Lecture 4 (Connective, Muscular, Nervous Tissues) Flashcards
What are the different resident cell types present in the major classes of connective tissue?
- Immature form (-blast): Actively dividing cells that secrete the ground substance and the fibers characteristics of their particular matrix. Ex: Osteoblast
- Mature form (-cyte): Once they synthesize in the matrix, the “blast cells” assume their less active mature mode (-cyte). If the matrix is injured they revert back. Ex: Osteocyte
- Mast cells: Inflammation
- White blood cells: Immune response
- Macrophages: Large phagocytising cells
What are the 7 types of connective tissues?
- Areolar connective tissue
- Dense connective tissue
- Adipose tissue
- Elastic connective tissue
- Cartilage
- Bone tissue
- Liquid connective tissue (blood tissue and lymph)
Describe the areolar connective tissue. Where is it found?
- Most widely distributed connective tissue in body
- Contains several types of cells and all 3 types of fibers
- Location: Subcutaneous layer deep to skin, around blood vessel, nerves, organs.
Describe the adipose connective tissue. Where is it found?
- Consists of adipocytes (store fat)
- Location: wherever areolar tissue is located, subcutaneous layer deep to skin, around heart, kidneys, padding around joints
- Function: insulation, E.storage, support and protects
Describe the dense connective tissue. Where is it found?
- Contains more numerous. thicker and denser fibers (collagen) with fewer cells (fibroblasts)
- Fibers arranged in patters that provide tissue with great strength
- Location: Tendons, ligaments
- Function: provides strong attachment between structures
Describe the elastic connective tissue. Where is it found?
- Mostly elastic fibers and some fibroblasts
- Strong and can recoil to original shape
- Location: Lung tissue, arteries
- Function: allows stretching of various organs
Describe the cartilage tissue. Where is it found?
- Dense network of collagen fibers and elastic fibers
- Has no blood vessels
- Location: joints between bones, rib cage, nose, ear
- Function: support, smooth surface for movement of joints.
Describe the bone tissue. Where is it found?
- Strongest tissue formed with collagen fibers embedded with mineral deposits and osteocytes
- Location: most of the skeleton
- Functions: support and protects, allows movement (attachment of muscle), storage of calcium and phosphorous, site of blood formation.
Describe the blood type of connective tissue. Where is it found?
- Blood: Liquid ECM is the plasma (H2O, salts and dissolved proteins). No ground substance or fibers. Made of erythrocytes (red blood cells), leukocytes (white blood cells), platelets.
- Functions:
- Transportation:H2O, gases, nutrients, hormones, enzymes, heat
- Regulation: pH, temperature, H2O balance
- Protection: blood clotting, defense
What are the 3 types of muscle tissue?
- Skeletal tissue
- Smooth tissue
- Cardiac tissue
Describe the skeletal muscle tissue. Where is it found?
- Packaged by connective tissue sheets into organs called skeletal muscle.
- Voluntary movement
- Attached to bones by tendons
- Made of numerous muscle cells called muscle fibers
- Striated appearance from overlapping myosin and actin filaments.
Describe the cardiac muscle tissue. Where is it found?
- Striated with branched cells thats are joined together
- Location: contractile wall of heart
- ## Intercalated disks join cardiac muscle cells together
Describe the smooth muscle tissue. Where is it found?
- Lacks cross striations
- Spindle shaped cells
- Location: walls of bladder, digestive tract, arteries, internal organs
- Powers rhytmic, involuntary contractions commanded by the central nervous system
What is the main function of the nervous tissue?
Coordinate body activities via nerve impulses
What are the 2 types of nervous tissue? What’s the difference between the 2.
- Neurons: Nerve cells (receive input and send output to other neurons, muscle fibers or glands)
- Neuroglia: Do not generate nerve impulses (responsible for maintenance)
What are the 3 types of neuroglia? What are their functions?
- Astrocytes: support neurons, remove waste, help maintain environment
- Microglia: White blood cells of brain (clear away infection or dead cells)
- Schwann cells: Produce and maintain myelin sheath around axon of neuron
Define tissue repair
Process that replaces worn out, damaged or dead cells