Download Chapter 4: Tissues and Membranes Theory Lecture Outline

Chapter 4: Tissues and Membranes
Theory Lecture Outline
Objectives
1. List the four main types of tissues
2. Define the function and location of tissues
3. Define the function and location of membranes
4. Define an organ and organ system
5. Relate various organs to their respective systems
6. Describe the processes involved in the two types of tissue repair
7. Describe the process of granulation
8. Define the key words that relate to this chapter
Introduction
Multicellular organisms are composed of many different types of cells. Each of these cells performs a
special function. These millions of cells are grouped according to their similarity in shape, size,
structure, intercellular materials and function. Cells so grouped are called tissues.
Tissues
• Tissues are groups of cells
A tissue is a group of cells that have similar structure and that function together as a unit. Four main
tissue types are found in the body.
• Tissue types
a. Epithelial tissue
Tissue that protects the body by covering internal and external surfaces
b. Connective tissue
Connects organs and tissue allowing for movement and provides support for other types
of tissue
c. Muscle tissue
Contains cell material which has the ability to contract and move the body
d. Nervous tissue
Contains cells that react to stimuli and conduct an impulse
Epithelial Tissue Table 4-1
Epithelial tissues are widespread throughout the body. They form a continuous layer covering of all body
surfaces, line body cavities and hollow organs, and are the major tissue in glands. They perform a variety
of functions that include protection, secretion (digestive juices, hormones, perspiration), regulation of
materials across themselves (absorption, excretion, filtration, diffusion) and sensory reception.
• Classification of epithelia.
Epithelia are classified by their function, as either mucous or serous membranes, depending on
the type of secretions produced. Epithelia are also classified according to cell shape and the
number of layers in the tissue.
• Epithelial Functions and Shapes:
a. Covering and lining tissue
1. Squamous - flat, irregularly shaped. Line the heart, blood vessels, top layer skin
2. Cuboidal- cube shaped. Line kidney tubules, ovaries, and some secretory glands.
3. Columnar- elongated and often have cilia on outer surface. Line ducts in
respiratory tract, intestines, and stomach lining.
b. Glandular or secretory tissue
1. Endocrine - form ductless glands that secrete hormones directly into bloodstream
2. Exocrine- secrete substances into ducts that are released outside the body.
Mammary glands, sweat glands, and salivary glands are examples.
Ann Senisi Scott & Elizabeth Fong: Body Structures & Functions 11th Edition
Connective Tissue Adipose Table 4-1
Connective tissues bind structures together, form a framework and support for organs and the body as a
whole, store fat, transport substances, protect against disease and help repair tissue damage; they occur
throughout the body. Connective tissues are characterized by an abundance of intercellular matrix with
relatively few cells. Connective tissue cells are able to reproduce but not as rapidly as epithelial cells.
• Classification of connective tissue
a. Adipose tissue
d. Supportive tissue
b. Areolar (loose) tissue
e. Vascular (liquid blood tissue)
c. Dense fibrous tissue
• Functions
a. Adipose tissue
1. Stores lipid (fat)
2. Acts as filler tissue
3. Cushions, supports, and insulates the body
b. Areolar (loose) tissue
1. Surrounds various organs and supports both nerve cells and blood vessels which
transport nutrient materials (to cells) and waste (away from cells)
2. Fibers embedded in areolar tissue include:
o Elastin tissue
o Collagen
c. Dense fibrous tissue
Types of dense fibrous tissue include:
1. Ligaments
Hold bones firmly together at the joints
2. Tendons
Attach skeletal muscles to the bones
3. Aponeuroses
4. Fasciae
d. Supportive tissue
1. Osseous (bone) tissue
Comprises the skeleton of the body, which supports and protects underlying soft
tissue parts and organs and also serves as attachments for skeletal muscles
2. Cartilage
o Hyaline
o Fibrocartilage
o Elastic cartilage
e. Vascular (liquid blood tissue) tissue
1. Blood
2. Lymph
Muscle Tissue Table 4-1
• Cardiac (striated involuntary)
Involuntary muscle
• Skeletal (striated voluntary)
Voluntary muscle
• Smooth (nonstriated involuntary)
Involuntary muscle
Nervous Tissue Table 4-1
• Neurons (nerve cells)
a. Irritability
Ability of nerve tissue to respond to environmental changes
Ann Senisi Scott & Elizabeth Fong: Body Structures & Functions 11th Edition
b. Conductivity
Ability to carry a nerve impulse (message)
Effects of Aging on Tissue
Aging changes are found in all of the body’s cells, tissues and organs and, in turn, effect the functioning
of the body systems.
