Animal fossils usually provide very little opportunity to study the actual animal tissues, because in fossils the animals' living tissues have been largely replaced by minerals. Thus, scientists were very excited recently when it appeared that a 70-million-year-old fossil of Tyrannosaurus rex (T. rex), a dinosaur, might still contain remains of the actual tissues of the animal. The discovery was made when researchers deliberately broke open the T. rex’s leg bone, thereby exposing its insides to reveal materials that seem to be remains of blood vessels, red blood cells, and collagen matrix.
First, the breaking of the fossilized leg bone revealed many small branching channels inside, which probably correspond to hollows in the bones where blood vessels were once located. The exciting finding was the presence of a soft, flexible organic substance inside the channels. This soft substance may very well represent the remains of the actual blood vessels of T. rex.
Second, microscopic examination of the various parts of the inner bone revealed the presence of spheres that could be the remains of red blood cells. Tests showed that the spheres contained iron-a material vital to the role of red blood cells in transporting oxygen to tissues. Moreover, the spheres had dark red centers (substances with iron tend to be reddish in color) and were also about the size of red blood cells.
Third, scientists performed a test on the dinosaur leg bone that showed that it contained collagen. Collagen is a fibrous protein that is a main component of living bone tissue, in which it forms a so-called collagen matrix. Collagen (or its chemical derivatives) is exactly the kind of biochemical material that one would expect to find in association with bone tissue.
The reading and listening materials have a debate on the authenticity of t.rex tissues found by scientists. Some scientists claim it is the first dinosaur tissue ever found. The author provides three reasons to support this claim but the following speaker holds an opposite view.
First, the author mentions the presence of soft organic substance inside channels found on bones. According to the author, these soft substances may very well represent the remains of the actual blood vessels of t .rex.
However, the speaker opposes this by saying that sometimes when bacteria colonize inside the bone, They create hollows and some chemical leftovers that look very similar to what scientists found.
Second, the author argues that there are presences of spheres inside the inner bone that could be the remains of red blood cells. these spheres contained irons which are necessary for normal functioning of blood cells. However, the speaker explains that the same evidence found on primitive animals in the exact same site . As we know Primitive animals have no blood cells, therefore, this argument is not valid.
Lastly, the author points out that performed tests on the dinosaur leg showed that it contained collagen and collagen expected to be found on bone tissues. The speaker explains that oldest tissues ever found were 1,000 years old and as result scientists believe no tissues can last longer.
But the fossil found on the site appears to be 70 million years old. There is an enormous gap between these numbers that could not be explained.
| Post date | Users | Rates | Link to Content |
|---|---|---|---|
| 2018-11-28 | Mohammed AlKhars | 3 | view |
| 2018-11-28 | Mohammed AlKhars | 3 | view |
| 2018-11-28 | Mohammed AlKhars | 3 | view |
| 2018-10-19 | prem123 | 76 | view |
| 2018-10-18 | Munaim Hossain | 90 | view |
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Grammar and spelling errors:
Line 1, column 73, Rule ID: WHITESPACE_RULE
Message: Possible typo: you repeated a whitespace
Suggestion:
...als have a debate on the authenticity of t.rex tissues found by scientists. Some ...
^^
Line 3, column 214, Rule ID: COMMA_PARENTHESIS_WHITESPACE
Message: Don't put a space before the full stop
Suggestion: .
...remains of the actual blood vessels of t .rex. However, the speaker opposes this ...
^^
Line 6, column 131, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: These
...ould be the remains of red blood cells. these spheres contained irons which are neces...
^^^^^
Line 6, column 322, Rule ID: COMMA_PARENTHESIS_WHITESPACE
Message: Don't put a space before the full stop
Suggestion: .
...primitive animals in the exact same site . As we know Primitive animals have no bl...
^^
Transition Words or Phrases used:
but, first, however, lastly, look, may, second, so, then, therefore, well
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 10.0 10.4613686534 96% => OK
Auxiliary verbs: 4.0 5.04856512141 79% => OK
Conjunction : 6.0 7.30242825607 82% => OK
Relative clauses : 11.0 12.0772626932 91% => OK
Pronoun: 19.0 22.412803532 85% => OK
Preposition: 27.0 30.3222958057 89% => OK
Nominalization: 4.0 5.01324503311 80% => OK
Performance on vocabulary words:
No of characters: 1305.0 1373.03311258 95% => OK
No of words: 254.0 270.72406181 94% => More content wanted.
Chars per words: 5.13779527559 5.08290768461 101% => OK
Fourth root words length: 3.99216450694 4.04702891845 99% => OK
Word Length SD: 2.37406854597 2.5805825403 92% => OK
Unique words: 147.0 145.348785872 101% => OK
Unique words percentage: 0.57874015748 0.540411800872 107% => OK
syllable_count: 384.3 419.366225166 92% => OK
avg_syllables_per_word: 1.5 1.55342163355 97% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 4.0 3.25607064018 123% => OK
Article: 8.0 8.23620309051 97% => OK
Subordination: 1.0 1.25165562914 80% => OK
Conjunction: 1.0 1.51434878587 66% => OK
Preposition: 1.0 2.5761589404 39% => More preposition wanted as sentence beginning.
Performance on sentences:
How many sentences: 14.0 13.0662251656 107% => OK
Sentence length: 18.0 21.2450331126 85% => The Avg. Sentence Length is relatively short.
Sentence length SD: 34.3003688919 49.2860985944 70% => OK
Chars per sentence: 93.2142857143 110.228320801 85% => OK
Words per sentence: 18.1428571429 21.698381199 84% => OK
Discourse Markers: 5.21428571429 7.06452816374 74% => OK
Paragraphs: 6.0 4.09492273731 147% => Less paragraphs wanted.
Language errors: 4.0 4.19205298013 95% => OK
Sentences with positive sentiment : 3.0 4.33554083885 69% => OK
Sentences with negative sentiment : 3.0 4.45695364238 67% => OK
Sentences with neutral sentiment: 8.0 4.27373068433 187% => OK
What are sentences with positive/Negative/neutral sentiment?
Coherence and Cohesion:
Essay topic to essay body coherence: 0.137670999471 0.272083759551 51% => OK
Sentence topic coherence: 0.0468042325858 0.0996497079465 47% => OK
Sentence topic coherence SD: 0.0384796410071 0.0662205650399 58% => OK
Paragraph topic coherence: 0.0659261807657 0.162205337803 41% => OK
Paragraph topic coherence SD: 0.0102183862265 0.0443174109184 23% => Paragraphs are similar to each other. Some content may get duplicated or it is not exactly right on the topic.
Essay readability:
automated_readability_index: 11.8 13.3589403974 88% => Automated_readability_index is low.
flesch_reading_ease: 61.67 53.8541721854 115% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 9.1 11.0289183223 83% => OK
coleman_liau_index: 12.24 12.2367328918 100% => OK
dale_chall_readability_score: 8.57 8.42419426049 102% => OK
difficult_words: 65.0 63.6247240618 102% => OK
linsear_write_formula: 7.5 10.7273730684 70% => OK
gunning_fog: 9.2 10.498013245 88% => OK
text_standard: 9.0 11.2008830022 80% => OK
What are above readability scores?
---------------------
Maximum four paragraphs wanted.
Rates: 76.6666666667 out of 100
Scores by essay e-grader: 23.0 Out of 30
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Note: the e-grader does NOT examine the meaning of words and ideas. VIP users will receive further evaluations by advanced module of e-grader and human graders.