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!
Problem of Polarity
The control of polarity in regenerating coelentrates like hydra has received much attention for many years. You are already aware that while a hydra is cut in half, the half with the basal disc will form a hew hypostome and the half consisting of the hypostome will generate a new basal disc. Furthermore, if a hydra is cut into various segments perpendicular to the body axis, then each middle segment will regenerate both of the a basal disc and a hypostome. So every region of the hydra can give rise to a new organism.
Yet hypostomes, as well foot does not make anywhere or at all levels along the longitudinal axis of the animal; they form just only at the distal end. This indicates that a series of gradients arise from the two poles in Hydra that is rigidly polarized along the distal proximal axis. Grafting experiments have given further evidence for the existence of gradients in the hydra. When the hypostome tissue was added to the middle region of other hydra it formed a new bud with hypostome extending outward. When the basal disc cells were likewise grafted the new bud extended to form a new pedal disc and foot. In addition if grafts of both basal disc and hypostome cells were grafted together to the gastric region no supernumerary parts made. This observation suggests which signals from opposite ends of the hydra tend to counteract each other, causing the hydra to lose its polarity. Other experiments have as well shown which normal regeneration of the hypostome can be inhibited when an intact hypostome is grafted into the body of the hydra.
Which of the following functional groups does NOT contain a carbonyl? Select one: a. Aldehyde b. Carboxyl c. Phosphate d. Amide e. Organic ester
Which of the following is not true regarding the immune response? Answer The immune response uses chemical and phagocytic cells to destroy foreign cells. Once initiated, the immune
What are the major functions of the organic molecules for living beings? Organic molecules, such as proteins, lipids and carbohydrates, perform numerous functions for living or
Selection of healing abutment It is done depending upon the tissue thickness. Tissue thickness can be measured similar to ridge mapping or sounding procedure, wherein after an
HAIR Presence of hair is main feature of mammals, absent in whale fish. Soft hair in embryo of animals are lanugo. Study of hair is tricology . Part of hair which
What is pleiotropy? Pleiotropy (or pliotropy) is the occurrence in which a single gene conditions several dissimilar phenotypical traits. Some phenotypical traits might be s
Gel shift assay is a technique by which one can determine whether a particular protein preparation contains factors which bind to the specific DNA fragment. At times when a radiol
Describe the Complete transposition of great arteries ? Lethal, relatively frequent malformation. Without treatment, it results in 30 per cent mortality within the first week o
Uses of Plural Embryos Although the basic that trigger causes polyembryony are not fully understood, there has been no dearth of interest in exploiting supernumerary embryos.
Question 1 Explain various methods employed for the lab diagnosis of rabies Definition of rabies Listing of various methods employed for rabies Explaining the meth
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