1.What Does the Word "Cyto" Mean?

Cyto- is a combining form used like a prefix meaning "cell". It is used in a wide range of scientific terms, especially in medicine and biology.

2.What is Cytobiology ?

It is the study of the structure, function, and behavior of cells in biology. Cells are the building blocks of all living organisms. The cell is the fundamental unit of life and is responsible for the organism's survival and function. The study of the structural and functional units of the cell is known as cytobiology. Cytobiology encompasses both prokaryotic and eukaryotic cells and has numerous subtopics such as cell metabolism, cell communication, cell cycle, biochemistry, and cell composition. Cells are studied using a variety of microscopy techniques, cell culture, and cell fractionation. These techniques have enabled, and are currently being used to explore, concerns about how cells function, ultimately providing insight into the larger organism. Understanding the components of cells and how they function is essential to all biological sciences, as well as research in biomedical fields such as cancer and other diseases. Cytobiology is linked to other disciplines such as genetics, molecular genetics, molecular biology, medical microbiology, immunology, and cytochemistry.

General Structure of Cell

3.The Development of Cell Research

Cells were first seen in 17th century Europe with the invention of the compound microscope. In 1665, Robert Hooke termed the building block of all living organisms as "cells" (published in Micrographia) after looking at a piece of cork and observing a cell-like structure, however, the cells were dead and gave no indication to the actual overall components of a cell. A few years later, in 1674, Anton Van Leeuwenhoek was the first to analyze live cells in his examination of algae. All of this preceded the cell theory which states that all living things are made up of cells and that cells are the functional and structural unit of organisms. This was ultimately concluded by plant scientist, Matthias Schleiden and animal scientist Theodor Schwann in 1838, who viewed live cells in plant and animal tissue, respectively. 19 years later, Rudolf Virchow further contributed to the cell theory, adding that all cells come from the division of pre-existing cells. Viruses are not considered in cell biology – they lack the characteristics of a living cell, and instead are studied in the microbiology subclass of virology.

4.Common Techniques used to Study Cytobiology

Cell culture

Cell culture is the process by which cells are grown under controlled conditions, generally outside of their natural environment. This technique is also called micropropagation. After the cells of interest have been isolated from living tissue, they can subsequently be maintained under carefully controlled conditions the need to be kept at body temperature in an incubator. In practice, the term "cell culture" now refers to the culturing of cells derived from multicellular eukaryotes, especially animal cells, in contrast with other types of culture that also grow cells, such as plant tissue culture, fungal culture, and microbiological culture (of microbes). The historical development and methods of cell culture are closely interrelated to those of tissue culture and organ culture. Viral culture is also related, with cells as hosts for the viruses.

The use of cells grown rapidly on culture media to obtain a large number of specific cell types is an effective method for studying cells. Cell culture is one of the main tools used in cell and molecular biology and provides an excellent model system for studying the normal physiology and biochemistry of cells (e.g. metabolic studies, ageing), the effects of drugs and toxic compounds on cells, and mutagenesis and carcinogenesis. It is also used for drug screening and development, as well as for the large-scale manufacture of biological compounds (e.g. vaccines, therapeutic proteins).

Fluorescence microscopy

A fluorescence microscope is an optical microscope that uses fluorescence instead of or in addition to scattering, reflection and attenuation or absorption to study the properties of organic or inorganic substances. A "fluorescence microscope" is any microscope that uses fluorescence to produce an image, whether it is a simple setup like an epifluorescence microscope or a more complex design like a confocal microscope, which uses optical slicing to obtain better resolution of the fluorescence image. Fluorescent markers such as GFP, are used to label a specific component of the cell. Afterwards, a certain light wavelength is used to excite the fluorescent marker which can then be visualized.

Phase-contrast microscopy

Uses the optical aspect of light to represent the solid, liquid, and gas-phase changes as brightness differences.

Phase contrast microscopy (PCM) is an optical microscopy technique that converts the phase shift of light passing through a transparent specimen into a change in the brightness of the image. The phase shift itself is invisible, but becomes visible when displayed as a change in brightness.

