COMPARING HUMAN RESPIRATORY STRUCTURES TO THOSE OF OTHER VERTEBRATES

In humans, a bony palate separates the nasal cavity from the oral cavity and this insures that humans can continue breathing even while eating. Nasal conchae cause turbulence in air to warm and humidify the air and causes microbes and debris to get caught in mucus lining the nasal cavity. Air then passes through the pharynx (nasopharynx, oropharynx, and laringopharynx) before passing through the larynx. Vocal cords are located in the larynx as is the epiglottis which closes over the opening to the larynx as we swallow.

Human models

human palatehuman

Lungfish and turtle

lungfishturtle

cat

catcat

sheep and turtle

sheepmonkey

Air passes from the larynx into the trachea which divides into bronchi.

Turtle

turtle

alligator

sheep and cat

sheepcat

monkey

monkeymonkey

monkeymonkey

GILLS

Fish possess internal gills where they exchange oxygen between the water and their blood. Lungfish possess both lungs and gills (the gills of lungfish are depicted below; the lungs are depicted in the next page on lungs).

lungfish

Even though amniotes do not possess lungs, their embryos develop the pharyngeal arches (with branches of the aortic arches, cartilaginous bars, clefts between them, etc.) comparable to the pharyngeal arches in fish embryos which will develop into gills.

pig embryo

pig

WHAT SPECIFIC SIMILARITIES AND DIFFERENCES DID YOU NOTICE BETWEEN THE HUMAN STRUCTURES AND THOSE OF OTHER VERTEBRATES? HOW DO THESE STRUCTURAL SIMILARITIES/DIFFERENCES COMPARE TO SIMILARITIES/DIFFERENCES IN LIFESTYLE? WHAT MAKES HUMANS UNIQUE? WHAT RELATIONSHIPS BETWEEN ORGANISMS DO YOU FEEL ARE SUPPORTED BY YOUR COMPARISONS OF THEIR FEATURES? WHAT FEATURES DO YOU FEEL DEFINE A PARTICULAR GROUP?
LUNGS