complete lecture

1. 5 - 1
Tissues types and Functions
Ikramullah
Wiqarullah

2. 5 - 2
Objectives
At the end of the lecture, the students will be able to:
• Define tissue
• Explain types and functions of tissues
• Define membrane and type of membrane

3. • Introduction:
• A. Cells are arranged in tissues that provide
specific functions for the body.
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4. • B. Cells of different tissues are structured
differently, which leads to their
differences in function.
• C. The tissues of the human body include
four major types.
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5. D. These four tissue types have a
wide range of functions, as shown
in the following table.
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6. • Epithelial Tissues:
A. General Characteristics
1. Epithelial tissue is widespread
throughout the body, covers
organs, and lines body
surfaces.
2. Epithelial tissues are anchored
to a basement membrane, are
made up of tightly packed
cells containing little
intercellular material,
generally lack blood vessels,
and are replaced frequently.
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7. B. Simple Squamous Epithelium
1. Simple squamous epithelium is
made up of a single layer of
thin, flattened cells.
2. Because it is suited for
diffusion, it functions in the
exchange of gases in the
lungs and lines blood and
lymph vessels as well as body
cavities.
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9. C. Simple Cuboidal Epithelium
1. Simple cuboidal epithelium
consists of a single layer of
cube-shaped cells with
centrally located nuclei.
2. It functions in secretion and
absorption in the kidneys, and
in secretion in glands.
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11. D. Simple Columnar Epithelium
1. Simple columnar epithelium is
made up of a row of
elongated cells whose nuclei
are all located near the
basement membrane. It may
be ciliated.
2. It lines the uterus, stomach,
and intestines where it
protects underlying tissues,
secretes digestive fluids, and
absorbs nutrients.
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12. 3. In the intestine, these cells
possess microvilli that increase the
surface area available for absorption.
4. Mucus-secreting goblet cells
can be found among columnar
cells.
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13. E. Pseudo stratified Columnar Epithelium
1. These cells appear layered due to the
varying positions of their nuclei within
the row of cells, but are not truly
layered.
2. Cilia may be present, along with
mucus-secreting globlet cells, that
line and sweep debris from
respiratory tubes.
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15. F. Stratified Squamous Epithelium
1. This type of tissue is made up
of layers of flattened cells that
are designed to protect
underlying layers.
2. It makes up the outer layer of
skin, and lines the mouth,
throat, vagina, and anal canal.
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16. 3. In the skin, outer layers of cells
undergo keratinization; however, this
process does not occur where tissues remain
moist in the throat, vagina, or anal canal.
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17. G. Stratified Cuboidal Epithelium
1. This tissue consists of two to
three layers of cuboidal cells
lining a lumen of the mammary
glands, sweat glands, salivary
glands, and pancreas.
2. Several layers of cells provide
greater protection than one
single layer.
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19. H. Stratified Columnar Epithelium
1. This tissue consists of several layers
of cells and is found in the vas
deferent, part of the male urethra,
and parts of the pharynx.
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20. I. Transitional Epithelium
1. Transitional epithelium is
designed to distend and return
to its normal size, as it does in
the lining of the urinary
bladder.
2. This design provides
distensibility and keeps urine
from diffusing back into the
internal cavity.
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22. J. Glandular Epithelium
1. This tissue is made up of cells
designed to produce and
secrete substances into ducts
or into body fluids.
2. Glands that secrete products
into ducts are exocrine; those
that secrete into body fluids
and blood are called
endocrine.
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23. 3. Glands are classified by the ways
they secrete their products.
a. Merocrine glands release fluid
products by exocytosis
(pancreas) and are grouped
as serous which produce a
watery fluid or mucus which
produce a thicker, protective
substance.
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24. b. Apocrine glands lose portions
of their cell bodies during
secretion (mammary glands).
c. Holocrine glands release entire
cells (sebaceous glands).
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25. Functions of Epithelial Tissues
1. Protect:
Ex. Skin
2. Act as a barrier:
Ex. Skin keeps bacteria out
3. Diffusion and Filtration:
Ex. Lungs and kidneys
4. Secretion:
Ex. Sweat glands
5. Absorption:
Ex. Small intestine
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26. Connective Tissues:
A. General Characteristics
1. Connective tissues bind, support,
protect, serve as frameworks, fill
spaces, store fat, produce blood
cells, protect against infection,
and repair tissue damage.
2. Unlike epithelial tissues,
connective tissues have
abundant matrix, or intercellular
material, throughout, and have
good blood supplies (except
cartilage).
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27. B. Major Cell Types
1. The fibroblast is the most
common cell type, and is a
fixed, star-shaped cell that
secretes fibers and is large in
size.
2. Wandering macrophages
function as scavenger cells
and defend against infection.
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28. 3. Mast cells are large and are located
near blood vessels where they
release heparin (anticoagulant) and
histamine (promotes inflammation).
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29. C. Connective Tissue Fibers
1. Strong collagenous fibers
(white fibers), made of the
protein collagen, add strength
for holding body parts
together.
2. Elastic fibers (yellow fibers),
made of the protein elastin,
are stretchy and add flexibility
