For Each of the Elements Below, There Are Only Two

question 89

Multiple Choice

For each of the elements below, there are only two naturally occurring isotopes. Using information in your periodic table, identify the pair in which the heavier isotope is the more abundant one.

• A)(⁶³Cu and ⁶⁵Cu)
• B)(⁸⁵Rb and ⁸⁷Rb)
• C)(¹⁰B and ¹¹B)
• D)(⁷⁹Br and ⁸¹Br)
• E)(¹⁴N and ¹⁵N)

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Definitions:

Cytokines

Small proteins released by cells that have a specific effect on the interactions and communications between cells, often playing a pivotal role in immune responses.

Memory B Cell

A Memory B Cell is a type of immune cell that remembers past infections, enabling the immune system to respond more quickly to repeated exposures.

Organ Rejection

The process by which a transplant recipient's immune system attacks the transplanted organ or tissue, considering it as foreign.

Cell-Mediated Immunity

An immune response that does not involve antibodies but involves the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen.