Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Threshold Value of Different Larval Tissues
Threshold value of dissimilar larval tissues for the thyroid hormone concentration
One of the main problems of metamorphosis is the co-ordination of developmental events. The tail should not degenerate till some another means of locomotion, namely the limbs develop, and the gills should not regress till the animal can employ its newly developed lung muscles. Kollros (1961) illustrated the possibility of this coordination that displays that different larval tissues have diverse threshold value for thyroxine. In other words the different larval tissues are sensitive to dissimilar concentrations of thyroid hormone.
This model is termed as the threshold concept. It has been observed that structures in the tadpole that change early during metamorphosis are more sensitive to and have low threshold value to thyroxine, than those which go through transformation at a later stage. As metamorphosis commences the thyroid hormone level slowly builds up and different events occur at different concentrations of the hormone. Experimental studies have revealed that tadpole pans that have a low threshold respond earlier during metamorphoses than those parts comprising a high threshold response. In other words, the threshold value reflects the order where metamorphic changes occur in normal development. In urodeles the bulging of eyes reacts to the weakest dose of thyroid hormone (minimum threshold) and thus is the first event in metamorphosis. This is followed by reduction of fin fold and the shortening and disappearance of external gills. After which takes place the closure of gill clefts and transformation of skin.
Design a controlled experiment to test the hypothesis that acid precipitate inhibits the growth of elodea, a common freshwater plant.
What are nutritional Care related to Neurological Disorder? Let us then move on to the nutritional care. The important goals of nutritional care are to: prevent further
Q. What are the major parts of the human ear? The human ear is divided into three major parts: the external ear, the internal ear and the middle ear.
Excretory organ of crustaceans and agama lizard
What is Peripheral Vein Feeding Intravenous feeding is a method of providing parenteral nutrition when a patient cannot take in food or formula through the gastrointestinal
Altitudinal Variations We know that temperature decreases with increasing altitude. This is mainly due to convection currents in the troposphere - the lowermost (and most dense
The major ecological imbalance on Earth is between the human species and the rest of Earth's biota. What are two specific actions we could do to achieve a balance (for example, rec
In the sarcomere of a skeletal muscle, there are A. myosin molecules in the I band. B. both tropomyosin and myosin molecules in the region of the A band that is not in the H
Determine the prevention of Cholera Prevention: Following recommendations are there to prevent cholera outbreak: Drink only water that you have boiled or treated with
Platyhelminthes (Flatworms) - Regeneration in Invertebrates Between flatworms the turbellarians, (mostly fresh water species and fresh water and terrestrial triclads) routinel
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd