input with options: Q: A colloid is a homogeneous mixture with medium-sized what? A:
OPTIONS:
- atoms
- solutions
- molecules
- particles
output: particles

Q: Q: During the first several weeks of development, the cells of the endometrium nourish what? A:

OPTIONS:
- egg
- nucleus
- uterus
- embryo

A: embryo

input: OPTIONS:
- organisms
- fluorescence
- ligaments
- organelle Now, answer this question: Q: What term is used to describe muscle fibers that allows muscles to contract? A:
A:
output: organelle

Q: Cephalization refers to the development of what anatomical region, which evolved at the same time as bilateral symmetry in animals? A:

OPTIONS:
- tail
- chest
- heart
- head

Answer: head

Problem: OPTIONS:
- lipids
- rna
- gas
- protein
Q: Q: Each endocrine hormone affects only certain "target" cells, which have molecules of what on the surface that enable binding of a given hormone? A:
Answer: protein

Q: What is the term for the gases that surround a planet? A:

OPTIONS:
- hemisphere
- galaxy
- biosphere
- the atmosphere

Answer:
the atmosphere