to certain types of connective
tissues.
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30. 3. Reticular fibers are thin collagenous
fibers that form supportive networks
in a variety of tissues.
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31. D. Loose Connective (areolar) Tissue
1. This type of tissue forms
delicate, thin membranes
throughout the body that bind
body parts together such as
skin and underlying organs.
2. The majority of the cells are
fibroblasts that are separated
by a gel-like ground substance
that contains collagenous and
elastic fibers.
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33. E. Adipose Tissue
1. Adipose tissue is loose
connective tissue designed to
store fat.
2. It is found beneath the skin,
around joints, padding the
kidneys and other internal
organs, and in certain
abdominal membranes.
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35. F. Dense Connective Tissue
1. This tissue consists of densely
packed collagenous fibers and
is very strong but lacks a good
blood supply.
2. It is found as part of tendons
and ligaments.
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37. G. Cartilage
1. Cartilage is a rigid connective
tissue that provides a
supportive framework for
various structures. It lacks a
vascular system and so heals
slowly.
2. Cartilage cells (chondrocytes)
lie within lacunae in the gel-
like fluid matrix.
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38. 3. Cartilaginous structures are
enclosed within a connective tissue
perichondrium.
4. The most common, hyaline
cartilage, is white with abundant
fine collagen fibers, is found at the
ends of bones, and supports
respiratory passages.
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39. 5. Elastic cartilage, with elastic fibers,
provides a framework for the
external ears and parts of the
larynx.
6. Fibrocartilage, with many
collagenous fibers, is a tough tissue
that provides a shock-absorbing
function in intervertebral disks and
in the knees and pelvic girdle.
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41. H. Bone
1. Bone is the most rigid
connective tissue, with
deposits of mineral salts and
collagen within the matrix.
2. Bone internally supports the
body, protects, forms muscle
attachments, and is the site
for blood cell formation.
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42. 3. Bone cells, called osteocytes, lie
within lacunae and are arranged in
concentric circles (osteons) around
osteonic canals interconnected by
canaliculi.
4. Bone has a good blood supply,
enabling rapid recovery after an
injury.
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44. I. Blood
1. Blood is composed of cells (red and
white) suspended in a liquid matrix
called plasma.
2. It functions to transport substances
throughout the body.
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45. Functions of Connective Tissue
1. Enclose and separate:
Ex. around organs and muscles
2. Connect tissues:
Ex. Tendons: connect bone to muscle
Ex. Ligaments: connect bone to bone
3. Support and Movement:
Ex. bones
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46. Conti………….
4. Storage:
Ex. bones store calcium and adipose tissue stores
fat
5. Cushion and insulate:
Ex. adipose tissue protects organs and helps
conserve heat
6. Transport:
Ex. Blood
7. Protect:
Ex. Immune cells
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47. Muscle Tissues:
A. General Characteristics
1. Muscle cells, or fibers, can contract
and consist of three major types.
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48. B. Skeletal Muscle Tissue
1. Skeletal muscle is attached to
bone and can be controlled by
conscious effort (voluntary).
2. The cells (muscle fibers) are
long and cylindrical, striated,
have many nuclei, and
contract from nervous
impulse.
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49. C. Smooth Muscle Tissue
1. Smooth muscle tissue lacks
striations, is uni-nucleate, and
consists of spindle-shaped
cells.
2. This involuntary muscle is
found in the walls of internal
organs, and in the digestive
tract, blood vessels, and
urinary bladder.
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50. Functions of Muscle
• Movement: Our body's skeleton gives enough rigidity to our body that skeletal
muscles can yank and pull on it, resulting in body movements such as walking, chewing,
running, lifting, manipulating objects with our hands, and picking our noses.
• Maintenance of posture: Without much conscious control, our muscles generate a
constant contractile force that allows us to maintain an erect or seated position,
or posture.
• Respiration: Our muscular system automatically drives movement of air into and out of
our body.
• Heat generation: Contraction of muscle tissue generates heat, which is essential for
maintenance of temperature homeostasis. For instance, if our core body temperature
falls, we shiver to generate more heat.
• Communication: Muscle tissue allows us to talk, gesture, write, and convey our emotional
state by doing such things as smiling or frowning.
• Constriction of organs and blood vessels: Nutrients move through our digestive tract,
urine is passed out of the body, and secretions are propelled out of glands by contraction
of smooth muscle. Constriction or relaxation of blood vessels regulates blood pressure
and blood distribution throughout the body.
• Pumping blood: Blood moves through the blood vessels because our heart tirelessly
receives blood and delivers it to all body tissues and organs.
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51. Five fun facts about the muscular system
• Muscles make up approximately 40 percent of total weight.
• The heart is the hardest-working muscle in the body. It pumps 5
quarts of blood per minute and 2,000 gallons daily.
• The gluteus maximums is the body’s largest muscle. It is in the
buttocks and helps humans maintain an upright posture.
• The ear contains the smallest muscles in the body alongside the
smallest bones. These muscles hold the inner ear together and are
connected to the eardrum.
• A muscle called the masseter in the jaw is the strongest muscle by
weight. It allows the teeth to close with a force of up to 55 pounds on
the incisors or 200 pounds on the molars.
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52. 5 - 52

