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Biotechnology
Diversity, structure and function of living organisms. Diversity in living organisms

Cell Biology
Cell biology (formerly called cytology, from the Greek κυτος, kytos, "vessel") and otherwise known as molecular biology, is a branch of biology that studies the different structures and functions of the cell and focuses mainly on the idea of the cell as the basic unit of life. Cell biology explains the structure, organization of the organelles they contain, their physiological properties, metabolic processes, signaling pathways, life cycle, and interactions with their environment. This is done both on a microscopic and molecular level as it encompasses prokaryotic cells and eukaryotic. Knowing the components of cells and how cells work is fundamental to all biological sciences it is also essential for research in bio-medical fields such as cancer, and other diseases. Research in cell biology is closely related to genetics, biochemistry, molecular biology, immunology, and developmental biology. Chemical and Molecular Environment
The study of the cell is done on a molecular level; however, most of the processes within the cell is made up of a mixture of small organic molecules, inorganic ions, hormones, and water. Approximately 75-85% of the cell’s volume is due to water making it an indispensable solvent as a result of its polarity and structure.^[1] These molecules within the cell, which operate as substrates, provide a suitable environment for the cell to carry out metabolic reactions and signaling. The cell shape varies among the different types of organisms, and are thus then classified into two categories: eukaryotes and prokaryotes. In the case of eukaryotic cells - which are made up of animal, plant, fungi, and protozoa cells - the shapes are generally round and spherical, while for prokaryotic cells – which are composed of bacteria and archaea - the shapes are: spherical (cocci), rods (bacillus), curved (vibrio), and spirals (spirochetes).
Cell biology focuses more on the study of eukaryotic cells, and their signaling pathways, rather than on prokaryotes, which is covered under microbiology. The main constituents of the general molecular composition of the cell includes: proteins and lipids which are either free flowing or membrane bound, along with different internal compartments known as organelles. This environment of the cell is made up of hydrophilic and hydrophobic regions, which allows for the exchange of the above-mentioned molecules and ions. The hydrophilic regions of the cell are mainly on the inside and outside of the cell, while the hydrophobic regions are within the phospholipid bilayer of the cell membrane. The cell membrane consists of lipids and proteins which accounts for its hydrophobicity as a result of being non-polar substances. Therefore, in order for these molecules to participate in reactions, within the cell, they need to be able to cross this membrane layer to get into the cell. They accomplish this process of gaining access to the cell via: osmotic pressure, diffusion, concentration gradients, and membrane channels. Inside of the cell are extensive internal sub-cellular membrane-bounded compartments called organelles.
Biotechnology
Biological techniques used to enhance products

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Biotechnology (sometimes shortened to "biotech") is a field of applied biology that involves the use of living organisms to enhance crops, biofuels, household products, and medical treatments. Modern biotechnology may involve the use of genetic engineering technology to permanently alter the genetic makeup of living organisms.
Biotechnology is the use of living systems and organisms to develop or make products, or "any technological application that uses biological systems, living organisms or derivatives thereof, to make or modify products or processes for specific use" (UN Convention on Biological Diversity, Art. 2). Depending on the tools and applications, it often overlaps with the (related) fields of bioengineering, biomedical engineering, bio manufacturing, etc.

For thousands of years, humankind has used biotechnology in agriculture, food production, and medicine.^[2] The term is largely believed to have been coined in 1919 by Hungarian engineer Károly Ereky. In the late 20th and early 21st century, biotechnology has expanded to include new and diverse sciences such as genomics, recombinant gene techniques, applied immunology, and development of pharmaceutical therapies and diagnostic tests.^[2]

Biophysics
Some of the earlier studies in biophysics were conducted in the 1840s by a group known as the Berlin school of physiologists. Among its members were pioneers such as Hermann von Helmholtz, Ernst Heinrich Weber, Carl F. W. Ludwig, and Johannes Peter Muller. Biophysics might even be seen as dating back to the studies of Luigi Galvani.

