Tissues
By Carlos Franco
Introduction to Tissues
• Tissue: group of similar cells that perform a
common function
• Matrix: nonliving intercellular material
• Cells combine to form four primary tissues
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Epithelial tissue
Connective tissue
Muscle tissue
Nervous tissue
Epithelial Tissue
• Two types:
– membranous epithelia
• form the coverings or linings of organs
– glandular epithelia
• form exocrine and endocrine glands
Connective Tissue
• Connects, supports, transports,
and protects other tissues and
organs
• Four main types:
• Fibrous
• Bone
• Cartilage
• Blood
Connective Tissues
1.) Fibrous
•Furnishes flexible but strong connections
2.) Bone
•Consists of bone cells (osteocytes) and a calcified cartilage matrix;
provides support and protection
3.) Cartilage
•Consists of a specialized cell (chondrocyte) embedded in a matrix
of extracellular fibers and other extracellular material
4.) Blood
•Contains blood cells, platelets, plasma; provides transportation,
homeostasis, destruction of bacteria
Muscle Tissue
• Consists of specialized cells that contract when
stimulated
• The body has three types of muscle tissue:
• Skeletal (voluntary)
• Cardiac (involuntary)
• Smooth (involuntary)
Nervous Tissue
• Functions: rapid regulation
and integration of body
activities
• Conducting cells, called
neurons, transmit impulses
from one region of the body
to another (Brain, spinal cord,
nerves)
• Non-conducting cells,
neuroglia, special connecting
and supporting cells
Tissue Repair
• Tissues have a varying capacity to repair
themselves; damaged tissue regenerates or is
replaced by scar tissue
– Regeneration: growth of new tissue
– Scar: dense fibrous mass
– Epithelial and connective tissues have the greatest
ability to regenerate
– Muscle and nervous tissues have a limited capacity to
regenerate
Body Membranes
• Body membranes: thin tissue layers that cover
surfaces, line cavities, and divide spaces or
organs
• Epithelial membranes are most common
• Connective tissue membranes:
– do not contain epithelial components
– have smooth and slick membranes
– help reduce friction between opposing surfaces in a
moveale joint
The Big Picture & Review
• Tissues and membranes maintain homeostasis
• Epithelial tissues - form membranes, absorb nutrients,
regulate body functions
• Connective tissues - hold organs and systems together
and form structures that support the body
• Muscle tissues - work with connective tissues to permit
movement
• Nervous tissues - work with glandular epithelial tissue to
regulate body function
Tissues & Their Relation to Organ Systems
• 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.