1

Animal� Tissues

Department of Zoology

The Open University of Sri Lanka

2

Content

​

• Learning Outcomes�
• Introduction

​

• Epithelial tissues

​

• Connective tissue

​

• Muscular Tissue

​

• Nervous Tissue

​

• Classification of tissues

​

​

​

​

​

3

Learning Outcomes

By the end of this session you should be able to:

​

• list the major functions of each of the four major animal

tissue types

​

• give the functions carried out by epithelial tissue types

and state their general location/s

​

• describe the basic features of connective tissue, and

explain how the cells of this tissue type enable

connective tissue to carry out its various tasks.

​

• distinguish among skeletal, cardiac, and smooth

muscle tissues in terms of location, structure, and function

• Multicellular (large) organisms function more

efficiently if cells become specialized for specific

functions.

​

• A tissue is composed of cells that function together in a

specialized activity.

​

4

Introduction

5

• There are four types of tissues found in

an animal.

​

1. Epithelial tissue

​

2. Connective tissue

​

3. Muscle tissue

​

4. Nervous tissue

Introduction

�

​

1. Epithelial tissue

​

Forming tight covering and � protecting layers below

​

​

2. Connective tissue

​

Holding other tissues

together and are surrounded by

lots of nonliving material.

​

6

7

3. Muscle tissue

​

Shortening and lengthening to

move other tissues.

​

​

4. Nervous tissue

​

Allowing rapid flow of ions

in and out to conduct

signals

1.Epithelial tissues

​

• Two types of epithelial tissues

​

1. Covering and lining epithelium ( outer layer of the

skin and some organs)

​

2. Glandular epithelium

( constitute the secreting portion of glands)

​

8

Epithelial tissues

9

• There are three types of cells in epithelial tissues

​

1. Squamous – thin flat cells

​

​

​

• Cuboidal – cells are roughly square

​

​

​

​

3.Columnar - elongated cells.

Epithelial tissues

10

• Three types of cell layers exist in epithelium tissues

11

• Glands are made up of single or a mass of epithelial

cells.

​

• Two types of glands

​

1. Exocrine - Secrete their products in to ducts

Eg . Salivary glands and mammary glands

​

2. Endocrine - Secrete their products into blood

stream

Eg. Pancreas

​

​

Glandular epithelium

​

​

​

​

Exocrine glands

Endocrine glands

​

12

Glandular epithelium

13

Functions of epithelial tissues

​

1. Provides physical protection

​

• Controls permeability

​

• Detects sensations (sight, smell , taste, equilibrium)

2. Connective tissue

​

• Most abundant and most widely distributed� tissue in the body.

​

• These tissues provide support for organs and the

body as a whole, protect and insulate internal

organs and compartmentalize structures such as

skeletal muscles, nerves.

​

​

14

15

• Connective tissue is made up of cells, ground

substances and fibers. Ground substances together

with fibers make matrix.

Connective tissue

16

Connective tissues can be classified as;

​

1. Loose connective tissue (fibers are loosely woven)

​

​

B. Dense connective tissue

(few cells among a dense network of fibers with

little ground substances)

​

​

C. Cartilage (tough but flexible)

​

Connective tissue

17

​

Blood tissue - (composed of blood cells, cell fragments and blood plasma)

Connective tissue

18

D. Bone tissue

(two types; compact and spongy)

compact – with osteons

spongy - no osteons

Connective tissue

3.Muscular Tissue

​

• Muscle cells are elongated and are called as muscle fibers

​

• These cells have main properties

​

• Excitability ( ability to respond to stimuli)

​

19

20

​

• Contractibility (ability to contract)

​

• Extensibility (ability to be stretched without tearing)

​

• Elasticity (ability to return to its normal shape)

Muscular Tissue

21

• Muscle tissue is classified into three types

(Cardiac, Skeletal and Smooth)

Muscular Tissue

• Skeletal muscles are known as striated muscles or voluntary muscles.

• These muscles are attached to bones by tendons and are responsible for skeletal movements. Basic unit of a skeletal muscle is a muscle fiber.

​

​

​

​

22

Muscular Tissue

23

​

• Cardiac muscle is unique and found only in

the wall of the heart.

​

• Its fibers have cross striations .

• This muscle is involuntary.

Cardiac muscle

Muscular Tissue

24

• Smooth muscle tissue is made up of thin elongated

muscle cells called smooth muscle fibers.

​

• These fibers are pointed at their ends and each has a

single , large oval nucleus.

• Each cell has many myofibrils which lie parallel to

one another in striated pattern , as in skeletal muscles.

Muscular Tissue

Nervous Tissue

​

• Nervous tissue is found in the brain , spinal cord and

nerves and consists of only two principal kinds of cells ,

neurons and neuroglia.

​

​

​

​

25

26

• Cells of nervous tissue have three principal parts

​

1. Dendrites

​

• Cell body

​

• Axon

Nervous Tissue

27

• Neuroglial cells that do not transmit impulses but

instead support the activities of the neurons .

​

• Schwann cells, a type in the peripheral nervous

system only in mammals.

Nervous Tissue

�

28

Squamous

Cuboidal

Columnar

Cilliated

Glandular

Areolar

Adipose

Skeletal

Fluid

Striated

Smooth

Cardiac

Tendon

​

Ligament

Bone

​

Cartilage

Blood

Lymph

29

Produced by The Open University of Sri Lanka

2014

Course Team

​

Author Web Content Developer

Mrs. W.A.Y. Chandrani Mr. Chameera Kendaragama

The Open University of Sri Lanka,

Nawala, Nugegoda.

​

OER Transformation 2014

© 2014, Open University of Sri Lanka (OUSL). OUSL OER is developed by the Centre for Educational Technology and Media. Except where otherwise noted, content on this site is licensed under a Creative Commons Attribution-Non Commercial- Share Alike 3.0 License