5.4 Flashcards
How are connective tissue and epithelial tissue similar? How are they different?
Similarities – Both form membranes, lining cavities and surfaces.
Differences –
Epithelial – Mostly cells, avascular, forms protective barriers.
Connective – Mostly extracellular matrix, vascularized, provides support.
What are the three basic constituents of connective tissue?
Extracellular fibers, ground substance, and cells
List seven functions of connective tissue
- Forms metabolic and structural connections between other tissues.
- Forms a protective sheath around organs.
- Helps insulate the body.
- Acts as a reserve for energy.
- Provides the frame that supports the body.
- Composes the medium that transports substances from one region of the body to another.
- Plays a vital role in the healing process and in the control of invading microorganisms.
Compare and contrast collagenous, reticular, and elastic fibers
- Collagenous fibers – Thick, strong, and provide tensile strength (e.g., tendons, ligaments).
- Reticular fibers – Thin, branched, form a supportive network (e.g., lymph nodes, spleen, liver).
- Elastic fibers – Stretchy, coiled, allow flexibility (e.g., skin, lungs, blood vessel walls).
What are GAGs and what role do they play in connective tissue? Why do you suppose animals with joint injuries are sometimes given dietary supplements of GAGs?
Glycosaminoglycans (GAGs) are unbranched glycoprotein chains in soft connective tissue. They aid fiber formation during healing and may support joint recovery. Hyaluronic acid is the most common GAG in joints.
Can you give three examples of cells that are transient in connective tissue? Can you describe their form and function?
Leukocytes (white blood cells) – Large, round immune cells that move through blood vessel walls (diapedesis) to fight infections
Mast Cells – Oval-shaped with granules containing histamine and heparin, triggering inflammation.
Macrophages – Large, irregularly shaped cells that engulf microbes, dead cells, and debris for immune defense
What are fibroblasts and what role do they play in connective tissue?
Fibroblasts are fixed cells. They are large, irregularly shaped cells that manufacture and secrete both the fibers and the ground substance characteristic of their particular matrix. As the cells mature and the matrix is formed, fibroblasts adopt a less active role. If additional matrix is required later, the cells can convert back to the active form.