The popularity of the field rose when the book What Is Life? by Erwin Schrödinger was published. Since 1957 biophysicists have organized themselves into the Biophysical Society which now has about 9,000 members over the world.

What do biophysicists study?

Biophysicists study life at every level, from atoms and molecules to cells, organisms, and environments. As innovations come out of physics and biology labs, biophysicists find new areas to explore where they can apply their expertise, create new tools, and learn new things. The work always aims to find out how biological systems work. Biophysicists ask questions, such as:

How do protein machines work? Even though they are millions of times smaller than everyday machines, molecular machines work on the same principles. They use energy to do work. The kinesin machine shown here is carrying a load as it walks along a track. Biophysics reveals how each step is powered forward.

Reading
Diversity, structure and function of living organisms.

Diversity in living organisms
In biology, an organism is any contiguous living system, such as an animal,

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plant, fungus, archaeon, or bacterium. All known types of organisms are capable of some degree of response to stimuli, reproduction, growth and development and homeostasis. An organism consists of one or more cells; when it has one cell it is known as a unicellular organism; and when it has more than one it is known as amulticellular organism. Most unicellular organisms are of microscopic size and are thus classified as microorganisms. Humans are multicellular organisms composed of many trillions of cells grouped into specialized tissues and organs.
An organism may be either a prokaryote or a eukaryote. Prokaryotes are represented by two separate domains, the Bacteria andArchaea. Eukaryotic organisms are characterized by the presence of a membrane-bound cell nucleus and contain additional membrane-bound compartments called organelles (such as mitochondria in animals and plants and plastids in plants and algae, all generally considered to be derived from endosymbiotic bacteria).[1] Fungi, animals and plants are examples of kingdoms of organisms within the eukaryotes.

Estimates on the number of Earth’s current species range from 10 million to 14 million,[2] of which only about 1.2 million have been documented.[3] More than 99% of all species, amounting to over five billion species,[4] that ever lived on Earth are estimated to beextinct.[5][6] In July 2016, scientists reported identifying a set of 355 genes from the Last Universal Common Ancestor (LUCA) of all organisms living on Earth.[7][8]

Genus–differentia definition (Photo credit: Wikipedia)
Diversity in Living Organisms

Every living organism is unique and this uniqueness is the basis of the vast diversity displayed by the organisms in our world.

This huge diversity is the result of evolution, which has occurred over millions of years.

The massive biological diversity can only be studied by classification i.e. arranging organisms into groups based on their similarities and differences.

Different characteristics are used to determine thehierarchy of classification.

The primary characteristics that determine the broadest divisions in classification are independent of any other characteristics. The secondary characteristics depend on the primary ones.

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Prokaryotic or eukaryotic cell organization is the primary characteristic of classification, since this feature influences every detail of cell design and capacity to undertake specialized functions.

Being a unicellular or multicellular organism formsthe next basic feature of classification and causes huge differences in the body design of organisms.

The next level of classification depends on whether the organism is autotrophic or heterotrophic. Further classification depends on the various levels of organization of the bodies of these organisms.

The evolution of organisms greatly determines theirclassification.
The organisms who evolved much earlier have simple and ancient body designs whereas the recently evolved younger organisms have complexbody designs.

Older organisms are also referred to as primitive or lower organisms whereas the younger organisms are also referred to as advanced or higher organisms.

The diversity of life forms found in a region is biodiversity.
The region of mega-diversity is found in the warm and humid tropical regions of the Earth.

Aristotle classified organisms depending on their habitat.
Robert Whittaker proposed the five-kingdom scheme of classification, based on the cell structure, nutrition and body organization of the organisms.
The main characteristics considered in the five-kingdom scheme of classification are:

Presence of prokaryotic or eukaryotic cells.
If eukaryote, whether the organism is unicellular or multicellular.

“Monophyletic tree of organisms”. Ernst Haeckel: Generelle Morphologie der

Organismen, etc. Berlin, 1866. (Photo credit: Wikipedia)

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