TPO 24

Both passages refer to whether the evidence found by cracking open a 70 million year old leg bone fossil of T-Rex can be considered as remains of actual tissue or not. The passage supports its validity, whereas the listening contradicts the reading's arguments.

First of all, according to the lecturer, the article's opinion that the branching channels found in the fossil represent the location of blood vessels, is incorrect. More specifically, the aural passage cites that there is a high possibility that the soft substance could be the residue of bacteria colonization, which occurred afterwards, because bacteria leave traces of soft residue.

Secondly, the passage supports that the existence of spheres found inside the bone containing iron, could be remains of red blood cells. However, the lecturer explains that the exact same spheres have been found in animals who had not any red blood cells. Therefore, those spheres are more likely reddish minerals.

Finally, the reading states that various tests that have been conducted in the fossil indicated the existence of collagen that is closely related with bone tissue. Conversely, the listening mentions that no one ever found collagen in fossils older than 1 thousand years, hence, the source of the collagen is not T-Rex, but something else like human skin from the researchers.