90 mammal species become extinct in the period 1901-2000 than became extinct in the period 1801-1900.
Extinction is a situation in which something no longer exists. Their can be many reasons associated like species have been hunted to the point of extinction, scarcity of food or natural disasters.
Their are two main types of extinction firstly Mass extinction that has occurred only five times in history. The other is Background extinctions which occurs over longer period of time and are considered important in natural extinction rate.
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All chordates. a notochord is present at some point in all chordates but sometimes is lost or becomes another structure, like vertebrae
Also idk what “Tregon” so hopefully that didn’t stray from my answer being right
I'm pretty sure its c or d
Answer: codon AUG
Explanation: The codon AUG is called the START codon as it the first codon in the transcribed mRNA that undergoes translation. AUG is the most common START codon and it codes for the amino acid methionine (Met) in eukaryotes and formyl methionine (fMet) in prokaryotes.