The document discusses the four main types of tissues in the body: epithelial tissue, connective tissue, muscle tissue, and nervous tissue. It provides detailed information on epithelial tissue, describing the different types, functions, characteristics, and classification of epithelium. The document also discusses the structural elements, types, and examples of connective tissues. An overview of nervous tissue and the three types of muscle tissue is also provided. Finally, the document defines important anatomical terms used to describe the location and planes of the body.

1. ANATOMY AND PHYSIOLOGY
WINNIE BARAWA

2. TISSUES
The tissues of the body consist of large
numbers of cells and they are classified
according to the size, shape and functions
of these cells.
There are four main types of tissue
◦Epithelial tissue or epithelium
◦Connective tissue
◦Muscle tissue
◦Nervous tissue

3. EPITHELIAL TISSUE
 Is a sheet of cells that covers a body surface or
lines a body cavity
 It occurs in the body as
◦Covering and lining epithelium
◦Glandular epithelium
Covering and lining epithelium- forms the
outer layer of the skin, dips into and lines the
open cavities of the cardiovascular, digestive,
and respiratory systems, and covers the walls
and organs of the closed ventral body cavity.
Glandular epithelium- fashions the glands of
the body

4. Functions of epithelium
Protection
Absorption
Filtration
Excretion
Secretion
Sensory reception.

5. Special characteristics of epithelium
 Polarity -All epithelia have an apical surface, an upper
free surface exposed to the body exterior or the cavity of
an internal organ, and a lower attached basal surface.
Hence, all epithelia exhibit apical-basal polarity.
 Specialized contacts-Adjacent cells are bound
together at many points by lateral contacts, including
tight junctions and desmosomes
 Supported by connective tissue- All epithelial sheets
rest upon and are supported by connective tissue
 Avascular but innervated- Although epithelium is
innervated (supplied by nerve fibers), it is avascular
(contains no blood vessels). Epithelial cells are
nourished by substances diffusing from blood vessels in
the underlying connective tissue.
 Regeneration- Epithelium has a high regenerative
capacity, they can replace lost cells by cell division.

6. Classification of Epithelium
 Simple epithelium- are composed of a single cell
layer. They are typically found where absorption and
filtration occur and a thin epithelial barrier is desirable
 Stratified epithelium-consisting of two or more cell
layers stacked one on top of the other, are common in
high-abrasion areas where protection is important,
such as the skin surface and the lining of the mouth

8. Simple epithelium

12. Stratified epithelium

13. Stratified cuboidal epithelium- is
quite rare in the body, mostly found
in the ducts of some of the larger
glands (sweat glands, mammary
glands). It typically has two layers of
cuboidal cells.
Stratified columnar epithelium -
also has a limited distribution in the
body. Small amounts are found in
the pharynx, the male urethra, and
lining some glandular ducts

15. Glandular epithelia
 Forms glands that secrete substances
 The glands are categorized as endocrine or exocrine
depending on their mode of secretion
 Endocrine glands- they are often called ductless
glands. They produce hormones, regulatory
chemicals that they secrete by exocytosis directly into
the extracellular space. From there the hormones enter
the blood or lymphatic fluid and travel to specific target
organs
 Exocrine glands- secrete their products onto body
surfaces (skin) or into body cavities. They include
mucous, sweat, oil, and salivary glands, the liver
(which secretes bile), the pancreas (which synthesizes
digestive enzymes),

16. CONNECTIVE TISSUES
 Connects body tissues
 The main classes are
 Connective tissue proper (which includes fat and
the fibrous tissue of ligaments),
 Cartilage,
 Bone tissue
 Blood.
 Its major functions include
 Binding and support,
 Protection,
 Insulation
 Transportation of substances within the body e.g
blood

17. TYPES OF CONNECTIVE TISSUES

18. Structural Elements of Connective
Tissue
 Connective tissues have three main elements:
ground substance, fibers, and cells.
Ground-Substance
 Ground substance is the unstructured material
that fills the space between the cells and
contains the fibers.
 It is composed of interstitial (tissue) fluid, cell
adhesion proteins, and proteoglycans.
 Cell adhesion proteins (fibronectin, laminin and
others) serve mainly as a connective tissue
glue that allows connective tissue cells to
attach themselves to matrix elements.

