What is levels of organization

Generally contains nucleic acid, cytoplasm, a cell membrane, and many other proteins and structures. Tissues : A group of similar cells with the same origin that work together to perform the same function. Level 1: Cells The first and most basic level of organization is the cellular level. Level 2: Tissues Tissues are a group of similar cells of the same origin that carry out a specific function together.

Level 3: Organs An organ is a structure made up of different tissues that perform specific bodily functions. Level 4: Organ Systems An organ system is a collection of organs that that work together to perform a similar function. Authored by : Boundless. Provided by : Boundless. Provided by : Wikiversity. Located at : en.

Provided by : Wiktionary. Provided by : Boundless Learning. Located at : www. Provided by : Wikipedia. Provided by : Wikitionary. Provided by : Wikipedia Commons. Located at : commons. Cells also contain many structures within the cytoplasm called organelles, which perform various cellular functions.

Cells may be prokaryotic without a nucleus in bacteria and archaea single-celled organisms , or eukaryotic with nucleus-enclosing DNA in plants, animals, protists, and fungi. In humans, most cells combine to form tissues, but some cells are found independent of solid tissues and have their own functions.

A red blood cell found circulating in the bloodstream carrying oxygen throughout the human body is an example of an independent cell. Tissues are a group of similar cells of the same origin that carry out a specific function together. Humans have four different types of basic tissues. Connective tissues such as bone tissue are made up of fibrous cells and give shape and structure to organs. Muscle tissue is made up of cells that can contract together and allow animals to move.

Epithelial tissues make up the outer layers of organs, such as the skin or the outer layer of the stomach. Nervous tissue is made of specialized cells that transmit information through electrochemical impulses, such as the tissue of nerves , the spinal cord , and the brain.

An organ is a structure made up of different tissues that perform specific bodily functions. Most organs contain tissues such as parenchyma used to perform the organ functions , stroma connective tissue specific to organs and epithelial. Organs may be solid or hollow, and vary considerably in size and complexity. The heart, lungs , and brain are all examples of organs. An organ system is a collection of organs that that work together to perform a similar function.

There are eleven different organ systems in the human body, each with its own specific functions. One example is digestive system, which is made up of many organs that work together to digest and absorb nutrients from food. While most organ systems control a few specific physiological processes , some processes are more complex and require multiple organ systems to work together.

Organisms are highly organized, coordinated structures that consist of one or more cells. Even very simple, single-celled organisms are remarkably complex: inside each cell, atoms make up molecules; these in turn make up cell organelles and other cellular inclusions.

In multicellular organisms, similar cells form tissues. Tissues, in turn, collaborate to create organs body structures with a distinct function. Organs work together to form organ systems. Response to Stimuli : The leaves of this sensitive plant Mimosa pudica will instantly droop and fold when touched. After a few minutes, the plant returns to normal. Organisms can respond to diverse stimuli. For example, plants can grow toward a source of light, climb on fences and walls, or respond to touch.

Even tiny bacteria can move toward or away from chemicals a process called chemotaxis or light phototaxis. Movement toward a stimulus is considered a positive response, while movement away from a stimulus is considered a negative response.

Single-celled organisms reproduce by first duplicating their DNA. They then divide it equally as the cell prepares to divide to form two new cells.

Multicellular organisms often produce specialized reproductive germline cells that will form new individuals. These genes ensure that the offspring will belong to the same species and will have similar characteristics, such as size and shape. Reproduction : Although no two look alike, these kittens have inherited genes from both parents and share many of the same characteristics.

All organisms grow and develop following specific instructions coded for by their genes. Even the smallest organisms are complex and require multiple regulatory mechanisms to coordinate internal functions, respond to stimuli, and cope with environmental stresses.

Two examples of internal functions regulated in an organism are nutrient transport and blood flow. Organs groups of tissues working together perform specific functions, such as carrying oxygen throughout the body, removing wastes, delivering nutrients to every cell, and cooling the body.

Homeostasis : Polar bears Ursus maritimus and other mammals living in ice-covered regions maintain their body temperature by generating heat and reducing heat loss through thick fur and a dense layer of fat under their skin. In order to function properly, cells need to have appropriate conditions such as proper temperature, pH, and appropriate concentration of diverse chemicals. These conditions may, however, change from one moment to the next.

For example, an organism needs to regulate body temperature through a process known as thermoregulation. Organisms that live in cold climates, such as the polar bear, have body structures that help them withstand low temperatures and conserve body heat. Structures that aid in this type of insulation include fur, feathers, blubber, and fat.

In hot climates, organisms have methods such as perspiration in humans or panting in dogs that help them to shed excess body heat. Energy Processing : The California condor Gymnogyps californianus uses chemical energy derived from food to power flight. All organisms use a source of energy for their metabolic activities. Some organisms capture energy from the sun and convert it into chemical energy in food; others use chemical energy in molecules they take in as food.

Adaptation in the flat-tailed horned lizard : This lizard exhibits a flattened body and coloring that helps camouflage it, both of which are adaptive traits that help it avoid predators. As a population of organisms interacts with the environment, individuals with traits that contribute to reproduction and survival in that particular environment will leave more offspring.

Over time those advantageous traits called adaptations will become more common in the population. This process, change over time, is called evolution, and it is one of the processes that explain the diverse species seen in biology. Adaptations help organisms survive in their ecological niches, and adaptive traits may be structural, behavioral, or physiological; as such, adaptations frequently involve other properties of organisms such as homeostasis, reproduction, and growth and development.

The biological levels of organization range from a single organelle all the way up to the biosphere in a highly structured hierarchy. Living things are highly organized and structured, following a hierarchy that can be examined on a scale from small to large. The atom is the smallest and most fundamental unit of matter. It consists of a nucleus surrounded by electrons. Atoms form molecules which are chemical structures consisting of at least two atoms held together by one or more chemical bonds.

Many molecules that are biologically important are macromolecules, large molecules that are typically formed by polymerization a polymer is a large molecule that is made by combining smaller units called monomers, which are simpler than macromolecules. An example of a macromolecule is deoxyribonucleic acid DNA , which contains the instructions for the structure and functioning of all living organisms.

Macromolecules can form aggregates within a cell that are surrounded by membranes; these are called organelles. Organelles are small structures that exist within cells.