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!
Functions of Endosperm
The tissue of young endosperm is rich in food materials and various growth hormones. It regulates the precise mode of embryo development and nourishes the developing embryo. During seed germination, the reserve food materials stored in mature endosperm are digested and utilized for the growth of the seedling until the later develops chlorophyll and is able to manufacture its own food. In some plants, the seed coat and the fruit wall are consumed by the endosperm, which ultimately becomes exposed to sunlight and develops chlorophyll for photosynthesis. Rarely the outermost layer of such exposed endosperm takes on a protective function. In the absence of endosperm, the embryo usually aborts.
Endosperm development is a characteristic feature of all the families of angiosperms with the exceptions of Podostemaceae and Trapaceae. In the Orchidaceae endosperm degenerates quite early. Endosperm may be used up by the embryo as such the mature seed has no traces of it (exalbuminous seed). In most monocotyledons it persists (albuminous conditions). In the main food plants such as wheat, rice, maize and sorghum it is the starchy endosperm that forms the bulk of the grain. In many legumes the mature seed has food reserves in the cotyledons rather than in the endosperm. In the castor seed endosperm is laden with fatty substances. The cereal endosperm is made of very different tissues at maturity. The outer aleurone layer consists of living cells. The endosperm usually occupies the bulk (87%) of the grain and about 10% of the endosperm dry weight is aleurone. The aleurone layer stores lipid (about 90% of total endosperm lipid) and also contain 20% of protein. During germination, hydrolytic enzymes are produced in the aleurone layer and these are released into starchy endosperm where the reserves are hydrolysed. When the barley grains are soaked in water gibberellins (GA3 and GA1) are released from scutellum of embryo and diffuse into the endosperm.
The largest tissue for this hormone is the aleurone, which responds by breaking down its own protein reserves and by secreting enzymes (mostly hydrolytic) into the starchy endosperm. Some of these enzymes are newly synthesized (e.g. α-amylase) and some are (e.g. β-glucanase) pre-existent probably all cereals except sorghum, have aleurone that responds similarly. Thus endosperm has a very important role in the development of the embryo. In most of inter varietal and interspecific crosses, embryos fail to form because of failure of endosperm formation.
Q. What is continuous full thickness incision? 2. Continuous full - thickness incisions are indicated for a variety of situations outlined below. This type of incision may be u
Q. Why are the salt and sugar used in the production of dried fruits and dried meat? Substances that sustain a highly hypertonic environment, like salt and sugar, are used in t
What are the main classes into which the phylum is divided? What are some examples of each and in which form (polyp or medusae) are they found? Coelenterates are separated into
Define species according to the biological species concept. What two problems often make this definition impractical?
Define Requirements and Recommended Dietary Allowances (RDA)? What do we mean by requirements and RDA? The requirement level is the amount of nutrient needed to be absorbed to
Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4
Nursing Care and Treatment The only treatment is surgical repair and child may be operated before 18 months as per the choice of surgeon so that speech pattern of child may
Q What are the hyphae and the mycelium of pluricellular fungi? The major structures of pluricellular fungi are the hyphae threadlike filaments made of contiguous uni or multinu
stupidddddddddddd
Hepatitis A/B A combination vaccine containing the same antigenic components as Engerix-B and pediatric Havrix (Twinrix - GlaxoSmithKline) is available for patients >18 year
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