. The hemimetabolous life cycle consists of egg, nymph, and adult.
Can a caterpillar turn into a butterfly?
The caterpillar, or what is more scientifically termed a larva, stuffs itself with leaves, growing plumper and longer through a series of molts in which it sheds its skin. … Within its protective casing, the caterpillar radically transforms its body, eventually emerging as a butterfly or moth.
What is the life cycle of Drosophila?
The Drosophila life cycle is divided into four stages: embryo, larva, pupa, and adult. The time length of the stages is approximate and is shown in hours for embryos and days for larvae and pupae.
What are butterfly cells?
The wings of butterflies are formed from a group of cells that are set aside during the embryonic stage, in the form of imaginal discs. These imaginal discs grow inside the larval body as the larvae grow, but in the pupal stage the imaginal discs move to the outside of the body and develop their final size and shape.
What is butterfly metamorphosis?
The butterfly and moth develop through a process called metamorphosis. This is a Greek word that means transformation or change in shape. … There are four stages in the metamorphosis of butterflies and moths: egg, larva, pupa, and adult.
Who coined the term imaginal?
The phenomenological term &dquo;imaginal&dquo; was coined and intro- duced. into the French language by Henry Corbin (1903-1978).
What is the imaginal realm?
The imaginal realm is a meeting ground, a place of active exchange between two bandwidths of reality. That is how its cosmic purpose is fulfilled and—I will attempt to demonstrate shortly—the way in which it can be most fruitfully understood.
How many species of fruit flies are there?
There are more than 4000 fruit fly species all over the world. But so far, there are four major species of fruit flies that are considered super pests – the Mediterranean fruit fly, Mexican fruit fly, Caribbean fruit fly, and Queensland fruit fly.
Why does metamorphosis exist?
The primary advantage of complete metamorphosis is eliminating competition between the young and old. Larval insects and adult insects occupy very different ecological niches.
What are the 4 stages of metamorphosis?
Complete metamorphosis has four distinct stages: egg, larva, pupa, and adult. Beetles, such as ladybugs, are one kind of insect that grows through complete metamorphosis!
Are Orthoptera Hemimetabolous?
Hemimetabolous (incomplete metamorphosis)
Typical hemimetabolous insects are the Hemiptera (Scales, Aphids, Whitefly, Cicadas, Leafhoppers and True Bugs), Orthoptera (Grasshoppers and Crickets), Mantodea (Praying Mantids), Blattodea (Cockroaches), Dermaptera (Earwigs) and Odonata (Dragonflies and Damselflies).
What is the difference between holometabolous and hemimetabolous?
Holometaboly refers to the complete metamorphosis. … The key difference between Holometabolous and the Hemimetabolous insects is based on the type of metamorphosis they undergo. Holometabolous insects undergo complete metamorphosis whereas Hemimetabolous insects undergo incomplete or partial metamorphosis.
Are lice holometabolous or hemimetabolous?
The sucking and chewing lice (Phthiraptera) are hemimetabolous insects that spend their entire lives on the bodies of their hosts. Fleas (Siphonaptera), on the other hand, are holometabolous. The diversity of these ectoparasites is limited by the diversity of the birds and mammals available as hosts.
Are mites holometabolous?
The adult female mites are mostly parasitic on insects. Their host range includes many holometabolous insects such as honeybees, bark-boring beetles, moths and stored product pests. They parasitise various development stages of their host species but mostly it is the larvae which are attacked.
Do caterpillars feel pain?
They don’t feel ‘pain,’ but may feel irritation and probably can sense if they are damaged. Even so, they certainly cannot suffer because they don’t have emotions.
Do caterpillars have brains?
First, caterpillars do not have brains. Invertebrates are some of the most primitive creatures on earth. They have nervous centers, but that’s about it.
What’s inside a chrysalis?
Before becoming butterflies, caterpillars enter the pupa stage, where they build that little sack, or chrysalis. The chrysalis protects the caterpillar as it begins to turn itself into a liquid, soupy substance. … The new butterfly’s organs, wings, antennae, and legs form inside the chrysalis.
Why is Drosophila called fruit fly?
Drosophila derived from the Greek word drósos means dew loving. They belong to the Droso–philidae family; and are most frequently known as fruit flies or often called vinegar, wine or pomace flies. Their main distinguishing character is to stay on fruits, which are ripped or rotten.
Why Drosophila is studied?
Drosophila has been used productively as a model organism for over a century to study a diverse range of biological processes including genetics and inheritance, embryonic development, learning, behavior, and aging.
Where are Drosophila found?
Drosophila species are found all around the world, with more species in the tropical regions. Drosophila made their way to the Hawaiian Islands and radiated into over 800 species. They can be found in deserts, tropical rainforest, cities, swamps, and alpine zones.