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.
Which are plant tissues that cover the stem and the leaves? The stem perhaps covered by epidermis (having stomata, cuticle and photosynthetic cells) as in monocots or, alternat
Mineral biofortification of plants One sustainable agricultural approach to reducing the mineral deficiencies in livestock animals is to enrich major staple food crops (rice,
What is the Objectives of Neuropsychological assessment? Define and describe neuropsychological assessment; Elucidate the neuropsychological methodology for assessing i
anthropoda locomotion
Which are plant tissues that form the plant roots? Roots have a central portion called medulla made of vascular tissue outer phloem and inner xylem. Medulla is delimited by per
What are compound eyes? Arthropods have compound eyes made of many visual units called ommatidia. Every ommatidium transmits visual information by the optic nerve to the brain,
Explain about the Acesulfame K - Artificial Sweeteners? Acesulfame-K (potassium salt of 6-methyl-1, 2, 3-oxathazin-4(3H)-one 2, 2 dioxide) is a sweetener which is commonly used
Determine the Instruments that are Required For Sterilization? The word sterilization is derived from the Latin word 'Sterilic' meaning unable to produce offsprings. Sterilizat
Determine Food Sources of ascorbic acid (vitamin c)? Food sources of vitamin C include: Rich sources: Amla and guava. Good sources: Drumstick leaves, other leafy ve
On living organism Air pollution causes following effects on living organism: (a) Effects on humans: 1. Carbon monoxide reduces the oxygen carrying cap
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