Which process normally occurs at the placenta? (1) Oxygen diffuses from fetal blood to maternal
blood.
(2) Materials are exchanged between fetal and
maternal blood.
(3) Maternal blood is converted into fetal blood.
(4) Digestive enzymes pass from maternal blood
to fetal blood.

1 one

Explanation:

Which process normally occurs at the placenta? (1) Oxygen diffuses from fetal blood to maternal blood. (2) Materials are exchanged between fetal and maternal blood. (3) Maternal blood is converted into fetal blood.

Answer is option 1 oxygen diffuses from fetal blood to maternal blood

a. by using fur or clothes to trap heat energy near the body

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