Kangaroos are mammals that lack a placenta. Therefore, they must have an alternate way of supplying the developing embryo with

Kangaroos are mammals that lack a placenta. Therefore, they must have an alternate way of supplying the developing embryo with nutrients.

Explanation:

The placenta provides the growing fetus with the nutrients it needs to survive in the womb.

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it enhances antibody production by t cells of the adaptive immune system.

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explanation:

scientists have discovered that hiv does not cause aids by the virus's direct effect on the host's immune cells, but rather through the cells' lethal influence on one another. researchers from the gladstone institutes have revealed that hiv does not cause aids by the virus's