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!
Cell Theory
The invention of the compound microscope in the 17th century stimulated the interest in living things not visible to the naked eyes. Thus, Robert Hooke discovered 'cells' in 1665 by examining cork slices (,under a crude microscope. He was actually describing the spaces occupied by the cells limited by the cellulose walls. Hooke and his contemporaries also described cells from other plants and animals.
Figure: A generalized plant (a) and animal (b) cell. No one cell of either plant (a) or animal (b) has all the characteristics shorn in these composite figures. Both these are
However, cell theory, one of the greatest and most basic generalizations of biology, was formulated only about 200 years later. Two German investigators, Schleiden a botanist (1838), and Schwann, a zoologist (1839) are credited with presenting independently the first concise, yet comprehensive, statements about the cell. They pointed out that, "All plants and. animals are made up of small fundamental units called cells and that some organisms are unicellular and others, multicellular." Subsequent researched to the expansion of this concept by including further information on cells. We know that cells are surrounded by cell membrane and contain cytoplasm and nucleus and, most importantly, cells divide into roughly equal daughter cells by a process called cell division. Thus it became known that new cells come into existence only by the division of previously existing cells. In other words, cells do not arise by spontaneous generation from nonliving matter. It follows that all cells living today can trace their ancestry back to those which existed in ancient times.
Cyclostomes - Regeneration in Vertebrates The larvae of the lampreys between the jawless primitive fishes are able to regenerate their amputated tail. Blastema is made at the
What is Septa Septa are thin bony plates, which divide the inferior portion of the antrum into sections and may even create separate compartments. A buttress or web formation m
mode of respiration in difrent animals
THE CALORIE VALUE - The amount of heat liberated from complete combusion of 1gm food in a bomb caloriemeter (a closed metal chamber filled with O ) is its gross calorific
Q. What are respiratory pigments? What is the respiratory pigment present in some arthropods? Which is the analogous molecule in humans? Respiratory pigments are molecules able
How we explain intenal organs when we talk about symmetry??Is there any animal that is completely symmetric even insid the body?
Explain the term Lipids? If somebody discovers that you have some knowledge of nutrition, you will be promptly shooted with two questions, first, "Oh! You really can tell how m
Meaning of Behaviour Change Communication Now day's very common term used for giving health education to people and for giving information to bring change in behaviour is Behav
excretory organs of protozoa
How are platelets formed? What is the function of platelets? What consequences does the clinical condition known as thrombocytopenia yield? Platelets, also called as thrombocyt
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