When a light wave passes through a medium other than a vacuum, the interaction with the medium causes the amplitude and phase of the wave to change in a way that depends on the properties of the medium. The change in amplitude (brightness) comes from the scattering and absorption of light, which is usually wavelength dependent and may produce colour. Photographic equipment and the human eye are only sensitive to changes in amplitude. Therefore, without special arrangements, phase changes are invisible. However, phase changes often convey important information.

Phase contrast microscopy is particularly important in biology. It reveals many cellular structures that are not visible under bright-field microscopy, as shown in the diagram. These structures were visible under earlier microscopes by staining, but this required additional preparation and the death of cells. Phase contrast microscopy has made it possible for biologists to study living cells and how they proliferate by cell division. It is one of the few methods that does not use fluorescence to quantify cell structure and composition.

Confocal microscopy

Combines fluorescence microscopy with imaging by focusing light and snap shooting instances to form a 3-D image.

Confocal microscopy, most commonly known as confocal laser scanning microscopy (CLSM) or laser confocal scanning microscopy (LCSM), is an optical imaging technique that improves the optical resolution and contrast of micrographs by using spatial pinholes to block out-of-focus light during image formation. This technique is widely used in science and industry, with typical applications in the life sciences, semiconductor inspection and materials science.

In conventional microscopy, light travels through the sample for as long as it can penetrate the specimen, whereas confocal microscopy focuses a smaller beam of light at a narrow depth level at a time.CLSM achieves a controlled and highly limited depth of field.

Transmission electron microscopy (TEM)

Involves metal staining and the passing of electrons through the cells, which will be deflected upon interaction with metal. This ultimately forms an image of the components being studied.

TEMs find application in cancer research, virology, and materials science as well as pollution, nanotechnology and semiconductor research, but also in other fields such as paleontology and palynology. TEM is capable of returning an extraordinary variety of nanometer- and atomic-resolution information, in ideal cases revealing not only where all the atoms are but what kinds of atoms they are and how they are bonded to each other. For this reason TEM is regarded as an essential tool for nanoscience in both biological and materials fields.

Cytometry

Cytometry is the measurement of number and characteristics of cells. Variables that can be measured by cytometric methods include cell size, cell count, cell morphology (shape and structure), cell cycle phase, DNA content, and the existence or absence of specific proteins on the cell surface or in the cytoplasm. Cytometry is used to characterize and count blood cells in common blood tests such as the complete blood count. In a similar fashion, cytometry is also used in cell biology research and in medical diagnostics to characterize cells in a wide range of applications associated with diseases such as cancer and AIDS.

The cells are placed in the machine which uses a beam to scatter the cells based on different aspects and can therefore separate them based on size and content. Cells may also be tagged with GFP-fluorescence and can be separated that way as well.

Cell fractionation

This process requires breaking up the cell using high temperature or sonification followed by centrifugation to separate the parts of the cell allowing for them to be studied separately.

In cell biology, cell fractionation is the process used to separate cellular components while preserving individual functions of each component. This is a method that was originally used to demonstrate the cellular location of various biochemical processes. Other uses of subcellular fractionation is to provide an enriched source of a protein for further purification, and facilitate the diagnosis of various disease states.

References

1. Alberts, Bruce; Johnson, Alexander D.; Morgan, David; Raff, Martin; Roberts, Keith; Walter, Peter (2015). "Cells and genomes". Molecular Biology of the Cell (6th ed.). New York, NY: Garland Science. pp. 1–42. ISBN 978-0815344322.

2. Bisceglia, Nick. "Cell Biology". Scitable. www.nature.com.

3. Gupta, P. (1 December 2005). Cell and Molecular Biology. Rastogi Publications. p. 11. ISBN 978-8171338177.

4. Hooke, Robert (September 1665). Micrographia.

5. Chubb, Gilbert Charles (1911). "Cytology" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 7 (11th ed.). Cambridge University Press. p. 710.