Physiology Development of Insects

1. Entomology TTh 3:00-4:30
-BY
Barz ,christine jane .N
Bokingkito , maybelle
Bomma reddy sai sri krishna reddy
Bureddi Anudeep venkata sai
Chinthala ranadheer reddy
Chinthalapudi nithya

2. Physiology Development
Metamorphosis
Hormonal regulation of Development
-Ecdysone
-Juvenile Hormone
-Brain Hormone
Suspended Activity:
Diapause

3. DEVELOPMENT
-The growth from egg to the functional reproducing
stage Is called development.

4. Physiology Development
-Epidermis and tracheal system are
reconstructed
-Nervous system enlarges rapidly by the growth
of the constituents parts
-Heart grows without marked change
-Digestive tract is changed by the growth or
reduction of some parts and the remodeling of
others

5. METAMORPHOSIS
-biological process
-an animal physically develops after the birth or hatching or
involving conspicuous and relatively abrupt change in
animal body structure through cell growth and differentiation.
-in insects complete metamorphosis occurs at PUPAL STAGE.
-this has special function in nervous, reproductive and
digestive systems.
-these adult parts have build up two phases:-

6. HISTOLYSIS
-Breaking down process especially in tissues
essentially in catabolism , leukocytes and enzymes
convert the larval fat body, much of the muscle
tissue, undoubtedly parts of other tissue also, and the
later the leukocytes themselves, into a nutritive
matrix transportable by the blood to growing tissues.
HISTOGENESIS
Representing anabolism
-Construction of adult tissues from products of
histolysis
-These process occur simultaneously,before pupation
the larve under goes this stage.
-The store of fat and glycogen accumulated by the
larva during its feeding period are drawn upon for a
food source.

7. Quiescent stage- conversion process
begins. They continue through the
pupal stage until the adult structure is
complete. During these processes, the
stores of fat and glycogen
accumulated by the larva during its
feeding period are drawn upon for
food source.

8. HORMONAL REGULATION AND DEVELOPMENT
Ecdysone
-Small gland variously shaped in different insects in prothorax
-prothoracic gland secrete this hormone for molting.
-produces growth and development.
Juvenile hormone
-copra allata secrete this hormone retards the development
of adult structures responsible for the maintenance of
nymphal or larval characters during pre-adult life.
-necessary of the development of ovaries.

9. Brain hormone
Activates prothoracic gland to produce ecdysone and
corpora allata later direct to nerve connection .
-response leads to cause molting and development in adult
structures.
-the rabbit flea spilopsyllus cuniculi require a hormone this
has effect Synchronizing the reproductive cycles of both
the flea and rabbit host.
-the brain hormone and ecdysone are steroids this explain
the insects dietary need for cholestrol (a possible steroid
processor).
-the juvenile hormone apper as to be complex alcohol or
its derivative .

10. Suspended activity : Diapause
A period during which growth or development is suspended
and physiologicalactivity is diminished,as in certain insects
in response to adverse environmental conditions.
spontaneous interruption of the development of certain
animals, marked by reduction of metabolic activity.
Ex:- platysarmia cerropia
-linked with in seasonal changes in day light ,or
photoperiodism.
-this may has different relationship with different species.
In polychrosis pupal diapause determined in photoperiodic
conditions of embryonic development.

11. -In the moth Polychrosis pupal diapause is
predetermined by the photoperiodic conditions of
embryonic development.
-In the beetle leptinotersa, on other hand long
photoperiod experienced by the late larva may cause
them to enter the diapause as soon as they enter into
the ground.
-In the silkworm bombyx a lengthening photoperiod
triggers diapause .

12. -The principal of termination of diapause seems to be
exposure to the temperature below those favoring
development.
-Unchilled grasshopper plays a role in this how ever the
other insects may complete apply of water during
diapause.
-The length of the diapause varies to tremendous extent ,
ranging from little more Than one week to twelve years .
-certain species have several generation of years ,all the
generations do not act like With respect to diapause.
-The differential behavior is linked with genetic factors, but
there is interplay with the factors of the environment has
to be proved to the complex.

13. -The internal regulation of diapause appears to be through
the liberation of hormones By either the brain, the sub
oesophageal ganglion ,or the prothoraic glands, Depending
on the species involved.
-Hormone secretion by the two latter structures may also
under control of the brain either directly by innervation,
or indirectly by hormone secretion.
-The mechanism is not at understood,the response of brain
in external stimuli Concerned with diapause .
The manner and actions are not instars later.

14. Thank you
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