lecture day 3 connective, muscle, and nervous tissue

Connective, Muscle, and Nervous Tissue - Outline

Connective Tissues

Functions of connective tissues

·       Binding – tendons + ligaments

·       Support – cartilage

·       Protection – physical (bones protecting underlying structures) and immunity (white blood cells or leukocytes)

·       Movement – muscles attach to bones via tendons and when muscles contract it pulls the bones and causes the body to move

·       Storage – adipose tissues, bones,

·       Transport – blood

Components of connective tissue

• Types of Cells

• Fibroblasts – produces fibers + matrix (ground substance)

• Macrophages  - phagocytes (engulfs something, maybe dead epithelial cell, and breaks it down into smaller components)

• Adipocytes – contains lipids

• Mast cells – histamine (increases blood flow) and heparin (prevents blood clots)

• Lymphocytes, neutrophils, eosinophils and plasma cells

• Fibers

  • Collagen fibers – flexible, stronger than steel, long, straight, unbranched, thickest of the fibers

  • Reticular fibers – thin, branch, creates network of fibers, support for solid organs 

  • Elastic fibers – stretchable and strong, allows for stretch and recoil

Connective tissue types:

• Connective tissue proper

  • Loose connective tissue: 

    • Areolar tissue: very vascular, under epithelial and between organs, function is support cushioning   

    • Adipose tissue: under skin, around organs, absorb shock

    • Reticular tissue: function is structure + support, liver, spleen, lymph nodes, bone marrow

  • Dense connective tissue:  few blood vessels

    • Dense regular connective tissue: going the same direction, strong,

    • Dense irregular connective tissue: in bundles going different direction, durable, can support stress from multiple directions

    • Elastic tissue: stretch and recoil tissue, walls of large vessels (aorta)

• Fluid connective tissue:

  • Blood –  erythrocytes (red blood cells), leukocytes (white blood cells), thrombocytes (platelets)

  • Lymph – regulating blood volume, immune system, homeostasis

• Supporting connective tissue:

  • Cartilage – avascular

    • Chondrocytes – found in the lacunae, cells

    • lacunae – space around chondrocyte

    • perichondrium – membrane around cartilage

    • Types of cartilage

      • Hyaline cartilage: nasal cartilage

      • Elastic cartilage: has a lot of elastic fiber, flexibility, ear

      • Fibrocartilage: has a lot of collagen fibers, tough and durable,

• Bone – vascular, collagen fibers, calcium salts, calcium phosphate

• Membranes – composed of epithelium with underlying connective tissue

  • Types

    • Mucous membrane – goblet cells- mucous – remain moist, have access to external environment

    • Serous membrane  - line body cavities (pleural, peritoneal, membranes)

    • Cutaneous membrane – skin – mostly dry, water resistant, satified squamous epthelium, areolar conn. Dense irregular connective, adipose conne

    • Synovial membrane – joints, fills area within ligament between two bones with liquid

• Fasciae  

Muscle Tissue

• Functions of muscle tissue – movement,

• Types of muscle tissue

  • Skeletal – attaches to skeleton, provides movement, protection, temp regulation, voluntary movement

  • Cardiac – circulate blood, involuntary,

  • Smooth – involuntary, help blood move through blood vessels,

Nervous Tissue  

Neuron – makes electrical impulse that communicates between cells

Neuroglial or glial cell – maintains the nervous system