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Workbook: Body Tissues
Learning outcomes
Name the four principle tissue types
Briefly describe the main functions of each type of tissue
Discuss the general characteristics and features of muscle tissue, nervous tissue, epithelial
tissue and connective tissue
Describe the difference between simple and stratified epithelium
Compare and contrast the structure of squamous, cuboidal, columnar, ciliated, glandular,
transitional, and stratified epithelial tissue (giving examples of where in the body each
type can be found)
Relate the structure of each epithelial type to its function.
State the main function of mast cells, plasma cells, macrophages, fibroblasts, fat cells
Outline the structure, function, and location of areolar tissue, adipose tissue, fibrous
tissue, elastic tissue, hyaline cartilage, fibrocartilage, elastic fibrocartilage, bone
List and give examples of the four principle types of membrane found in the body
Name the tissues in the diagrams above.
Primary Tissues
The body is composed of 4 principle tissue types. These are:
MUSCLE
NERVOUS
EPITHELIAL
CONNECTIVE
Clinical note: The study of tissues is called histology
Organs
Organs are composed of at least two primary tissues
List four ‘vital’ organs:
BRAIN, HEART, KIDNEYS,LIVER
Systems
Organs that are located in different regions of the body and perform related functions
make up a system
List the main body systems:
Respiratory, cardiovascular, Musculoskeletal, etc etc
Muscle Tissues
Main Function: Muscle tissue is responsible for MOVEMENT
Specialized for contraction
There are 3 different types of muscle tissue. These are:
SKELETAL
CARDIAC
SMOOTH
Skeletal Muscle
Produce skeletal movement
Are these movements
Voluntary or Involuntary ?
Are the muscles
Striated or Smooth ?
Are they attached to bones by
Tendons or Ligaments?
Muscle fibers are arranged in bundles,
fibers are arranged in parallel.
Muscle cells have a
Sarcolemma and Sarcoplasm.
What are the equivalent structures in a
‘typical’ cell?
Plasma membrane and cytoplasm
What are the ‘thinnest’ structures
labelled in the diagram?
Tendons?, Muscle fibers?,
Myofibrils?, or Filaments?
(further detail on muscle to follow)
Cardiac Muscle
Striated, found only in the Heart
Using the Language of Science workbook,
look up MYOCARDIUM
Heart Muscle
Myocardial cells are interconnected
to form a ‘continuous fabric’
(further detail on the heart to follow)
Smooth Muscle
Are the muscles Striated or Smooth?
Are the movements of smooth muscle, Voluntary or Involuntary?
What two organs are in the diagram below? Digestive Tract and Eye
What sort of nerves control smooth muscle? Autonomic
As well as the smooth muscle cells, what other cell is common to both the single unit
smooth muscle and the multi-unit smooth muscle? Neurone
Where else in the body would you find smooth muscle?
Bladder, Ureters, Blood vessels, Bronchioles etc
Nervous Tissue
Main Function: Nervous tissue initiates and transmits NERVE IMPLULSES
that co-ordinate body activities
Neurones (nerve cells)
Specialized for action potential conduction.
Complete the following table:
Feature
Function
Dendrites
Receive input
Cell body
Contains the Nucleus
Nucleus
Directs cell’s activities
Axon
Conducts nerve impulses
Myelin Sheath
Increases speed of nerve impulse
Supporting cells are called neuroglia
Main Function of neuroglia is to Provide anatomical and functional support for nerve
cells
Epithelial Tissue
Main Function: Epithelial tissue or epithelium acts as Protective shield
It is found as the outer layer of the skin, lining organs, vessels etc, forms membranes
Epithelial tissue can add new cells when cells are old or worn out
Rate of renewal varies according to location
Can also be a secretory tissue
Epithelial tissue may be:
Simple, consisting of single layer of cells
Stratified, consisting of multiple layers of cells
General characteristics of Epithelial Tissues
Epithelial cells are tightly packed in continuous sheets to protect underlying tissue, or to
form barriers between systems
Cells are held in place by adhesions formed between plasma membranes of adjacent cells
The cells vary in shape and arrangement according to their function, (this forms the basis
for classifying epithelial tissue)
Cells are anchored to connective tissue by a thin layer called the …basement…
membrane.
This provides elastic support and acts as a partial barrier for diffusion and filtration
Epithelial tissue is avascular (meaning …do not have a blood supply…)
Oxygen and nutrients diffuse through the basement membrane from capillaries in the
underlying connective tissue
Structure, function and location of Epithelial Tissues: Simple
1. Squamous
Describe the cells in the diagram.
..Thin, flat, fit closely together…
..Sit on basement membrane…
……………………………………………
Function: ..Diffusion………
Location: …Alveoli, Blood Vessels etc….
2. Cuboidal
Describe the cells in the diagram.
..Cube shaped, cells fit closely together…
..Sit on basement membrane….
……………………………………………
Function: …Secretion, Absorption, Excretion….
Location: …Renal tubules, some glands.
3. Columnar
Describe the cells in the diagram.
…Rectangular shaped, microvilli, goblet cells…
…Sit on basement membrane…
……………………………………………
Function: …Absorption, secretion of mucous.
Location: …Lining of GI tract.
4. Ciliated
Describe the cells in the diagram.
…As above, with cilia…
……………………………………………
Function: …Cilia propel tube contents…….
Location: …Respiratory passages, …….
