Comparative Vertebrate Anatomy - Exam 1 Review

Phlyum Chordata

Made up of a group of animals all possessing four common features.

What are the four features?

• Notochord

• Dorsal Hollow Nerve Cord

• Postanal Tail

• Endostyle

Notochord

A rigid cartilaginous rod defining the longitudinal axis in the embryo.

Dorsal Hollow Nerve Cord

The spinal cord and brain.

Postanal Tail

Posterior to the anus

Endostyle

A glandular groove in the floor of the pharynx

Urochordata

Sea squirts and turnicates.

Cephalochordata

Amphioxus

Vertebrata/Craniata

Chordates having a vertebral column of bone or cartilage.

What are the three main body regions?

• Head

• Trunk

• Tail

Cranialization

The development of the head

Coelom

A body cavity that houses the visceral organs.

Neck

A narrow structure connecting the head to the trunk.

Bilateral Symmetry

The vertebrate body can be divided into two equal right and left hand portions.

Transverse Plane

Separates cranial and caudal structures along the trunk (ex; transverse processes of vertebrae) and proximal from distal structures on the limb in most vertebrates.

Sagittal Plane

A vertical plane dividing the body into left and right portions.

Midsagittal

Runs along the midline of the body

Parasagittal

Runs along other than the midline of the body.

Dorsal Plane

Divides the body into ventral and dorsal portions.

Metamerism (or Segmentation)

Serial repetition of structures along the long axis of the body.

Centrum

The weight bearing portion of the vertebrate

Neurolation

Occurs along the longitudinal axis of the embryo dorsal to the notochord.

Neurocoel

The hollow center of the vertebrate nerve cord.

Neural Groove

Forms dorsal to the notochord.

The neural groove will sink into the embryonic body and

close off to form the what?

Neural Groove

Neural Keel

A wedge shaped ectodermal structure dorsal to the notochord.

Pharynx

Shows the relationship between vertebrates and other chordates.

Ectodermal Grooves

Grooves in the abovelyng ectoderm

If the branchial plate ruptures, a passageway forms called what?

Pharyngeal Slit

Eustachian Tube

The pharyngeal pouch that doesn’t seal back up in mammals.

Between adjacent pharyngeal pouches/slits are columns of tissue

called what?

Pharyngeal Arches

Mandibular Arch

First pharyngeal arches that house the upper and lower jaw.

Hyoid Arch

The second pharyngeal arch.

Branchial/Gill Arches

The remaining arches 1-5.

Outer Tube

Body wall

Inner Tube

Digestive tract.

Coelem

The space between the outer and inner tubes.

Pericardial Activity

Houses the heart.

Pleuroperitoneal Cavity

Houses the rest of the viscera.

What are the four classes of tissues?

• Epithleal

• Connective

• Muscle

• Nervous

Epitthleal Tisssues

Cover the body and lines the body cavities; covering all inner and outer body surfaces.

Epithelium

Composed mostly of epithelial cells in very close contact with one another.

Epithelial Tissue Classification

• Cell shape

• Number of cell layers

Squamous Cells

Are low, flattened cells. They are scale-like in appearance.

Cubodial Cells

Are cube shaped cells (in 2D), of an equal height and width.

Columnar Cells

Are column shaped cells (in 2D). They are taller than they are wide.

Simple

One layer of cells.

Stratified

More than one layer of cells.

Pseudostratifed

Composed of one layer of cells of uneven height.

Simple squamous

One layer of flattened cells

Mesothelium

Epithelium lining the ventral body cavities and their associated organs.

Endothelium

Epithelium lining all the hollow organs of the circulatory system.

Simple Cuboidal

Single layer of cube-shaped cells.

Simple Columnar

Single layer of columnar-shaped cells.

Pseudostratified Columnar

A single layer of columnar-shaped cells of varying height giving the false impression of being more than one thickness.

Stratified Squamous

More than one layer of flattened cells.

Stratified Squamous Keratinized

Forms the epidermis of amniotic skin

Stratified Squamous Nonkeratinized (Mucus Type)

Forms the epidermis of aquatic amphibians.

Stratified Cuboidal

More than one layer of cubodial-shaped cells.

Stratified Columnar

More than one layer of columnar-shaped cells.

Transitional

A stratified epithelium made up of variably shaped cells (ex; lining the urinary bladder)

Glands

Are structures composed of epithelial cells which secrete an aqueous fluid product.

Classification of Glands

• Number of cells

• Mode of secretion

Unicellular

Made up of one cell.

Muiltcellular

Made up of more than one cell.

Exocrine Glands

Secretes their products through their ducts.

Endocrine Glands

Secretes their products into the blood stream.

Connective Tissue (C.T.)

All arise from mesoderm.

All c.t. are derived from an embryonic tissue

called what?

Mesenchyme

Extracellular Matrix

C.T. cells are seperated.

Connective Tissues Proper

This is a diverse group (divided further into the two subclasses of loose and dense c.t.s)

Areolar Connective Tissue

It underlies most of the body’s epithelia and surrounds small nerves and blood vessels.

Collagen Fibers

The strongest and most abundant class, the least flexible.

Recticular Fibers

Branching fibers which can also withstand tension,

Elastic Fibers

The weakest but most flexible of the three fiber types, most flexible.

Fibroblasts

Are immature c.t. cells which produce the fibers of areolar c.t.

Reticular Connective Tissue

Much like areolar c.t. except that it has only one fiber type, the reticular fiber.

Adipose Tissue

Store nutrients, insulate the body, and protect the body from trauma.

Adipocytes

The cells of adipose tissue.

Dense Connective Tissue

Have a much higher fiber content and a resulting lower cellular content than does loose c.t. It is a stronger, more resilient tissue than is loose c.t.

Dense Irregular Connective Tissue

Has its fibers (primarily collagen) running in a random or irregular pattern.

Dense Regular Connective Tissue

Has its fibers arranged into a regular repeating pattern.

Elastic Connective Tissue

A dense regular c.t. where the fiber type is the elastic fiber.

Blood

The extracellular matrix is very fluid and termed “plasma”.

Cartilage

A firm but resilient c.t.

Lacunae

Fluid-filled cavities in the matrix

Chondrocyte

Main cell of cartilage.

Bone

The densest of the c.t.

Osteocyte

The Main cell type in bone.

Muscle Tissue

Allows for the movement of the body and of structures

within the body.

Skeletal Tissue

Striated, multinuceated, voluntary, associated with the

skeleton.

Cardiac Tissue

Striated, 1 -2 nuclei, involuntary, branching cells, found

only in the heart

Smooth Tissue

Nonstriated, uninucleated, involuntary, associated

with the hollow organs (ex; stomach) and glands.

Nervous Tissue

Regulates and controls bodily functions.

Neurons

Antomical term for the nerve cells.

Supporting Cells

A variety of cells that help assist.

Epidermis

The superficial most layer of the skin/integument. It is a multilayered epithelium derived from ectoderm.

Dermis

The deepest layer of the skin and the middle layer of the

integument.

Hypodermis

The deepest layer of the integument.

Goblet Cells

Produce mucus.