Unit 3 Lecture Study Guide

1. List the 4 primary tissue types and give the general characteristics and functions of each one.

Epithelial tissue covers the body surface and forms the lining for most internal cavities

Connective tissue is the most abundant and the most widely distributed of the tissues.

Muscle tissue: skeletal, smooth, and cardiac.

Nerve tissue is composed of specialized cells which not only receive stimuli but also conduct impulses to and from all parts of the body.

2. How are epithelial tissues classified? Epithelia are classified on the basis of cell shape and arrangement.

3. How does the type of epithelial tissue relate to its function? Give at least 1 example of where you would find each type of epithelial tissue. Skeletal muscle is a voluntary type of muscle tissue that is used in the contraction of skeletal parts. Smooth muscle is found in the walls of internal organs and blood vessels. It is an involuntary type. The cardiac muscle is found only in the walls of the heart and is involuntary in nature.

4. Differentiate between exocrine and endocrine glands. Give an example of each.

Endocrine glands have no ducts. They secrete what is called hormone. The hormone is released in the blood stream and is circulated in the blood where it finds a particular organ, called target organ, to which goes and influences its physiology.

Exocrine gland has duct, which is the conduit for the release of products produced by it. The product is discharged in a place where the product of the gland shows its action.

5. What is the difference between apocrine, merocrine and holocrine glands? Which is the most common?

holocrine-release their secretions by lysis of the cell.

apocrine-by budding off cell membrane into vesicles.

merocrine-by exocytosis into ducts.

6. Describe connective tissue’s intercellular material.

Fibroblasts, adipose cells, mast cells, macrophages, leukocytes and plasma cells are present in loose connective tissue. The intercellular substance (matrix) consists of fibers (collagenous, elastic, reticular), amorphous ground substance (glycoproteins, proteins, proteoglycans) and tissue fluid. Each type of C.T. has its own characteristic pattern and proportion of intercellular materials and cells; you should observe this carefully while studying your slides

7. What are the 8 main types of connective tissue? Briefly describe each.

1. Fibroblasts: The most abundant cell type, found in all connective tissues proper.

- Fibroblasts secrete proteins and the polysaccharide derivative hyaluronan (the cement which

locks cells together).

2. Macrophages (macro = large, phagein = eat): Large, amoeba-like cells of the immune system

which eat pathogens and damaged cells.

- fixed macrophages stay in the tissue.

- free macrophages migrate through tissues.

3. Adipocytes (fat cells): Each cell stores a single, large fat droplet.

4. Mesenchymal cells: Stem cells that respond to injury or infection by differentiating into

fibroblasts, macrophages or other types of cells.

5. Melanocytes: Synthesize and store the brown pigment melanin.

6. Mast cells: Release the chemicals histamine and heparin to stimulate inflammation after injury or

infection.

- basophils are mast cells carried by blood to damaged tissues.

7. Lymphocytes: Specialized immune cells carried by the lymphatic system.

- including plasma cells which produce antibodies.

8. Microphages (neutrophils and eosinophils): Phagocytic blood cells responding to chemical

signals from macrophages and mast cells

8. Order the types of connective tissue from most rigid to softest. Be sure that you understand why? bone – hyaline cartilage – loose fibrous

9. Describe the 3 types of