19. Fibers
 Provide support.
 Three types of fibers are found in connective tissue
matrix: collagen, elastic, and reticular fibers.
 Collagen fibers are the strongest and most abundant.
Cells
 Each major class of connective tissue has a
fundamental cell type that exists in immature and mature
forms .
 The cells secrete ground substance and fibers
characteristic of their particular matrix.
 The primary blast cell types by connective tissue class
are
 Connective tissue proper - Fibroblast;
 Cartilage - chondroblast
 Bone- Osteoblast

20. Examples of Connective tissues

21. NERVOUS TISSUE
 Nervous tissue is the main component of the nervous
system—the brain, spinal cord, and nerves—which
regulates and controls body functions
 Neurons are highly specialized nerve cells that
generate and conduct nerve impulses
 They are branching cells with cytoplasmic extensions or
processes

22. MUSCLE TISSUE
Are highly cellular, well-vascularized
tissues that are responsible for most types
of body movement.
Muscle cells possess myofilaments,
elaborate versions of the actin and myosin
filaments that bring about movement or
contraction in all cell types.
There are three kinds of muscle tissue:
skeletal, cardiac, and smooth

23. ANATOMICAL TERMS
Anatomical position
 Is the standard reference position of the body used to
describe the location of structures
 The body is in the anatomical position when standing
upright with feet together, hands by the side and face
looking forward.
 The mouth is closed and the facial expression is neutral.
 The rim of bone under the eyes is in the same horizontal
plane as the top of the 'opening to the ear' and the eyes
are 'open' and focused on something in the distance.
 The palms of the hands face forward with the fingers
straight and together and with the pad of the thumb
turned 90° to the pads of the fingers.
 The toes point forward.

25. Anatomical planes
Three major groups of planes pass through
the body in the anatomical position
◦Coronal planes - Divide the body into
anterior and posterior parts.
◦Sagittal planes - Are at right angles to the
coronal planes and divide the body into right
and left parts.
◦Median sagittal plane (Mid-sagittal)- The
plane that passes through the center of the
body dividing it into equal right and left
halves
◦ Transverse, horizontal, or axial planes- Divide

26. Anatomical Planes

27. Terms to describe location
I.e. Anterior (ventral) and posterior (dorsal),
medial and lateral, superior and inferior
Anterior (or ventral) and posterior (or
dorsal) - describe the position of structures
relative to the 'front' and 'back' of the body.
◦ For example, the nose is an anterior (ventral)
structure whereas the vertebral column is a
posterior (dorsal) structure.
◦ Also, the nose is anterior to the ears and the
vertebral column is posterior to the sternum.

28. Medial and lateral - describe the position
of structures relative to the median sagittal
plane and the sides of the body.
 For example, the thumb is lateral to the little
finger.
 The nose is in the median sagittal plane and is
medial to the eyes, which are in turn medial to the
ears.
Superior and inferior- describe
structures in reference to the vertical axis
of the body.
 For example, the head is superior to the
shoulders and the knee joint is inferior to the hip

30. Proximal and distal, cranial and caudal,
rostral
 Other terms used to describe positions include proximal
and distal, cranial and caudal and rostral.
 Proximal and distal- are used with reference to being
closer or farther from a structure's origin, particularly in
the limbs.
 For example, the hand is distal to the elbow joint.
 Cranial (towards the head) and caudal (towards the
tail)- are sometimes used instead of superior and
inferior respectively.
 Rostral- is used, particularly in the head, to describe the
position of a structure with reference to the nose.
 For example, the forebrain is rostral to the hindbrain.