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Alenkinab [10]
3 years ago
8

7. When did whale ancestors begin living full time in the water?

Biology
1 answer:
antoniya [11.8K]3 years ago
8 0
Around 40 million years ago

The earliest whales that we think were fully aquatic, that is, they never left the water, are found around 40 million years ago, during the middle Eocene. That means that the transition from terrestrial animals to fully aquatic animals took about 12 million years.
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does the presence of introns exons in eukaroytic cells provide more potentia diversity in gene products than is possible in pork
Leona [35]

Answer: Yes. Splicing can be done in different ways to yield different mRNAs wich will create different proteins. Prokaryotes are not able to do this.

Explanation:

DNA (deoxyribonucleic acid) is a molecule that contains the genetic information for synthesizing amino acids that form proteins. To do this, DNA must first be transcribed into RNA (ribonucleic acid) and this is the molecule used for protein synthesis (translation). The newly transcribed RNA (called primary messenger RNA) from DNA results in a very long molecule and also has regions that do not code for anything, called introns, which are removed by a process called splicing. Exons are segments in the RNA that do code for amino acids and remain in the mature mRNA after splicing.

<u>Splicing is a process by which introns are cleaved from the primary messenger RNA and exons are joined to generate mature messenger RNA.</u> In addition, alternative splicing occurs which allows different mRNA isoforms and thus different proteins to be obtained from a primary mRNA transcript. This is because the exons will be joined or spliced in different ways, giving rise to different mature messenger RNA sequences. This process occurs mainly in eukaryotes, although it can also be observed in viruses. But it does not take place in Prokaryotes (Bacteria).

In summary, exons/introns can be spliced together in different ways to yield different mRNAs sequences. Each different mRNA sequence will code for a different protein.

6 0
2 years ago
I need too know the answer
Dmitrij [34]
 answer is polygenic inheritance
5 0
2 years ago
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. You have constructed four different libraries: a genomic library made fromDNA isolated from human brain tissue, a genomic libr
aksik [14]

Answer:

A) Brain genomic library and muscle genomic library.

B) Brain genomic library and muscle genomic library - overlap completely.

Human brain cDNA library, and a human muscle cDNA library and other library is partially overlap.

Explanation:

A) The genomic library contains the whole genome content of the organism whereas cDNA library contains the coding genome of the organisms. Brain genomic library and muscle genomic library will constitute the all the genomic sequences of brain and muscle.  The cDNA library is prepared from the mRNA and the coding regions are present in this library.

B) The overlapping in the genome library might occur due to the common sequences present in the genome. Brain genomic library and muscle genomic library might completely overlap with each other as they have more sequence common among each other. All the other library may be partially overlap with each other as they have some common DNA sequences and neither library can have unique sequences.

7 0
3 years ago
The primary goal of modern systematics is construct 'family trees' that exhibit _________________ relationships Question 5 optio
Neko [114]

Answer:

Polyphyletic relationships .

Explanation:

The primary goal of modern systematics is construct 'family trees' that exhibit polyphyletic relationships because systemics deals with grouping or organising living organisms into groups base on biological meanings of function and polyphyletic relationships which is organising or grouping of organisms that don't have common ancestors Into different groups or unrelated organisms.

3 0
3 years ago
Most rocks are made of_________ minerals
nasty-shy [4]

Answer:

Scientists can distinguish more than 4,000 different minerals but many are very rare. About 200 minerals make up the bulk of most rocks. The feldspar mineral family is the most abundant. Quartz, calcite, and clay minerals are also common.

Explanation:

Here's what i found hope it helps

7 0
2 years ago
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