Connective tissue (CT) is a kind of biological tissue that supports, connects, or separates different types of tissues and organs of the body. It is one of the four general classes of biological tissues—the others of which are epithelial, muscular, and nervous tissues.
All CT has three main components: cells, fibers, and extracellular matrices, all immersed in the body fluids.
Nervous tissue is the main component of the two parts of the nervous system; the brain and spinal cord of the central nervous system (CNS), and the branching peripheral nerves of the peripheral nervous system (PNS), which regulates and controls bodily functions and activity. It is composed of neurons, or nerve cells, which receive and transmit impulses, and neuroglia, also known as glial cells or more commonly as just glia,(from the Greek, meaning glue) which assist the propagation of the nerve impulse as well as providing nutrients to the neuron.
Nervous tissue is made up of different types of nerve cells, all of which have an axon, the long stem like part of the cell that sends action potential signals to the next cell.
Loose connective tissue is a category of connective tissue which includes areolar tissue, reticular tissue, and adipose tissue. Loose connective tissue is the most common type of connective tissue in vertebrates. It holds organs in place and attaches epithelial tissue to other underlying tissues. It also surrounds the blood vessels and nerves. Cells called fibroblasts are widely dispersed in this tissue; they are irregular branching cells that secrete strong fibrous proteins and proteoglycans as an extracellular matrix. The cells of this type of tissue are generally separated by quite some distance by a gel-like gelatinous substance primarily made up of collagenous and elastic fibers.
Loose connective tissue is named based on the "hair weave" and type of its constituent fibers. There are three main types:
A nerve contains two types of tissue: nerve fiber and connective tissue. Dendrites and axons with Schwann cells and myelin sheath are surrounded by connective tissue. A nerve fiber in the peripheral nervous system (PNS) consists of an axon or long dendrite, myelin sheath (if existent) and their Schwann cells. Peripheral sensory fibers contain long dendrites, but peripheral motor fibers have long axons. Long dendrites of sensory fibers have structural properties as motor axons.
Science of drugs including their origin, composition, pharmacokinetics,
pharmacodynamics, therapeutic use, and toxicology.
Pharmacology (from Greek φάρμακον, pharmakon, "poison" in classic Greek; "drug" in modern Greek; and -λογία, -logia "study of", "knowledge of") is the branch of medicine and biology concerned with the study of drug action, where a drug can be broadly defined as any man-made, natural, or endogenous (within the body) molecule which exerts a biochemical and/or physiological effect on the cell, tissue, organ, or organism. More specifically, it is the study of the interactions that occur between a living organism and chemicals that affect normal or abnormal biochemical function. If substances have medicinal properties, they are considered pharmaceuticals.