Tissues Chapter 5

Tissues Four types of tissues – Epithelial – Connective – Muscle – Nervous

Epithelial Tissue General Characteristics: Found throughout the body, covers all body surfaces both inside and out. Main glandular tissue. Attached to underlying connective tissue by noncellular nonliving basement membrane. Usually has no vascular tissue - no blood supply Cells reproduce rapidly (rapid healing). Cells tightly packed together

Epithelial Cells Epithelia Tissue is named based on its description Simple – Single Layer Stratified – Multiple Layers Squamous = flat Cuboidal = square/cube Columnar = column/rectangle

Simple Squamous Function: Diffusion and filtration Found in: walls of capillaries, air sacs in lungs

Simple Cuboidal Function: Secretion and absorption Found in: kidney tubules, ducts, and ovaries

Stratified Cuboidal Epithelium Provides more protection than single layer Found in the larger ducts of glands and developing tubules

Simple Columnar Function: Secretion and Absorption Found in: Digestive tract and uterus Contains goblet cells that secret mucus Can have cilia

Stratified Squamous Functions in protection Found in skin and mouth

Basement Membranes Thin under layers of tissues, just under the epithelium The ink of tattoos must be injected below the basement membrane

Layers Tissues often come in layers Cuts that are deep enough and go through underlying tissue beneath epithelium may need stitches

Pseudostratified Columnar Single layer Nuclei are uneven and gives it a layered appearance Can have goblet cells and cilia Found in air passage linings and tubes of reproductive system

Transitional Epithelium Stretchable Blocks diffusion (no leakage) Found in urinary bladder

Glandular Epithelium Cells are specialized to produce and secrete substances Make up glands – Exocrine (sweat glands) – Endocrine (hormones)

Identify the tissues

Connective Tissues General characteristics Most abundant tissue in your body, found throughout Binds structures together Provides support, protection, framework, fills space, stores fat, produces blood cells, fights infection, and helps repair tissue Cells are scattered with abundant matrix Fluid, semi-fluid, and fibers Good blood supply

Types of Connective Tissue Mast cells (prevent clots) Macrophages (consumers) Fibroblasts (produce fibers) – Collagenous (bones, ligaments, tendons) – Elastic (respiratory)

Main types of fibers Collagenous Fibers – strong and flexible – Bones, tendons, and ligaments Elastic Fibers – Very flexible – Ears and vocal cords

Loose Connective Tissue or Areolar Tissue Binds underlying organs to skin and to each other Forms delicate thin membranes throughout the body

Loose Fibrous Connective Tissue Has space between components Occurs beneath skin and most epithelial layers Functions in support and binds organs

Adipose Tissue (fat)

Fibrous Connective Tissue Tendons = muscles to bones Ligaments = bones to bones

Dense Fibrous Connective Tissue Has collagenous fibers closely packed In dermis of skin, tendons, and ligaments Functions in support

Dense Connective Tissue Cartilage – Cartilage Cells are called Chondrocytes – Provides support and attachments – Cushions bones

Hyaline Cartilage Covers ends of joints, nose and respiratory passages

Elastic Cartilage External Ear and Larynx

Fibrocartilage Tough, shock absorbing

Bone Tissue (Osseus)

Blood Tissue

Muscle Tissue

Cardiac Muscle

Skeletal Muscle

Smooth Muscle

Nervous Tissue Neurons Neuroglia - support

Nervous Tissue Spinal Cord