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!
Hydra – Metazoa
The animals of phyla Cnidaria and Ctenophora are made up of only two germ layers: ectoderm which forms the outer covering of the animal and endoderm which is the inner layer and is also known as the gastroderm. However, a non-cellular jelly like substance mesoglea is present between ectoderm and endoderm which acts as a cement to bind the two layers. This layer should not be confused with the third germ layer i.e. mesoderm. Since animals of these two phyla do not have mesoderm, they are said to be diploblastic.
Figure: L.S. Hydra
If we cut a longitudinal section through 'Hydra we see two distinct layers bound together by a non-cellular mesoglea. The two germ layers give rise to many different cell types - as evident from figure. Rest of the animals (platyhelminths to mammals) are all made up of three germ layers viz. ectoderm, endoderm and mesoderm. These animals are triploblastic. If we cut a section say through a horse (a mammal and triploblastic) can we expect to see three layers like you see two layers in diploblastic Hydra? No we will net, because these three germ layers do not .remain as such, they differentiate and modify to give rise to different structures and organs in the body of the horse. The three layers will be distinct only during early embryology. Hence we call them the embryonic layers or the germ layers.
A saline drip is to be prepared for a lab experiment that is looking at hydration in lab rats. Calculate the amount of NaCl need to make 4 liters of a 0.9% solution.
Explain Eicosanoids Eicosanoids are the local hormones formed by body tissues during self-healing responses to stimuli. Eicosanoids are a family of compounds deriv
Define seliwanoff's Test or Resorcinol Hydrochloric Acid Reaction? seliwanoff's test is specific test for ketonic groups and therefore is positive for ketose sugars like fruc
History of Psychiatric Nursing: In 1873, Linda Richards, developed better nursing care in psychiatric hospitals, and organized nursing services and educational programmes in
Cleavage - Development Biology Cleavage or segmentation is a series of cell divisions of the fertilized .egg through which it is converted into a multicellular structure, call
Q. As a result of the DNA replication two DNA molecules come into existence. Why is it not correct to assert that the two "new" DNA molecules are created? What is the name given to
Q. What is Colony Collapse Disorder? Bee colonies are attacked by a variety of pathogens and parasites. One major pathogen is the acute bee paralysis virus (IAPV), which cau
Ecology is a interdisciplinary branch of science that deals with inter relationship between living organism and their environment. The term ecology (from greek, oikos-meaning ho
Phenoxyethanol is dangerous and can be absorbed through the skin - official sites for toxicity data, though, show little toxicity in man and some toxicity (irritation) with high do
Explain the term Light reflex - Neuronal pathways The neuronal pathway for light reflex can be afferent and efferent. In the afferent pathway, the pupillary fibres begin in the
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