What Are the Levels of Organization in Biology?
Organ, in biology, a group of tissues in a living organism that have been adapted to perform a specific function. In higher animals, organs are grouped into organ systems; e.g., the esophagus, stomach, and liver are organs of the digestive system. Learn more about organs in this article. In biology, an organ (from the Latin "organum" meaning an instrument or tool) is a collection of tissues that structurally form a functional unit specialized to perform a particular function. Your heart, kidneys, and lungs are examples of organs.
Biology is the study of life. Since life is such a broad topic, scientists break it down into several different levels of organization to make it easier to study. These levels start from the smallest unit of life and work up to the largest and most broad category. The levels, from smallest to largest, are: molecule, cell, tissue, organ, organ system, organism, population, community, ecosystem, biosphere. Wwhat are made of atoms, the smallest unit what can i eat with acid reflux symptoms chemical elements.
They can be found in all matter, living and non-living. Molecules make up the most basic structures of living beings. Two biological disciplines that focus on this level are biochemistry and molecular biology.
A cell is the basic unit of life. There are two kinds of cells : plant cells, which have a rigid cell wall made of cellulose molecules, and animal cells, which have flexible cell membranes. Cell biologists consider questions such as metabolism and other questions about structure and function within and between whah. Tissue is made of cells that work together to perform a certain task. Muscle tissue, connective tissue, and neural tissue are some types of bioology. Histologists are an example of biologists who work at this level.
An organ is a system of tissues that work together on a larger scale to do certain jobs within an animal's body. Examples how to mix durabond 90 organs are the brain, heart and lungs. Anatomy is an example of a biology specialty concerned with this level.
An organ system is a group of organs that work together to perform specific bodily functions. The respiratory system, for example, uses the lungs, airways and respiratory muscles to inhale oxygen and release carbon dioxide in animals.
Physiologists study the function of parts of the body as they work together. Though physiologists can work at any level of biological organization, they often answer questions related to organ systems. An organism is a recognizable, self-contained individual. Organisms can be unicellular organisms such as bacteria or amoebae, or multi-cellular organisms comprised of organs and organ systems. A human being is an example of a multi-cellular organism.
A population is a group of multiple organisms of the same species within a specific niology. For example, a pride waht lions in Kenya, Africa, is a population. A community consists of all the different species within a certain area. The population of lions in Kenya, plus the populations of gazelles, giraffes, elephants, dung beetles, and all other species in that area, add up to a community.
An ecosystem is made up of all the communities in a how to upload web site area, as well as all the non-living, physical components of the environment. Rocks, water and dirt are a part of an ecosystem. Ecologists may study populations, communities, or whole ecosystems. The biosphere is all of the ecosystems on Earth added together. Every animal, plant, bacteria, rock, and molecule is a part of the Earth's biosphere.
Non-biologists, such as meteorologists and geologists, may join biologists to answer questions at this level of biology organization. Nikole Yearout started writing in She writes for various websites, covering everything from marine biology to online programming and book publishing. TL;DR Too Long; Didn't Read The levels, from smallest to largest, are: molecule, cell, tissue, organ, organ system, organism, population, community, ecosystem, biosphere. How to Calculate Biologt Degrees of Freedom.
Cell Wall Composition of the Six Kingdoms. Uses of Microscopes in Science. What Are Representative Particles of Elements? What Type of Animal Is an Octopus? Levels of Classification of Microbiology. Description of an Ecosystem. What Do Volvox Eat? Summary of an Ecosystem. Main Types of Ecosystems.
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An organ is a collection of tissues joined in a structural unit to serve a common function. Organs exist in most multicellular organisms, including not only humans and other animals but also plants. In single-celled organisms such as bacteria, the functional equivalent of an organ is an organelle. An organ is made up of the same type of tissues, which are well-organized to perform specific functions in all living things, including plants, animals, birds, insects, reptiles, mammals and humans. Organs collectively form organ systems. These organs are macroscopic in structure. Mar 27, · Organ – a self-contained group of tissues that performs a specific function. Biological system – a network of entities that are biologically related; this can be on the scale of tissues or organs, but also be used on a larger scale to represent populations of living things.
An organ is a group of tissues with similar functions. Plant life and animal life rely on many organs that co-exist in organ systems. A given organ's tissues can be broadly categorized as parenchyma , the tissue peculiar to or at least archetypal of the organ and that does the organ's specialized job, and stroma , the tissues with supportive, structural, connective, or ancillary functions.
For example, in a gland , the tissue that makes the hormones is the parenchyma, whereas the stroma includes the nerves that innervate the parenchyma, the blood vessels that oxygenate and nourish it and carry away its metabolic wastes, and the connective tissues that provide a suitable place for it to be situated and anchored.
The main tissues that make up an organ tend to have common embryologic origins, such as arising from the same germ layer. Functionally related organs often cooperate to form whole organ systems.
Organs exist in most multicellular organisms. In single-celled organisms such as bacteria , the functional analogue of an organ is known as an organelle.
In plants, there are three main organs. In the study of anatomy , the term viscus refers to an internal organ. Viscera is the plural form. The number of organs in any organism depends on which precise definition of the term one uses. By one widely used definition, 79 organs have been identified in the human body.
In biology , tissue is a cellular organizational level between cells and complete organs. A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues.
