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A group of similar cells that perform a specific function

A group of similar cells that perform a specific function

In multicellular animals, a group of similar cells along with

The structural organization of the human body is multi-leveled. The chemical stage, which includes tiny building blocks like atoms, is the most basic. The smallest functional units of life are cells. Single cells occur in the simplest living organisms, but cells also exist at the tissue level in complex life forms like humans.
Tissues are collections of identical cells that serve the same purpose. Epithelial, muscle, connective, and nervous tissue are the four basic tissue types. Each tissue type serves a distinct purpose in the body:
An organ is a structure that is made up of at least two different types of tissue and serves a particular purpose in the body. The liver, stomach, brain, and blood are all separate organs with distinct functions. Each organ is a specialized functional core that is in charge of a specific body function.
Complex functions are possible at the organ level thanks to the specialized activities of different tissues. Most tissues have a variety of tissue types. The stomach, for example, is made up of smooth muscle tissue for churning movement and is innervated, but it also receives blood, which is a connective tissue.

Mark the statement as true or false (a) in unicellular organisms

muscle tissue is the most common type of tissue. Controls the movement of materials within the body, such as pushing food through the digestive system. Exercising on a keyboard is an example of controlling the external motions of the whole body or portions of the body.
The nervous system…manages and coordinates all of the body’s functions. One of the body’s contact mechanisms is the nervous system. Sections of the body can’t work together smoothly if they don’t communicate.
Potential at Rest
A resting neuron’s electrical charge difference across the cell membrane, Negative charge accumulates on the inside of the membrane, while positive charge accumulates on the outside.
Synapse is a term that refers to a
The site where a neuron will send an impulse to another cell.
The axon terminal is separated from the dendrites of the neighboring cell by a gap (small cleft). Small sacs (vesicles) filled with neurotransmitters are found in terminals.
Neurotransmitters are chemical messengers in the brain.
Chemicals that a neuron uses to send a signal through a synapse to another cell. Diffuse across the chasm and attach to receptors on the neighboring cell’s membrane. Acetylcholine and norepinephrine are two examples.

Animal tissues – class 9 tutorial

A tissue is a collection of cells that perform a similar function. Differentiated cells have evolved to perform various roles in multicellular organisms such as animals. Tissues are formed when differentiated cells group together. Organs are a set of tissues that serve related functions.
Cells in multicellular organisms differentiate to perform various functions as they develop. They shape tissues as they divide into various classes. Connective tissue, muscle tissue, nervous tissue, and epithelial tissue are the four basic tissue types. Organs and organ systems are made up of many of these different tissue types. The organism is supported, protected, and strengthened by connective tissues. Skeletal muscle, smooth muscle, and cardiac muscle are the three forms of muscle tissues. Muscle tissue of all kinds contracts and relaxes to assist species in moving and functioning. Electrical and chemical signals are transmitted across the body through nervous tissue. Cells can communicate with each other thanks to these signals. Many organisms’ skin is made up of epithelial tissues, which often line the cavities of organs and organ systems. In specific species, each tissue type serves a specific purpose. Their roles are determined by the cell type and number of cells present in the tissues.

Cells tissues organs organ systems

Before you start studying the various structures and functions of the human body, it’s a good idea to think about its basic architecture, or how the body’s smallest pieces are put together to form larger structures. Subatomic particles, atoms, molecules, organelles, cells, tissues, organs, organ systems, organisms, and the biosphere ((Figure)) are useful ways to think about the body’s structures.
Scientists research the simplest building blocks of matter, subatomic particles, atoms, and molecules, to study the chemical level of organization. All matter in the universe is made up of one or more distinct pure substances known as elements, which include hydrogen, oxygen, carbon, nitrogen, calcium, and iron, to name a few. An atom is the smallest unit of all of these pure substances (elements). Protons, electrons, and neutrons are subatomic particles that make up atoms. A molecule is made up of two or more atoms, such as water molecules, proteins, and sugars found in living things. All body components are made up of molecules, which are the chemical building blocks.