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!
Phototropism - Root and Shoot Morphogenesis
Paratonic growth movement of part of a plant in response to light, e.g. bending of stems of indoor plants towards a window, brought about by increased elongation of cells in growth region at tip of stem on shaded side. Coleoptiles of dark grown Avena seedlings bend towards light, when we provide unilateral light. The tip is found to be playing a role. Actually the tip is site of auxin production. If the tip is removed there is no response to unilateral light. But an agar block containing auxins can substitute for the tip and coleoptile would bend towards the light as if it had not been decapitated. The coleoptile bends towards light because of unequal elongation of cells on two sides. The cells on the darker side elongate faster than those cells on two sides exposed to light.
Generally accepted that effect is due to greater concentration of auxin on dark side than on side facing light but some recent evidence suggests asymmetric distribution of some co-factor that influences auxin effect. Shoots always bend and grow towards light. It is an adaptive mechanism, no doubt. Here, also the auxin is agents that mediate light control just as in coleoptile. One question that needs to be asked is whether the extent of phototropism is proportional to the duration of exposure to light. Secondly, whether the magnitude of curvature is proportional to the energy content of the inducing light.
Metazoan Branches The Kingdom Animalia comprises all the multicellular animals (metazoans). These are divided into three branches: Mesozoa Parazoa Eumetazoa
Q. Carbohydrates requirement during myocardial infarction? The protein intake generally remains the same as per the RDI i.e. 1.0 gm protein per kg body weight per day. Adequate
How can the age of a tree be estimated from the analysis of the rings present on a cross section of its stem? For the growth of the tree it is essential to have formation of ne
Explain the Pregnancy and Obesity? Obesity is associated with increased risk for gestational diabetes, hypertension, pre- eclampsia, perinatal mortality and the need for induce
Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4
A d v a nce d vaccine technology: Genetic engineering technology is the major scientific revolution of 20th Century. This has helped in developing vaccine
mode of nutrition in zebra
Explain the Sporangiophores features of Rhizopus? 1. Sporangiophores swell at the tip into a spherical knob like structure called sporangium. It has two zones. - Central dom
PETHIDIN E - Meperidine hydrochloride. Widely used as narcotic analgesic. It has local anesthetic action. METHADON E - It is an orally effective anal
P u l l orum disease (bacillary white diarrhea) This disease is caused by poultry-adapted strain of Salmonella genus- Salmonella Pullorum and considered an important hatc
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