• Cells become larger and less able to divide and reproduce
• Increase in pigments and lipids inside cell
• Waste products accumulate in the tissue
o Cell membranes change and carbon dioxide and wastes have difficulty getting out
• Connective tissue becomes progressively stiff
• Many tissues lose mass and atrophy
Membranes
• Two thin layers of tissue together form a membrane
• Membrane classification
a. Epithelial membranes
b. Connective membranes
Epithelial Membranes
Two types or classifications – mucous or serous membranes
• Mucous membranes
Mucous membranes line surfaces and spaces that lead to the outside of the body (respiratory,
digestive, reproductive and urinary) and produce a substance called mucus which lubricates and
protects the lining
a. Respiratory mucosa (lines the respiratory passages)
b. Gastric mucosa (lines the stomach)
c. Intestinal mucosa (lines the small and large intestines)
• Serous membranes (parietal and visceral)
The serous membrane is a double-walled membrane lining closed body cavities that produces a
watery fluid that allows the organs to move freely and prevents friction
a. Parietal membrane – outer part of the membrane that lines the cavity
b. Visceral membrane – part that covers the organs within
c. Types
1. Pleural membrane (lines the thoracic or chest cavity & protects the lungs)
2. Pericardial membrane (lines the heart cavity & protects the heart)
3. Peritoneal membrane (lines the abdominal cavity & protects abdominal organs)
Connective Membranes
Connective membranes consist of two layers of connective tissue
• Type or Classification
o Synovial membrane
1. Lines joint cavities
2. Secrete synovial fluid which prevents friction inside the joint cavity
Organs
• An organ is tissues grouped together to form a specific function
i.e. the stomach consists of vascular, connective, epithelial, muscular and nerve tissues
• Organs coordinate their activities to form a complete functional organism
• Organ system
o Group of organs that act together to perform a specific, related function
Ann Senisi Scott & Elizabeth Fong: Body Structures & Functions 11th Edition
Organ Systems
Table 4-2 pg. 64 (encourage students to make flash cards indicating system, system function and organs
involved)
The human body has 10 organ systems; together they coordinate their functions to form a whole, live,
functioning organism
• Skeletal
• Excretory
• Muscular
• Nervous
• Digestive
• Endocrine
• Respiratory
• Reproductive
• Circulatory
• Integumentary
Disease and Injury to Tissue
• Infection – refers to the invasion of a microorganism causing disease resulting in inflammation
• Inflammation – is a protective response to an injury or irritant resulting in pain, swelling, redness
and loss of motion
• Trauma – results from an external force causing tissue damage and injury
• Abnormal growth of cells – cause tissue damage and trauma
• Birth defects – can cause structural or functional changes of tissue
Tissue Repair
Repair of damaged tissues occurs continually during the everyday activities of living; however heart
muscle tissue does not repair itself and nerve cell bodies destroyed by infection or injury do not grow
back
• Two types of epithelial tissue repair
a. Primary repair
1. Takes place in “clean” wounds
2. Repair over a large skin area usually results in a typical scab to help in wound
healing
3. Repair of deep tissues the edges of the wound must be brought or sewn together
with sutures
b. Secondary repair
1. Repair of large open wounds with small or large tissue loss occurs through a
process called granulation
2. Granulation - forms new blood vessels surrounded by young connective tissue
and wandering cells of different types; fibroblasts will produce new collagenous
fibers; bactericidal fluid is secreted to help reduce risk of infection
•
Scar Tissue
As in any type of tissue repair, a certain amount of scar (cicatrix) tissue will form which depends
on the extent of tissue damage
o Prevent or minimize excessive scar tissue
1. Areas must be kept in alignment
2. Nutrition
3. Vitamins
Table 4-3 pg. 66
Tissue and Organ Transplant
• Blood transfusions are an example of a tissue transplant
• All transplants (tissue and organs) must be cross-matched so recipient’s immune system
won’t attack the donated organ
• Rejection is main problem in organ transplants
Ann Senisi Scott & Elizabeth Fong: Body Structures & Functions 11th Edition