Rabu, 26 Oktober 2011

METAMORFOSIS BELALANG


Metamorfosis adalah suatu proses perkembangan biologi pada hewan yang melibatkan perubahan penampilan fisik dan/atau struktur setelah kelahiran atau penetasan. Perubahan fisik itu terjadi akibat pertumbuhan sel dan differensiasi sel yang secara radikal berbeda.

Metamorfosis pada dibedakan menjadi dua yaitu :

1. Metamorfosis tidak sempurna (Hemimetabola)
    Metamorfosis tidak sempurna adalah metamorfosis yang melalui tahap telur yang menetas menjadi nimfa,  

    kemudian tumbuh dan berkembang menjadi imago (dewasa).

   Nimfa adalah hewan muda yang mirip dengan hewan dewasa tetapi berukuran lebih kecil dengan  

   perbandingan tubuh yang berbeda.
   Nimfa akan mengalami molting (pergantian kulit),setiap kali setelah  
   molting mahluk hidup itu kelihatan lebih mirip dengan hewan dewasa.
   Contoh metamorfosis tidak sempurna : jangkrik, belalang, kecoa.

2. Metamorfosis sempurna (Homometabola)
    Metamorfosis sempurna adalah metamorfosis yang perkembangan individu mahluk hidup melalui tahap   

    telur–larva–pupa–imago (dewasa).
   Telur yang menetas menjadi larva dan larva akan menjadi kepompong  
    kemudian berubah menjadi imago (dewasa).
   Contoh metamorfosis sempurna : kupu-kupu.

SIKLUS METAMORFOSIS BELALANG
Telur : Belalang betina akan bertelur dan telur – telur terkandung di dalam karung berkulit keras, selalunya melebihi sepuluh, di dalam tanah atau antara daun – daun yang gugur. Setiap karung mengandungi 10 – 300 telur yang berbentuk butiran beras. Kemudian, nymph menetas dan menjadi nymph. Telur belalang boleh berada dalam keadaan dorman pada musim luruh dan sejuk, lebih kurang sepuluh bulan, bagi Negara yang mengalami empat musim.

Nymph : Sejurus selepas menetas, nymph muda (nymph instar pertama) mula memakan daun – daun tumbuhan yang lembut dan lembap. Nymph adalah versi miniatur bagi belalang dewasa, hanya ia berwarna cerah dan tidak mempunyai sayap. Nymph mengalami 5 – 6 kali proses salin kulit dan berubah bentuk dan struktur, sebelum menjadi dewasa. Peringkat ini berlaku selama 5 – 10 hari, bergantung kepada spesis dan keadaan cuaca, terutama suhu dan kelembapan. 


Dewasa : Selepas 25 – 30 hari, sayap lengkap terbentuk dan nymph menjadi matang menjadi dewasa. Tempoh masa perkembangan telur sehingga dewasa, mengambil masa 11 bulan. Belalang dewasa mencapai tempoh matang mengawan selama 15 hari dan hidup selama 30 hari. 



By: Green-Boyers.blogspot.com



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Selasa, 25 Oktober 2011

GRASSHOPPER METAMORPHOSIS




UNDERSTANDING OF METAMORPHOSIS:

Metamorphosis is a developmental process involving
  biological changes in an animal's physical appearance and
  / or structure after birth or hatching. Physical changes that
  occur due to cell growth and differentiation of cells that
  are radically different.

METAMORPHOSIS IN DIFFERENTIATED INTO TWO, NAMELY:

1. Incomplete metamorphosis (Hemimetabola)
    The metamorphosis is incomplete metamorphosis through the stages of eggs that hatch into
    nymphs, then grow and develop into imago (adult).
    Nymphs are young animals that are similar to adult  
    animals but are smaller by comparison of different body.
    Nymphs will experience a molting (change of
    skin), each time after molting creatures that look more similar to adult animals.
    Examples of incomplete metamorphosis: crickets,grasshoppers.

2. Complete metamorphosis (Homometabola Complete metamorphosis is the metamorphosis of the
    development of the individual living through the stage of egg-larva-pupa-imago (adult).
    Eggs that hatch into
    larvae and the larvae will pupate and turn into imago (adult).
    Examples of complete metamorphosis: butterfly.

THIS IS THE CYCLE OF METAMORPHOSIS GRASSHOPPER:



(‘Following are the three stages in the life cycle of grasshoppers.’)
Egg: the female grasshoppers lay the fertilized eggs in the form of egg pods, usually more than ten, either in the sand or among leaf litters. Each egg pod consists of about 10-300 eggs that are rice shaped. Then, the eggs hatch into nymphs. The eggs can remain dormant in autumn and winter seasons, for almost ten months, for the four seasons country.

Nymph: Immediately after hatching, the young nymphs (first instar nymphs) start feeding on soft and succulent plant foliages. Nymphs are miniature versions of adult grasshoppers, except that they are light in color and do not possess wings. Nymphs undergo 5-6 molts and change their form and structure, before becoming adults. The nymphal stage may last for a period of 5-10 days, based on the species and the weather condition, especially temperature and humidity. As the nymphs molt, their size increases and wing pads progressively develop on the thorax portion of the body.

Adult: After 25-30 days, the wings are developed completely and the nymphs mature into adults. Thus, by the time, an egg matures into an adult, the grasshopper is about eleven months old. The adult grasshoppers gain sexual maturity within 15 days and survive for a span of about 30 days.
The life span of grasshoppers is about 12 months. Studies have found out that the survival rate of nymphs after hatching is about 50 percent, as chances are high that they may be eaten by predators like birds, rodents and lizards. This way, grasshoppers play a major role in the effective functioning of an ecosystem, by providing food for many predators in the food chain. A swarm of grasshoppers, also known as locusts, might cause severe damages to the crops, affecting the crop yield.


By: Green-Boyers.blogspot.com

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