Sunday, August 11, 2013

What are the structures that are formed from the four embryonic arches during human development in Your Inner Fish?Chapter 5 - Getting Ahead

In Neil Shubin's book, Your Inner Fish: A
Journey into the 3.5 Billion Year History of the Human Body,
he asserts that
embryology demonstrates that every head on every animal from a human to a shark shares
four developmental arches. These arches are best described as swellings or indentations
loaded with genes that turn on and off and instruct cells to design a head. In fish
these arches develop into gills. In humans, the first arch
forms the jaws, two small ear bones,the malleus and incus, and all the
blood vessels and muscles that run to them. The second arch
forms another ear bone, the stapes, a small throat bone, and many muscles
that are responsible for facial movement and expressions. The third arch
forms muscles, nerves, and bones used for swallowing. The
fourth arch forms the larynx and related parts. Pretty
amazing research!

No comments:

Post a Comment

What is the meaning of the 4th stanza of Eliot's Preludes, especially the lines "I am moved by fancies...Infinitely suffering thing".

A century old this year, T.S. Eliot's Preludes raises the curtain on his great modernist masterpieces, The Love...