Answer:
Option A, They contain a thick tunica media
Explanation:
Artery consist of tunics which is made up of three distinct layers
a) The internal layer is tunica intima – made up of epithelial and connective tissue layers
b) The middle layer is tunica media - thickest layer in arteries and consists of layers of smooth muscle supported by connective tissue
c) The external layer is tunica externa - sheath of connective tissue composed primarily of collagenous fibers
Answer:
They rely on the sun's heat (True)
Explanation:
( You could also use artificial heat like heating lamps but the sun's heat is what most reptiles use)
Over time, the toxins from inhaled cigarette smoke break the thin walls of alveoli, leaving larger, less efficient air sacs. The sacs also begin to lose their bounce, making it harder to bring in the oxygen and expel carbon dioxide. 3 Both can become partially trapped in the lungs.
Answer :3. similarities among vertebrate forelimbs suggest that they evolved from a common ancestor.
Explanation:
The study of differences and similarities in the anatomy of different species is comparative anatomy. It is based on the concept that
1.)Homologous structures which are present in different species, because they have a common decent and must have evolved divergently from a shared ancestor. Theses anatomic structures may not be used for the same purposes. For example the forelimb of fox and whale.
2. Some structures (Analogous)which are similar in different organisms must have evolved ,(acquired through natural selection) through convergent evolution in similar environment, and not inherited from a recent ancestor. These organisms usually use these structures for a common purpose. For example the streamline body shape of shark and porpoises, which though are used for a common purpose of swimming, were inherited from different ancestors.
. Example of comparative anatomy is the common bone structures in forelimbs of fox, whales, bats, and humans. These appendages is made up of the same basic parts; despite serving different functions.
Comparative anatomy helps scientists in classification of organisms based on their similar characteristics of their anatomical structures.