Connective, Muscle and Nerve Tissue

Connective Tissues 2 Parts: 1. Cells (living) 2. Matrix (nonliving substance released by cells) A. Ground Substance B. Fiber

Connective Tissue Cells Fibroblasts – secrete molecules that make ground substances and fibers. Macrophages (Phagocytes) –part of the immune system, engulfs and digests foreign particle (only cell in the body that can move from tissue to tissue). Plasma Cells – part of the immune system, secrete antibodies. Mast Cells – produce histamines (chemicals that cause inflammation).

The Matrix The matrix is the space between the cells containing fibers and ground substance (fluid). Amount of fibers and fluids will vary. Materials in ground substances are normally clear, colorless, and similar in consistency to maple syrup. This dense consistency slows movement of bacteria and pathogens, making them easier prey for phagocytes.

Types of Connective Tissues 1.Loose Connective Tissue – more cells, few fibers (therefore they are soft)

Areolar Connective Contains fibroblasts, phagocytes, and plasma cells (which make all 3 fibers) with lots of air space. Functions: Holds organs in place Provides nutrients to and takes waste from organs Location: Everywhere

Areolar Connective

Adipose Connective Composed of adipocytes; nucleus is pushed to the side, contain large oil vacuoles. Location – under skin, around organs, behind eye, and padding for joints. Function – insulation, protection, energy storage, support and protection.

Reticular Connective Intertwined reticular fibers and cells. Location: framework of some organs (spleen) and part of bone marrow. Function: forms organs and binds smooth muscle.

2. Dense Connective Tissue - More and denser fibers, fewer cells.

Dense Connective or Dense Fibrous Few fibroblasts, predominantly collagen fibers. Location: tendons (m/b) and ligaments (b/b), lower layers of skin. Function: attachment.

3. Cartilage- Endures stress. No blood vessels or nerves. Dense network of collagen fibers and elastic. Cells - chondrocytes

Hyaline Cartilage Contains numerous chondrocytes. Location: most cartilage (ends of bones near joints,larynx, rib attachment). Function: movement, flexibility, and support.

Fibrocartilage Chondrocytes and collagen fibers. Location: in between hips and vertebrae (disks). Function: support and fusion.

Elastic Cartilage Chondrocytes and elastic fibers. Location: ear, nose. Function: maintain shape.

4. Bone (Osseous Tissue) – Bone cells (osteocytes) in cavities (lucunae) and calcified matrix

4. Bone (Osseous Tissue) – Calcified matrix

5.Blood – Liquid is plasma. Cells- RBC, WBC, and platelets