Q: What is the smallest particle of an element that still has the element's properties? Choices: - an ion - a nucleus - an electron - an atom A:
an atom

Q: What structure connects the fetus to the placenta, allowing the exchange of gases? Choices: - sediment cord - skin cord - belly button - umbilical cord A:
umbilical cord

Q: Q: The organ systems of the body work together to carry out life processes and maintain what? Choices: - movement - freshness - consciousness - homeostasis A:
A: homeostasis

Question: Q: All three axes are established before the zygote begins to undergo what? Choices: - cloning - birth - twinning - cleavage A:
Answer: cleavage

*Question*
Q: Designed to exchange materials, what spongy structure consists of membranes and blood vessels from both mother and embryo? Choices: - endometrium - uterus - umbilicus - placenta A:
**Answer**
placenta

Q: Burning trees produces most of the same pollutants as burning what? Choices: - fossil compounds - carbon - coal fuels - fossil fuels A:
fossil fuels