The study of human and animal tissues is known as histology or, in connection with disease, histopathology. For plants, the discipline is called plant morphology. Classical tools for studying tissues include the paraffin block agarose gel is often used with plants   in which tissue is embedded and then sectioned, the histological stain , and the optical microscope.
In the last couple of decades, developments in electron microscopy , immunofluorescence , and the use of frozen tissue sections have enhanced the detail that can be observed in tissues. With these tools, the classical appearances of tissues can be examined in health and disease, enabling considerable refinement of medical diagnosis and prognosis.
Two or more organs working together in the execution of a specific body function form an organ system, also called a biological system or body system. The functions of organ systems often share significant overlap.
For instance, the nervous and endocrine system both operate via a shared organ, the hypothalamus. For this reason, the two systems are combined and studied as the neuroendocrine system.
The same is true for the musculoskeletal system because of the relationship between the muscular and skeletal systems. Common organ system designations in plants include the differentiation of shoot and root. All parts of the plant above ground in non- epiphytes , including the functionally distinct leaf and flower organs, may be classified together as the shoot organ system.
Non- placozoan animals such as humans have a variety of organ systems. These specific systems are also widely studied in human anatomy. The study of plant organs is referred to as plant morphology , rather than anatomy — as in animal systems. Organs of plants can be divided into vegetative and reproductive.
Vegetative plant organs include roots , stems , and leaves. The reproductive organs are variable. In flowering plants , they are represented by the flower , seed and fruit. In other divisions phyla of plants, the reproductive organs are called strobili , in Lycopodiophyta , or simply gametophores in mosses. The vegetative organs are essential for maintaining the life of a plant. While there can be 11 organ systems in animals, there are far fewer in plants, where some perform the vital functions, such as photosynthesis , while the reproductive organs are essential in reproduction.
However, if there is asexual vegetative reproduction , the vegetative organs are those that create the new generation of plants see clonal colony. Many societies have a system for organ donation , in which a living or deceased donor's organ is transplanted into a person with a failing organ. The transplantation of larger solid organs often requires immunosuppression to prevent organ rejection or graft-versus-host disease.
There is considerable interest throughout the world in creating laboratory-grown or artificial organs. The English word "organ" dates back to the twelfth century and refers to any musical instrument. By the late 14th century, the musical term's meaning had narrowed to refer specifically to the keyboard-based instrument. At the same time, a second meaning arose, in reference to a "body part adapted to a certain function".
Plant organs are made from tissue composed of different types of tissue. The three tissue types are ground, vascular, and dermal. The adjective visceral , also splanchnic , is used for anything pertaining to the internal organs.
Historically, viscera of animals were examined by Roman pagan priests like the haruspices or the augurs in order to divine the future by their shape, dimensions or other factors. The term "visceral" is contrasted with the term " parietal ", meaning "of or relating to the wall of a body part, organ or cavity "  The two terms are often used in describing a membrane or piece of connective tissue, referring to the opposing sides. Aristotle used the word frequently in his philosophy, both to describe the organs of plants or animals e.
Some alchemists e. Paracelsus adopted the Hermetic Qabalah assignment between the seven vital organs and the seven classical planets as follows: . The variations in natural language definitions of what constitutes an organ, their degree of precision, and the variations in how they map to ontologies and taxonomies in information science for example, to count how many organs exist in a typical human body are topics explored by writer Carl Engelking of Discover magazine in as he analyzed the science journalism coverage of the evolving scientific understanding of the mesentery.
For example, the fact that the tissues of the mesentery are continuous was something that was simply not known for sure until it was demonstrated with microscopy. However, one of the points made by an anatomist interviewed by Engelking is that, finality aside, much more could be done even now to represent existing human knowledge more clearly for computing purposes. Beginning in the 20th century  transplants began to occur as scientists knew more about the anatomy of organs.
These came later in time as procedures were often dangerous and difficult. This situation continues as long as transplantation relies upon organ donors rather than technological innovation, testing, and industrial manufacturing. The organ level of organisation in animals can be first detected in flatworms and the more derived phyla. The less-advanced taxa like Placozoa , Sponges and Radiata do not show consolidation of their tissues into organs. More complex animals are composed of different organs, which have evolved over time.
For example, the liver evolved in the stem vertebrates more than million years ago, while the gut and brain are even more ancient, arising in the ancestor of vertebrates, insects, and worms more than million years ago. Given the ancient origin of most vertebrate organs, researchers have looked for model systems, where organs have evolved more recently, and ideally have evolved multiple times independently. An outstanding model for this kind of research is the placenta , which has evolved more than times independently in vertebrates, has evolved relatively recently in some lineages, and exists in intermediate forms in extant taxa.
From Wikipedia, the free encyclopedia. Redirected from Organ biology. Collection of tissues with similar functions. For other uses, see Organs disambiguation and Viscera disambiguation. Many of the internal organs of the human body. Main article: Biological system. See also: List of organs of the human body. See also: Plant anatomy.
This section needs expansion. You can help by adding to it. February Vander's Human Physiology 12th ed. ISBN Merriam-Webster Online Dictionary. Retrieved 14 December BBC News. Retrieved Annals of Botany. ISSN PMC PMID Biology Reference. Retrieved 8 September Online Etymology Dictionary. Retrieved 22 March Biology Georgia Tech.
Georgia Tech. Biology Dictionary. February 23, Magic and Magicians in the Greco-Roman World 1 ed. Stanford University. Retrieved 23 March Organ Donor Government Web. Retrieved 19 March