From Cells to Organ Systems • Cells combine to form tissues, and tissues combine to form organs • Cells combine to form four primary tissues • Epithelial tissue • Connective tissue • Muscle tissue • Nervous tissue
Epithelium • Two types: • membranous epithelia • form the coverings or linings of organs • glandular epithelia • form exocrine and endocrine glands
Glandular Epithelia • Epithelial tissues illustrate a basic biological principle: that structure closely correlates with function
ConnectiveTissue Section 4-1 • Binds the cells and organs of the body together • All connective tissues consist of two basic components: cells and extracellular fibers • Two types of connective tissue are: • Connective tissue proper • Specialized connective tissue
Connective Tissue • An important structural component of organs • Consists of two types: • Dense connective tissue • Loose connective tissue
Specialized Connective Tissues • Perform specific functions essential to homeostasis • The body contains three types of specialized connective tissue: • Cartilage • Bone • Blood
Cartilage • Consists of specialized cells embedded in a matrix of extracellular fibers and other extracellular material • Blood • Contains blood cells, platelets, plasma
Osseous Tissue • Bone • Consists of bone cells (osteocytes) and a calcified cartilage matrix • Two types of bone tissue exist: spongy and compact
Muscle Tissue • Consists of specialized cells that contract when stimulated • The body has three types of muscle tissue: • Skeletal (voluntary) • Cardiac (involuntary) • Smooth muscle (involuntary)
Nervous Tissue • Contains specialized cells that conduct impulses • Conducting cells, called neurons, transmit impulses from one region of the body to another. • Nonconducting cells, neuroglia, are a type of nervous system connective tissue.
OrganSystems • Tissues combine to form organs. • Organs are discrete structures that have evolved to perform specific functions • Most organs do not function alone, they are part of a group of cooperative organs, called an organ system.
Let’s go to the Video Body Tissues