53. D. Cardiac Muscle Tissue
1. Cardiac muscle tissue is found
only in the heart and consists
of branching fibers that are
connected to each other with
intercalated disks.
2. This involuntary muscle has a
single nucleus in each cell but
appears striated.
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55. Nervous Tissues:
A. Nervous tissues are found in the
brain, spinal cord, and nerves.
B. Neurons, or nerve cells, conduct
nervous impulses while helper cells,
or neuroglia, support and nourish
the neurons.
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 CopyrightThe McGraw-Hill Companies, Inc. Permission required for reproduction or display.

58. Types of Membranes
A. Serous membranes line body cavities that
lack openings to the outside.
1. They line the thorax and abdomen
and cover the organs within these
cavities.
2. Serous membranes are made up of
epithelium and loose connective
tissue and secrete serous fluid that
acts as a lubricant.
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59. B. Mucous membranes line the cavities
and openings that lead to the outside of
the body, including the oral and nasal
cavities, and openings of the digestive,
reproductive, respiratory, and urinary
systems.
1. They consist of epithelium and
connective tissue with specialized
cells that secrete mucus.
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60. C. Synovial membranes line the joint
cavities.
1. These membranes consist of only
connective tissues, and they secrete
lubricating synovial fluid.
D. The cutaneous membrane consists of
the skin (also called the integument).
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61. Thanks
?
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