Question

prepare and contrast the four basic tissue types (similarities and differences)

-epithelial

-connective

-muscular

-nervous

Answer 1

The human body contains more than 200 types of cells that can all be classified into four types of tissues: epithelial, connective, muscle, and nervous. Epithelial tissues act as coverings controlling the movement of materials across the surface. Connective tissue integrates the various parts of the body and provides support and protection to organs. Muscle tissue allows the body to move. Nervous tissues propagate information.
Tissues are composed of cells similar in structure and specialized to perform a specific function for the body.
– Epithelial tissues – for lining body cavities, covering internal
organs and large surfaces.
– Connective tissues – for supporting and linking tissues or organs together; some are specialized to provide protection, to store fat, and even to provide circulatory function in the cardiovascular system.
– Muscle tissues – for providing contraction and relaxation in the body surfaces, in the heart chambers , and in hollow organs such as blood vessels and the digestive tract.
– Nerve tissue – for generating and transmitting electrical
signals (nerve impulses ) in the brain, spinal cord, and nerves.

Connective Tissue	Structure - cells (structural, immunological, defense, energy reservoirs), extracellular matrix (ground substance, protein fibers) Types of fibers - collagen, reticular, elastic Classification - proper (dense, loose), embryonic (mesenchyme, mucous), specialized (cartilage, adipose, bone, blood)
Muscle Tissue	Features - elastic, extensible, contractile Types - skeletal, cardiac (gap junctions, intercalated discs), smooth, striated, nonstriated
Nervous Tissue	Neurons - soma, dendrites, axons, ganglia (PNS), nuclei (CNS) Glia - astrocytes, oligodendrocytes, Schwann cells, microglia - blood-brain barrier

Epithelial Tissue

Features - high cellularity, special sensory receptors, forms a barrier, avascular, innervated Surfaces - basal (hemidesmosomes, basement membrane), apical (lumen, microvilli, cilia, stereocilia), lateral (adhering junctions, tight junctions, desmosomes, gap junctions) Types - squamous, cuboidal, columnar, simple, stratified, pseudostratified, specialized