Transcript Tissues – Epithelial Tissue

Tissues

Tissues – group of similar cell types that
perform a common function

The human body has four basic types of
tissue:

Epithelial

Connective

Muscle

Nervous
Tissues – Epithelial Tissue

Epithelium is tightly packed sheets of cells
that line organs and outer surfaces, as
well as the insides of hollow organs,
vessels, and body cavities.
Epithelial Tissue

Epithelia are typically anchored on one
face, but free on another

The free side is typically exposed to the
environment of body fluids

Can be single layer or many layers thick

Function in protection, secretion, and
absorption

Epithelial cells are continuously sloughing off
and are replaced by cell division
Tissues – Epithelial Tissue

Many organs are lined with epithelial tissue
Tissues – Epithelial Tissue

Many organs are lined with epithelial tissue
Simple Squamous Epithelial Tissue
– inside your cheek, skin cells
Tissues – Epithelial Tissue

Many organs are lined with epithelial tissue
Simple Cuboidal Epithelial Tissue –
kidney tubule cells
Fourth Edition
BIOLOGY
Science for Life | with Physiology
Colleen Belk • Virginia Borden Maier
© 2013 Pearson Education, Inc.
Copyright © 2009 Pearson Education, Inc.
PowerPoint Lecture prepared by
Jill Feinstein
Richland Community College
Tissues – Epithelial Tissue

Many organs are lined with epithelial tissue
Simple Columnar Epithelial Tissue –
large intestine
Tissues – Epithelial Tissue

Many organs are lined with epithelial tissue
Ciliated Pseudostratified Columar
Epithelial Tissue - trachea
Tissues– Connective Tissue
 Loosely
organized and composed of
cells embedded in a matrix
 Matrix
is composed of
protein fibers and
 ground substance

 Usually
binds organs or tissues to
one another
Tissues – Connective Tissue
 Six
different types:
Loose connective tissue
 Adipose tissue
 Blood
 Fibrous connective tissue
 Cartilage
 Bone

Tissues – Connective Tissue

Loose connective tissue

Most widespread tissue in animal body

Matrix composed of collagen and elastin fibers

It is called “loose” because of the fibers
that are loosely woven
together

Binds epithelia to tissues,
pads the skin, and holds
organs in place
Loose connective tissue
Tissues – Connective Tissue

Adipose tissue

Also called fat

Connects skin to underlying structures,
pads organs

Used for storage of energy (fat)

Primarily cells; small
amount of matrix
Adipose tissue
Tissues – Connective Tissue

Blood

Cellular component, red blood cells, white blood
cells and platelets

Matrix is the plasma

Functions include carrying oxygen and
nutrients; fighting infection
Blood
Blood
Blood
Tissues – Connective Tissue

Fibrous connective tissue

Forms tendons and ligaments

Matrix is densely packed collagen fibers
running in parallel.
Fibrous connective tissue
Nuclei of fibroblasts
Tissues – Connective Tissue

Cartilage

Cellular component  chondrocytes

Chondrocytes secrete own matrix

Cartilage cushions joints, forms
support for ears and nose

Not vascularized, so takes
a long time to heal if injured
Cartilage
Damaged Cartilage
Tissues – Connective Tissue

Bone

Rigid connective tissue

Osteoblasts secrete matrix that is composed of
collagen fibers and calcium salts

Osteocytes maintain the hardened bone matrix

Body can make use of
calcium from bones if
dietary levels are too low
Bone
Tissues – Muscle Tissue

Skeletal Muscle

Usually attached to bone

Produces all voluntary movements

Striated

Long, thin, cylindrical shape
Striated (Skeletal) Muscle Tissue
Smooth Muscle

Smooth muscle

Not striated and involuntary

Musculature of organs, blood
vessels, digestive tract

Contracts more slowly and
for longer than skeletal muscle
Cardiac Muscle
Tissues – Nervous Tissue

Neurons conduct electrical signals and
compose the cells of the brain and spinal
cord

Main functions of neurons are to:


Sense stimuli

Process stimuli

Transmit signals
Most cells of nervous system do not undergo
cell division
Tissues – Nervous Tissue
Nervous Tissue
Tissues – Tissue Donation

One person’s tissues can improve the lives
of as many as 50 people.

Injuries from motor vehicle accidents, burst
blood vessels, and drowning are common
causes of brain death.
 Once
dead, brain cells cannot recover.

Brain dead is different than being in a coma or
vegetative state.

Tissues can be treated to remove any proteins
that a person’s immune system may react to
so there is no need for donor matching.
Tissues – Tissue Donation

Types of tissues

Corneas

Eye tissue

Skin

Bones

Tendons

Veins

Heart valves