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Thepotemich [5.8K]
3 years ago
5

The crocodile species is believed to have been around for how long? 2 million years or 200 million years?

Biology
2 answers:
Trava [24]3 years ago
5 0
Depending on your religion this answer could be 6,000 years or 200 million years but good question.
Lerok [7]3 years ago
4 0
It is 200 million years because it has been around for a long time.
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__________identify antigens and then multiply and trigger the production of other kinds of immune cells.
solong [7]

<u>Helper t-cells</u> identify antigens and then multiply and trigger the production of other kinds of immune cells.

<h3>What are helper T-cells?</h3>

Helper T-cells are one of the main types of immune cells. They detect infections and activate other immune cells to fight the infection.

Your thymus develops helper T-cells. The thymus is a small gland in the front of your chest. The other types of T-cells include:

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<h3>What are the subtypes of helper T-cells?</h3>

When helper T-cells detect an infection, they form into one of two subtypes:

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Learn more about helper T-cells

brainly.com/question/14902979

#SPJ4

5 0
2 years ago
How to gain teens trust for medical reasons?
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Which cells activate helper T-cells by antigen presentation?
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 After that the B-cells produce antibodies that are specific to the antigens of the pathogens that slow them down so the macrophages can engulf them.

6 0
4 years ago
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