….Uterine tubes…
Structure, function, location of Epithelial Tissues: Stratified
5. Transitional
Several layers of pear shaped
Cells on a basement membrane
Function: Allows for stretching
Location: Urinary bladder
Non Keratinised Stratified
Several layers of cells
Function: Protection
Location: Found on Wet…surfaces…
subject to wear and tear, but protected from
drying out. E.g. …conjunctiva, oesophagus…
…lining of mouth……………………….…
Keratinised stratified
…Several….layers of cells
Surface layer consists of …dead..
epithelial cells to which …keratin...
has been added.
Function: .Forms tough waterproof ……
.. protective layer, prevents..
…drying out of underlying cells…
………………………………………..
Location: Found on Dry…surfaces
subject to wear and tear. E.g. …skin,……………….……
…hair, nails………………
Glands
A gland is an organ specialised to produce a substance that is sent out to other parts of the
body
The active cells of many glands are epithelial cells
Glands are divided in to two categories based on how they release their secretions
Exocrine Glands
Secretions are released through ..ducts…..
Examples:
…tear glands, sweat glands, prostate gland…….
…GI glands…………………………...
Endocrine Glands
Secrete ..hormones………… directly into
…the blood stream………
Affect ..Target………… tissues
May be discrete organs:
Examples:
…pituitary gland, thyroid gland….
………………………………………………...
Connective Tissue
Main Function: Connective tissue forms the supporting fabric of all parts of the
body, and is the most abundant, and widely distributed body tissue
Consists of two main elements: Cells and a Matrix (see diagram below)
Connective tissue: Cells
Connective tissue has different cell types that make it up
[All the cells to complete the below list are contained within the diagram]
…Fibroblasts……………….. produce collagen and elastic fibres
…Macrophages…………….. actively phagocytic
…Plasma cells………………. synthesise and secrete antibodies
…Mast cells…………………. produce histamine
…Fat cells………………..…. abundant in adipose tissue
Matrix is the non living material that exists between connective tissue cells and contains
various amounts of water, fibers, and hard minerals
A Matrix consists of fibres and ground substance (space between fibres and cells)
The various connective tissues differ in terms of hardness (depending on composition of
the Matrix)
Connective tissue is categorised according to physical properties and may be:
Liquid (Blood) or Soft or Fibrous or Hard
Most Connective tissue is highly vascular, and supplied with nerve endings
Soft connective tissue
Areolar tissue (loose)
Most common type of connective tissue
Contains cells and fibres in a loose, jelly like
background material
Function:
Connects and supports other tissues, provides
Elasticity and tensile strength
Location:
Almost everywhere.
Found in membranes around organs and
vessels, between muscles, under the skin
Question: What fibres are contained in areolar tissue?
…Collagen fibres / Elastic fibres…………………………
Adipose tissue (loose)
Each adipose cell (adipocyte) has its
cytoplasm stretched around a globule of fat
Location: widespread
Question: What is the function of
Adipose tissue??
…Reserve energy supply,………….….
……insulation……………………….
………………………………………………
……………………………………………….
Fibrous connective tissue
Fibrous tissue ca be can be regular or irregular
(see diagrams)
Very dense, contains large numbers of fibres
that give it strength and flexibility.
What are the fibres in the tissue diagrams
opposite called?…collagen fibres……….
Some types of Fibrous connective tissue contain
many elastic fibres, allowing stretch and return to
original length
What does dense regular connective
tissue contain more of?
…collagen fibres……………..
Function:
Forms the capsules surrounding certain organs
Facilitates movement
Forms the Elastic tissue in vocal chords, large
arteries, respiratory tract
Location:
Tendons and ligaments (dense regular)
Kidney, liver and glandular capsules (dense
irregular)
Hard connective tissue: Cartilage
Strong and flexible
Question: What cells produce cartilage?
…chondrocytes………………..
Question: What are the 3 types of cartilage
(one type is illustrated in the diagram opposite)>
…Fibroblasts……………………….
…Hyaline……………………………….
…Elastic………………………………….
Function: Shock absorber, and also reduces friction
between joints
Location:
Hyaline cartilage is found …end of long bones…..
Fibrocartilage is found …between vertebrae…….……..
Elastic cartilage is found …larynx, ears………….
Hard connective tissue: Bone
Produced in concentric layers or
lamellae around blood vessels.
Bone is made of oseous tissue,
(similar in structure to cartilage).
The tissue becomes impregnated
with calcium and phosphorous salts.
Question: What cells produce bone?
…osteoblasts………
Question: What are mature bone cells called?
…osteocytes…………………
Function: Support, Movement, Protection, Energy storage, Production of red and white
blood cells
Membranes
Membranes are thin sheets of tissue, there are two main types:
Epithelial membranes and Connective tissue membranes
Membranes may cover a surface, line a cavity, serve as a dividing partition, or anchor an
organ
Epithelial membranes
Mucous membranes (mucosa):
Line tubes and other body spaces that open to the environment e.g. digestive,
respiratory, reproductive tracts
Secrete mucous, a sticky fluid
Some are ciliated
Serous membranes (serosa):
Cover organs- Heart (pericardium), lungs (pleura), abdomen (peritoneum), and may
also be attacked to cavity walls
Do not connect with the outside of the body
Secrete serous fluid, allows organ to move with reduced friction
Cutaneous membranes (the skin):
Has an outer layer of epithelium
Highly complex, and will be discussed in much greater detail later on
Connective tissue membranes
Synovial membranes:
Line joint cavities
Secrete synovial fluid, that lubricates joints
Line small cushioning sacs near joints called Bursae
Other connective tissue membranes include:
Meninges surround the brain and spinal cord
Fascia fibrous bands that or sheets that support organs and hold them in place
Periosteum surrounds bones
Perichondrium surrounds cartilage