Embryonic Story - Patterns of the Body Wall and Body Cavity

what is the trunk?

the span of the vertebral column

What is the body wall antomy of the embryo?

Notochord: signals cells, helps embryonic developement

neural tube- runs from head to tail and becomes spinal cord and brain, skeletal and preganglionic motor neurons cell bodies in spinal cord so also develop here

neural crest- becomes posterior root & root ganglion, psuedounipolar neurons

Vessels: post gangionic nervs

what are somites? what are the different types?

they are blocks of embyonic tissue

dermatome- skin

sclerotome- bone

myotome: epimere: dorsal muscle, hypomere: verntral muscle

what does dermatome become?

dermis

what does sclerotome become?

the bones of the vertebral column and ribs

What does the myotome become?

skeletal muscle

what are the two different types of myotome and how are they different?

epimere - becomes epaxial muscles, dorsal muscles

hypomere- becomes hypaxial muscles, ventral muscls

what are the epaxial muscles?

superficial and deep musculature

what are the hypaxial muscles?

ventral musculature

lateral musculature

sub vertebral musculature

what are the r general layers for the lateral musculature?

outermost muscles

external muscles

middle muscles

internal muscles

how does the spinal nerve design accommodate for the different muscles of the body wall?

anterior ramus innervates hypaxial muscles

posterior ramus innervates epaxial muscles

between what layers of muscles do nerves, veins, and arteries run between?

internal and middle

what is the vascular & nervous pattern?

Vein

Artery

Nerve

what is a body cavity?

the space within the bone and muscle

what is a coelom?

• mesothelium sack that contains serous fluid to reduce friction

• lining body cavities

what are the different parts of the coelom?

parietal membrane - part against body wall

visceral membrane - part against organ

mesenteric membrane - connecting visceral and parietal

mesentery - space in between mesenteric membrane containing vessels and nerves

coelomic cavity - part actually inside coelom with serous fluid