Tag: botany

Phase contrast microscopy is particularly important in biology. It reveals many cellular structures that are not visible with a simpler bright field microscope. These structures were made visible to earlier microscopists by staining, but this required additional preparation and killed the cells. The phase contrast microscope made it possible for biologists to study living cells and how they proliferate through cell division. After its invention in the early 1930s, phase contrast microscopy proved to be such an advancement in microscopy, that its inventor Frits Zernike was awarded the Nobel prize in 1953.

A fluorescence microscope is an optical microscope that uses fluorescence and phosphorescence instead of or in addition to, reflection and absorption to study properties of organic or inorganic substances. The "fluorescence microscope" refers to any microscope that uses fluorescence to generate an image, whether it is a more simple set up like an epifluorescence microscope or a more complicated design such as a confocal microscope, which uses optical sectioning to get better resolution of the fluorescent image. So, fluorescent microscope is used to localise cell structure stained with fluorochrome dyes and not for increasing resolving power, for obtaining X-ray diffraction pattern of DNA and to study cell and their components in a living state. 

The microscope is the instrument used to magnify the image of an object that we cannot see by our naked eyes. It is of two types on the basis of a number of lenses, simple microscope, and compound microscope. A light microscope is a compound microscope that uses focused light and two lenses to magnify a specimen.

The compound microscope is the instrument used to magnify the image of the object that we cannot see by naked eyes. It uses two lenses or lens systems, one is the objective lens which enlarged the image of the object and the second is an ocular lens which magnifies the image formed by the first. The total magnification is the product of the magnifications of two lens systems. Hence, the microscope which has a 10X objective lens and 10X ocular lens, it would magnify the object by 10 × 10 = 100 times. 

Antonie Philips van Leeuwenhoek was a Dutch businessman and scientist. He belonged to Holland. He discovered protozoa, a single-celled organisms. He named it as animalcules. He also had contributed in the improvement of the microscope and laid foundation for microbiology. 

In Bryophytes, archegonium is the female sex organ. The female shoot arise from the base of the male shoot and called as archegonial branch or archegoniophore. The apex of female shoot is called female receptacle from which cluster of archegonia arise intermixed with non- capitate paraphysis. 

Bryophytes are gametophyte dominant, meaning that the more prominent, longer-lived plant is the haploid gametophyte. The diploid sporophytes appear only occasionally and remain attached to and nutritionally dependent on the gametophyte.