External Brain Assignment 3
Chapter 2: Histology
Four Types of Primary Tissues and Function
Type of Primary Tissue
Lining Epithelial Cells
-the outer layer of the skin
-the inner surface of the digestive
and respiratory cavities (Lacombe)
-the inner surface of the heart and
-the walls and the organs of the
closed ventral body
-the ducts of the exocrine
-makes up most of the glands within
-Protect underlying tissues against physical
damage, drying out, chemical injury, and
-Allows and regulates the passage of materials
(diffusion, absorption, filtration, secretion, and
excretion) into and out the deeper tissues of the
body which is what they cover or line.
Oxygen, water, food, and waste must pass
through one or more of the epithelial layers.
-Specialized parts of these form sensory parts
of the organs, such as the eye, ear, mouth (taste
buds), and nose (olfactory epithelium).
-Come from epithelial tissues that are made for
-This is usually water fluid like secretions like
salts, enzymes, hormones, mucus, fats, etc.
-Milk, insulin, bile, sweat, saliva, calcitonin,
and tears are all made by glands in the body.
-cells of tissue that are farther apart separated
by extracellular material(Lacombe)
Binding, supporting, and packaging
-hold epithelia, muscle, and neural tissue are
supported, surrounded, and held in place by it.