ANATOMY & PHYSIOLOGY – UNIT I
CHAPTER 3: TISSUES – STRUCTURE AND FUNCTIONS
(For General Nursing & Midwifery – GNM 1st Year)
INTRODUCTION
After studying the cell, the next step is to understand tissues.
Cells do not work alone. Similar cells join together to form tissues, and tissues together form organs.
For nursing students, this chapter is very important because diseases, injuries, and healing processes involve tissues. Understanding tissues helps nurses understand wounds, inflammation, degeneration, and repair.
DEFINITION OF TISSUE
A tissue is defined as a group of similar cells performing a common function.
👉 Similar structure + common function = tissue
CLASSIFICATION OF TISSUES
The human body is made up of four basic types of tissues:
- Epithelial tissue
- Connective tissue
- Muscular tissue
- Nervous tissue
Each tissue has a specific structure, location, and function.
1. EPITHELIAL TISSUE
Definition
Epithelial tissue is a tissue that covers body surfaces, lines body cavities, and forms glands.
Characteristics of Epithelial Tissue
- Cells are closely packed
- Very little intercellular space
- No blood supply
- Cells rest on a basement membrane
- Rapid regeneration
Functions of Epithelial Tissue
- Protection (skin)
- Absorption (intestine)
- Secretion (glands)
- Excretion
- Filtration
Types of Epithelial Tissue
- Squamous epithelium
- Cuboidal epithelium
- Columnar epithelium
- Ciliated epithelium
- Glandular epithelium
2. CONNECTIVE TISSUE
Definition
Connective tissue connects, supports, binds, and protects different parts of the body.
Functions of Connective Tissue
- Support and binding
- Protection
- Transportation (blood)
- Storage (fat)
- Defense against infection
Types of Connective Tissue
a) Loose Connective Tissue
- Areolar tissue
- Adipose tissue
b) Dense Connective Tissue
- Tendons
- Ligaments
c) Specialized Connective Tissue
- Blood
- Bone
- Cartilage
3. MUSCULAR TISSUE
Definition
Muscular tissue is responsible for movement of the body and internal organs.
Characteristics of Muscular Tissue
- Contractile
- Elastic
- Excitable
Types of Muscular Tissue
a) Skeletal Muscle
- Voluntary muscle
- Attached to bones
- Helps in body movement
b) Smooth Muscle
- Involuntary muscle
- Found in internal organs
- Helps in movement of organs
c) Cardiac Muscle
- Found only in the heart
- Involuntary muscle
- Helps in pumping blood
Functions of Muscular Tissue
- Movement of body
- Maintenance of posture
- Heat production
4. NERVOUS TISSUE
Definition
Nervous tissue is specialized to receive stimuli and transmit nerve impulses.
Location
- Brain
- Spinal cord
- Nerves
Functions of Nervous Tissue
- Receives stimuli
- Conducts nerve impulses
- Controls and coordinates body activities
IMPORTANCE OF TISSUES IN NURSING
Understanding tissues helps nurses to:
- Understand wound healing
- Identify tissue damage
- Understand inflammation and infection
- Provide better patient care
KEY POINTS FOR EXAM
- Tissue = group of similar cells
- Four types of tissues
- Epithelial tissue has no blood supply
- Muscular tissue causes movement
- Nervous tissue conducts impulses
FINAL NOTE FOR STUDENTS
Do not memorize tissues blindly. Try to understand where they are found and what they do. This will help you not only in exams but also in clinical practice.