Download Tissues – Chapter 5

Tissues – Chapter 5
Four Primary Tissues
1. Epithelial
A. Lines the body organs, cavities, and covers surfaces
B. Function: to absorb, secrete and protect
2. Connective
A. All over the body
B. Function: to support, transport and connect
3. Muscular
A. All over the body
B. Function: movement
4. Nervous
A. All over the body
B. Function: to receive and respond
I. Epithelium tissues
A. Arrangements
1. Simple – single layer
2. stratified – more than one layer
3. Pseudostratified – one layer but looks like more than one
B. Shapes
1. Squamous – irregular shape
2. Cuboidal – cube shape
3. Columnar – column shape
C. Different Types of Epithelial
1. Simple Squamous
a. single layaer of irregular – shaped cells
b. capillaries
2. Endothelium – simple squamous that lines blood vessels
3. Stratified Squamous
a. several layers of squamous cells
b. skin, mouth cavity (esophagus, tongue, throat) vagina, anal canal
4. Transitional
a. balloon like cells for stretching
b. location: ureters, urinary bladder
5. Simple cuboidal
a. single layers of cubed-shaped cells that function in secretion and absorption
b. kidney and salivary glands
6. Simple Columnar
a. single layer of column-shaped cells that function in absorption and secretion
b. location-digestive tract
c. goblet cells-specialized flask-shaped cells scattered among columnar
7. Pseudostratified Ciliated
a. looks like more than one layer but is only one
b. trachea and bronchi
8. Glandular Epithelium
A. Exocrine glands-secrete products into ducts which open to an internal or
external surface
1. tubular glands – simple tube opening to the surface
2. alveolar – sac-like openings into a duct
B. Endocrine glands – these glands secrete into tissue fluid (ductless) or
Blood
C. Types of Secretions:
1. merocrine glands – glands that release their products through the cell
membrane
Two kinds:
a. serous cells – secrete a watery substance that is high in enzymes
b. mucous cells – secrete a thick fluid called mucous
2. apocrine – when cell products are pinched off and secreted
3. holocrine – where entire cells are released filled with a product
II. Connective Tissues
A. General characteristics
1. General characteristics
1. Occurs in all parts of body
2. Binds, supports and protects
3. CT cells are further apart and there is a thick substance between them
called a matrix
4. Can reproduce
5. Some are rigid and some are loose
B. Major Cell Types
1. Fibroblast – star –shaped cells that produce:
a. white fibers made of collagen
b. yellow fibers made of elastin
2. Macrophaages – carry on phagocytosis and this clears foreign particles
3. Mast Cells
a. contain heparin – a natural blood thinner
b. contain histamine – promotes allergic reactions
C. Types of Connective Tissue
1. Loose CT
a. binds the skin to underlying tissue
b. made of fibroblast, collagen and elastin
2. Adipose
a. large cells that contain vacuoles
b. pad, insulate, and have a reserve supply of energy
3. Fibrous CT
a. contains collagen and elastin
b. makes up tendons and ligaments
c. poor supply of blood
4. Cartilage
a. provides a framework and attachment
b. Three kinds:
1. hyaline – attached to skeletal parts
2. elastic – ears and nose
3. fibrocartilage – disks between vertebrate (shock absorbers)
5. Bone
A. Most rigid and hardest due to mineral salts
B. Its origin is cartilage or membrane
C. Process by which bone hardens is called ossification
D. Function: framework
E. Basic Unit of bone is called Haversian system made of:
1. Haversian canal – the canal through which capillaries flow
2. Lacuna – contains osteocytes which are bone cells
3. Canaliculi – canals through which nutrients and gases pass to bone
cell
6. Elastic Connective Tissue
A. Made of yellow elastic fibers
B. Found in the backbone
7. Reticular Connective Tissue
A. Made of collagen fibers
B. Found in internal organ walls
8. Other Connective Tissue
A. Blood which transports.
1. plasma – fluid part
2. corpuscles – solid part
a. red blood cells – erythrocytes – carries oxygen
b. white blood cells – leukocytes – defense
c. platelet – thrombocyte – blood clotting
B. Reticuloendothelial
a. specialized cells scattered throughout the body
b. mostly marcrophages which are phagocytic
C. Lymph Tissue
a. middle man between blood and the body
b. runs parallel to the circulatory system and bathes the cells
c. lymph flow is controlled by blood pressure and body movements
III. Muscle Tissues
A. Skeletal muscle
1. voluntary
2. striations are present and are made of different concentrations of myofibrils
3. location-attachment to bones
4. function: body movement
5. nuclei along edge of the fiber
B. Smooth Muscle
1. involuntary – no control
2. no striations
3. made of single cells with nucleus
4. location – digestive organs and blood vessels
5. function: elasticity
C. Cardiac Muscle
1. involuntary
2. differs from skeletal in 3 ways:
a. nuclei are in middle
b. discs are present (discs)
3. fibers are branched
3. striations are present
4. location – heart only
5. has ability to beat without a stimulus
6. sacroplasm – protoplasm in muscle cells
7. sarcolemma – membrane around muscle
IV. Nervous Tissue
A. the basic unit is the neuron made of cell body, dendrite, and axon
B. Neuroglial cells support and bind nerve tissue