A tetrad consists of 2 homologous chromosomes each of which is made up of 2 sister chromatids
Answer:
There are from 200-500 million alveoli (mean diameter = 200 micrometers) in adult human lungs
Explanation:
The epithelial cells of the alveolar septum are markedly thinned and the capillary network immediately beneath the epithelium is the richest in the body.hope this helps you :)
Answer:
The grasshopper doesn't have to use it circulatory system to carry gases to and from the grasshopper cells because the air that is passed through the trachea system is already close enough to get to the cells.
Explanation:
"In the grasshopper, exchange of oxygen and carbon dioxide occurs in the tracheal system. Hemolymph plays no part in the process. There is not even an oxygen-carrying pigment in insect hemolymph." - www.biology-pages.info
(Here's some extra info as well)