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pogonyaev
3 years ago
7

REALLY NEED HELP

Biology
1 answer:
Liono4ka [1.6K]3 years ago
4 0
T cell activation is initiated by an activated B cell.

The B cell presents antigens on its MHC receptors. The T cell recognizes the antigen bound to the MHC. There are other cosignals that fully activate the at cells but the antigen on the MHC receptor on the B cell is where it all starts.
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Which process releases energy instead of using energy?
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The correct answer is option (D) A sandwich is digested and converted to carbon dioxide and water.

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3 years ago
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What processes are needed for sedimentary rock to become igneous rock?
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A sedimentary rock can become an igneous rock by melting and solidification.

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2 years ago
Which three of the following entities are acellular?.
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Answer:

Prions archea, viroids bacteria, viruses protists are acellular while fungi is cellular.

While viruses have indeed been closely researched for more than a century for infections of people and animals, most viruses, particularly those that infect microorganisms, are still poorly understood. 

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brainly.com/question/28475730cellular

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7 0
1 year ago
Please help<br> Explain how independent and dependent variables apply to life
Crazy boy [7]

Answer:

If one wants to estimate the cost of living of an individual, then the factors such as salary, age, marital status, etc. are independent variables, while the cost of living of a person is highly dependent on such factors. Therefore, they are designated as the dependent variable.

4 0
2 years ago
The ribosome of the bacterium E. coli includes the ribosomal protein L4 (rpl4). The rpl4 gene carries the instructions for makin
Mandarinka [93]

Answer:

Every organism possesses in its ribosome a protein that is similar to rpl4. This protein has an amino acid sequence that is similar to the sequence of E. coli’s rpl4.

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Phylogenetic tree is a diagram which represents the similarities between different organisms and shows their evolutionary histories.

The presence of a similar genetic sequence or amino acid sequence shows that the gene is common in all those organisms. This means that all organisms had a common ancestor through which the gene or amino acid was transferred. The genetic r amino acid sequence remained common in all the different organisms.

6 0
3 years ago
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