Human Anatomy

Introduction

Anatomical position – a common visual reference point Person stands erect with feet together and eyes

forward Palms face anteriorly with the thumbs pointed away

from the body

Regional terms – names of specific body areas Axial region – the main axis of the body Appendicular region – the limbs

Directional terminology Refers to the body in anatomical position Standardized terms of directions are paired terms

Orientation and Directional Terms

Orientation and Directional Terms

Orientation and Directional Terms

Regional Terms

Regional Terms

Body Planes and Sections

Body Planes and Sections Coronal (frontal) plane - Lies vertically

and divides body into anterior (front) and posterior (back) parts

Sagittal plane – lies vertically and divides the body into left and right sides.Median (midsagittal) plane - Specific sagittal

plane that lies vertically in the midline Transverse plane - runs horizontally and

divides body into superior (up) and inferior (down) parts

Figure 1.6

Body Planes and Sections Oblique section through the trunk

Body Cavities and Membranes Dorsal body cavity Cavity subdivided

into the cranial cavity and the vertebral cavity. Cranial cavity

houses the brain. Vertebral cavity

runs through the vertebral column and encloses the spinal cord

Body Cavities and Membranes Ventral body cavity

– subdivided into: Thoracic cavity –

divided into three parts

Two lateral parts each containing a lung surrounded by a pleural cavity

Mediastinum – contains the heart surrounded by the pericardial sac

Body Cavities and Membranes Ventral body cavity

Abdominopelvic cavity – divided into two parts

Abdominal cavity – contains the liver, stomach, kidneys, and other organs

Pelvic cavity – contains the bladder, some reproductive organs, and rectum

Body Cavities and Membranes Serous cavities – a slit-like space lined by a

serous membrane Pleura, pericardium, and peritoneum

Parietal serosa – outer wall of the cavity Visceral serosa covers the visceral organs

Body Cavities and Membranes

Other Body Cavities Oral cavity Nasal cavity Orbital cavities Middle ear cavities Synovial cavities

Abdominal Regions and Quadrants Abdominal regions divide the abdomen into

nine regions

Abdominal Quadrants Abdominal quadrants divide the abdomen into four

quadrants Right upper and left upper quadrants Right lower and left lower quadrants

FOUR TYPES OF FOUR TYPES OF ANIMAL TISSUESANIMAL TISSUES

EPITHELIAL TISSUEEPITHELIAL TISSUE(COVERING)(COVERING)

Tightly-joined closely-packed cells One side of epithelium exposed to air

or internal fluid, other side attached to a basement membrane, a dense mat of extracellular matrix (connective tissue)

Covers the outside of the body and lines the internal organs and cavities

Barrier against mechanical injury, invasive microorganisms, and fluid loss

Provides surface for absorption, excretion and transport of molecules

TYPES OF TYPES OF EPITHELIAL EPITHELIAL TISSUETISSUE Cell shape

Squamous (flat & thin) Cuboidal (box or square) Columnar (rectangular)

Number of cell layers Simple (one) Stratified (two or more) Pseudostratified (one but

appears to be two) RELATE STRUCTURE TO

FUNCTION!

CONNECTIVE TISSUE(FRAMEWORK) Main function: binding

and support other tissues

Large amount of extra-cellular matrix with fewer cells

Connective tissue cells secrete the extra-cellular matrix

Extracellular matrix consists of network of fibers in liquid, jelly-like or solid matrix

MUSCLE TISSUEMUSCLE TISSUE(MOVEMENT)(MOVEMENT) Composed of long cells

called muscle fibers Contraction movement

NERVOUS TISSUENERVOUS TISSUE(CONTROL)(CONTROL)

Senses stimuli and transmits signals called nerve impulses from one part of an animal to another

Consists of a cell body and long extensions called dendrites (towards cell body) and axons (towards another cell or an effector)

Axon

Dendrite

Cell body

Tissue Type Epithelial Connective Muscle Nerve

Cell Shape Flattened, cuboidal, columnar

Irregular or round Elongated Cell appendages branched

Cell Arrangement

Single multilayered

Scattered in matrix

In sheets or bundles

Isolated or networked

Location Body covering or lining organs or

cavities

Supports other organs

Lining internal organs, make

skeletal muscles

Concentrated in brain and spinal cord + all over

the body

Surface Feature of Cells

Cilia, microvilli - - -

Matrix Type Basement membrane

Varied – protein fibers + liquid, gelatinous, firm

to calcified

- -

Matrix Amount Minimal Extensive Absent Absent

Unique Feature No direct blood supply, except for

glands

Cartilage has no blood supply

Can generate electrical signals,

force and movement

Can generate electrical signal