Human A&P Chapter 5
The 4 Major Tissue Types 010910wedhap 11:25
I. Epithelial II. Connective III. Muscle IV. Nervous
I. Epithelial Tissue 11:55
A word that describes a common function for all epithelial tissue is Covering.
1.Simple Squamous Epithelium 12:28
The name breaks down like this:
· Simple Single Cell Layer associated with areas where
diffusion is occurring; diffusion can occur across the surface very easily.
· Squamous – Refers to the shape of the tissue cell which is Flattened and Polyhedral (multi-sided or diamond like.)
· Epithelium – means “covering”
Simple Squamous Epithelium tissue lines the
(Lumen- or hole through each blood vessel through which
blood flows)
· Simple Squamous Epithelium tissue provides a smooth
or slick surface, or covering, which produces less drag on
blood flow.)
In this area we refer to this same tissue as “endothelium.”
And the same tissue in the heart is called “endocardium.”
There are 5 different kinds of blood vessels and
all have this tissue as an innermost lining.
are involved in the exchange of nutrients, wastes and gases
in the tissues of the blood.
They are composed wholly of Simple Squamous Epithelium
cells that loop around and form a tube.
Capillaries are very tiny blood vessels. They diffuse nutrients,
gases and waste -right across their surface.
· Simple Squamous Epithelium also form the air sacs
in the lungs which are referred to as Alveoli.
Alveoli - diffuse oxygen into the blood - out of the air that we breathe-
and carbon dioxide out of the blood -and into the air that we exhale.
· Alveoli (plural) have a little tube connected to them
called the bronchial.
· Alveola (singular) thin hollow ball ( air sac in the lungs)
· made up of thin flat cells, resembling the plates on a
soccer ball.
2. Stratified Squamous Epithelium 19:00
· Stratified means “Multiple layers” (thick)
Associated with areas where friction wears away cells at the surface
and you need to replace them from beneath.
· Forms epidermis (the outermost layer of skin)
As Stratified Squamous Epithelium cells are produced, they are alive,
down deep and as they push toward the surface, their cytoplasm is
replaced by a tough water-proof agent called keratin/ until finally
at the surface of your body these are dead cells. On the outside these
dead cells are referred to as Cornified or Horny/. It makes you
waterproof and tough; it resists physical abrasion, and builds up
as calluses on your hands and feet. It literally maintains a barrier
to keep bacteria out.
It also lines and maintains a barrier to keep bacteria out of the
mouth, portions of the pharynx (throat), anus, and the vagina.
(Friction wears away cells at the surface of all these areas.)
3. Stratified Columnar Epithelium 22:50
· Columnar – Refers to Shape
· Associated with Goblet Cells – which are (mucus secreting)
· Portions of Pharynx where mucus is needed to lubricate
for food swallowing. Also the Esophagus –needs lubrication-
as does the Anal Canal and the Male Urethra (tube leading
from the urinary bladder to the outside of the body) Without
mucus being formed inside the urethra, it would become dry
and adhesions would form where it would grow together.
4. Simple Columnar Epithelium 26:22
· Simple Single Cell Layer associated with diffusion. 26:30
· Columnar - as with all column shaped cells are
associated with mucus production.
· Line the G.I. tract between the stomach and anus.
The intestines are specifically designed to absorb nutrients
– using diffusion.
5. Simple Cuboidal Epithelium 28:04
· Simple Single Cell Layer associated with diffusion.
· Cuboidal meaning “Cubed Shaped”
· Highly Specialized - Kidney and Thyroid Glands
II. Connective Tissue (C.T.) 090110wedhap 29:43
A. Loose Connective Tissue
1. Areolar C.T.
· Attaches skin to underlying tissue (like muscle)
(The epidermis and dermis layers are stuck
together but attached loosely to the muscle
underneath to allow for movement of the
body, but returns to its original position.)
· Fills spaces between organs
· Supports blood vessels (loosely holds
veins in place)
2. Adipose Tissue “Fat” 35:00
· Energy Storage
(can be converted to A.T.P.)
· Padding
· Insulation
B. Dense Connective Tissue 35:48
1. Dense Irregular C.T. (stronger than loose c.t.)
· Irregular –Refers to the arrangement of the
fibers. Arranged in all directions- makes
tissue equally strong in all directions
· Forms the dermis layer of your skin,
resists tearing.
2. Dense Regular C.T. 37:52
· Has a parallel arrangement of fibers,
like the grain of wood which makes it
super strong but only in one direction.
· If pulled against the grain it will shred
· Forms Tendons
· Forms Ligaments
3. Elastic C.T. 41:48
· Forms Walls of Arteries (like Aorta)
· Walls of Trachea (Windpipe)
· Vocal Cords
C. Cartilage 090810wedhap 11:48
1. Hyaline Cartilage Most abundant Cartilage
in the body
· Support and Flexibility / Consistency of
rubber
· Covers the ends of bones at joints,
therefore at this area we call it
“Articular Cartilage”
· it provides a cushion between bones)
· Forms the embryonic skeleton
2. Fibro Cartilage 16:40
· Like Hyaline but has fibers
embedded in it
· Stronger / works like rebar in concrete
· Forms intervetebral discs
3. Elastic Cartilage 18:48
· Like Hyaline but has “elastic fibers”
embedded in it
· Example: External ear
Epiglottis (the seal on the Glottis)
D. Bone 21:00
Compact Bone
· Composed of Haversian Systems
or (Osteons)
· Each Haversian System, or Osteon
consists of mineral salts in concentric
rings or “Lamellae”
(la mell E’) pg160/192
Spaces between Lamellae are called Lacunae.--23:58
(la Koon-E’ ) This space is filled with Osteocytes
Pg158/195
· Small Canals“Canalicali”
(can uh leak’ uh lee) connect the
Osteocytes to the Haversian Canal
that contains blood vessels and nerves.
· Osteocytes are mature living bone cells.
They have to have a root so that nutrients &
waste can be routed to/away- via the-Haversian
Canal.
· Compact Bone is Vascular It contains
blood vessels and nerves.
E. Blood 090810wedhap 28:28
Liquid Part Solid Part
Plasma Cells and Cell fragments or
The Formed Elements” like:
· Leukocytes (White blood cell)
Fight infection
· Platelets – Involved in Blood Clotting
· Erythrocytes –o r(red blood cell)
Transport Oxygen and Carbon Dioxide
III. Muscle Tissue 30:28
There are 3 Types of Muscle Tissue
1. Skeletal Muscle
- Attached to your skeleton
- Voluntary
- Striated (Light & Dark Bands)
- Parallel fibers – pull in 1 direction
– exam. Bicep
Anytime you hear muscle fiber it means “muscle cell.”
2. Cardiac Muscle 32:25
· Associated with the Heart
· Involuntary
·
· Intercalated Discs
(hold cardiac muscle cells together)
· branching fibers pulling in multiple
directions
ex: Wicker basket & Chinese finger-cuffs
3. Smooth Muscle 34:98
· Associated with hollow internal
structure
· Involuntary
· Non-Striated
· Cells are spindle shaped
IV. Nervous Tissue 091010 no recording
1. Neurons
· Major cell type “multi-polar neuron”
–spinal cord
· Function is Communication
2. Neuroglia
§ Many types
§ Helper cells to the Neurons
