Nurs 1002-Lab #3

Nurs 1002

Lab 3: Tissue, Integument, Bone Tissue

Overview

This study guide covers foundational concepts in anatomy and physiology, focusing on tissues, the integumentary system, and bone tissue. It is designed to help students understand terminology, tissue classification, and the structure and function of major tissue types.

Tissues

Introduction to Tissues

Tissues are groups of cells with similar structure and function. The study of tissues is called histology. There are four primary tissue types in the human body: epithelial, connective, muscle, and nervous tissue.

• Epithelial Tissue: Covers body surfaces and lines cavities.

• Connective Tissue: Supports, binds, and protects organs.

• Muscle Tissue: Responsible for movement.

• Nervous Tissue: Transmits electrical impulses.

Epithelial Tissue

Epithelial tissue forms boundaries between different environments and serves several key functions.

• Protection

• Absorption

• Excretion

• Filtration

• Secretion

• Sensory Reception

Epithelia are classified by:

• Number of cell layers: Simple (one layer), Stratified (two or more layers)

• Shape of cells: Squamous (flat), Cuboidal (cube-like), Columnar (tall and column-shaped)

Types of Epithelial Tissue

Type	Location	Function
Simple squamous epithelium	Air sacs of lungs, lining of heart, blood vessels, lymphatic vessels	Allows materials to pass by diffusion and filtration; secretes lubricating substances
Simple cuboidal epithelium	Ducts and secretory portions of small glands, kidney tubules	Secretion and absorption
Simple columnar epithelium	Bronchi, uterine tubes, digestive tract	Absorbs; secretes mucus and enzymes
Pseudostratified ciliated columnar epithelium	Trachea, upper respiratory tract	Secretes mucus; propels mucus by ciliary action
Stratified squamous epithelium	Esophagus, mouth, vagina, epidermis of skin	Protects against abrasion
Stratified cuboidal epithelium	Large ducts of sweat glands, mammary glands, salivary glands	Protective tissue
Stratified columnar epithelium	Male urethra, ducts of some glands	Secretes and protects
Transitional epithelium	Bladder, urethra, ureters	Stretches; allows urinary organs to expand

Glands

Glands are specialized epithelial structures that secrete substances. They are classified as either endocrine or exocrine.

• Endocrine glands: Release hormones directly into the bloodstream (e.g., thyroid, pituitary).

• Exocrine glands: Release products through ducts to body surfaces or cavities (e.g., sweat, salivary, mammary glands).

Definition: Gland is an organ or specialized tissue in the body that releases substances such as hormones, sweat, saliva, tears, milk, or digestive juices.

Comparison of Endocrine and Exocrine Glands

Feature	Endocrine Glands	Exocrine Glands
Secretion	Hormones	Enzymes, sweat, saliva, etc.
Release Method	Directly into bloodstream	Via ducts to body surface/cavity
Examples	Thyroid, pituitary	Salivary, sweat, mammary

Connective Tissue

Introduction to Connective Tissue

Connective tissue supports, binds, and protects other tissues and organs. It is the most abundant and widely distributed tissue type in the body.

• Protection

• Insulation

• Storing reserve fuel

• Transporting substances (blood)

The four main classes of connective tissue are:

• Connective tissue proper

• Cartilage

• Bone

• Blood

Muscle Tissue

Introduction to Muscle Tissue

Muscle tissue is specialized for contraction and movement. There are three types: skeletal, cardiac, and smooth muscle.

• Skeletal muscle: Voluntary, striated, attached to bones, multinucleated.

• Cardiac muscle: Involuntary, striated, found only in the heart, branching cells, usually one nucleus per cell.

• Smooth muscle: Involuntary, non-striated, found in walls of hollow organs, single nucleus per cell.

Muscle Tissue Comparison Table

Description	Skeletal Muscle	Cardiac Muscle	Smooth Muscle
Striated	X	X
Only found in the wall of the heart		X
Not striated			X
Cells are branching		X
Attached to bones	X
Cells have many nuclei	X
Under involuntary control		X	X
Found in the walls of hollow organs other than the heart			X

Integumentary System

Introduction to the Integument

The integumentary system consists of the skin and its derivatives (hair, nails, glands). It serves as a protective barrier and is involved in sensation, temperature regulation, and excretion.

Layers of the Integument

Layer	Description
Layer of the Integument	The layer of integument consists of the epidermis and dermis.
Epidermis	The epidermis is the grey layer at the top of the diagram and is the most superficial layer. It is avascular.
Dermis	The dermis is the layer underneath the epidermis that is light pink on the diagram. It is the middle and largest layer and is vascular.
Hypodermis	The hypodermis is the layer on the bottom of the diagram. It is the deepest layer and is vascular.

Key Terms and Definitions

• Integument: The skin and its accessory structures.

• Epidermis: The outermost layer of skin, composed of epithelial cells.

• Dermis: The thick layer beneath the epidermis, containing connective tissue, blood vessels, and nerves.

• Hypodermis: The deepest layer, primarily composed of adipose tissue.

Example Application

Clinical case studies often require identification of tissue types and their functions, such as recognizing the role of epithelial tissue in protection and absorption, or the importance of connective tissue in wound healing.

Additional info: Some explanations and definitions have been expanded for clarity and completeness.