1. Each duckling came from these parents. They look similar, but they are not exactly the same. Why are they not identical? Explain. 2. Identify and describe something that has a particular structure.
3. Your facial features are visible cues to others. They help you express, or show, your emotions. How does this relate to the way genes are expressed?
4. What would happen to offspring if crossing over did not occur?

prophase: we can observe the chromosomes to coil up and condense. they become visible. nuclear membrane and envelope disintigrate.s

metaphase: chromosomes align at the center, the metaphase plate. spindle fibers attach to centromeres of the sister chromatids. they meet at kinetochores.

anaphase: sister chromatids are pulled towards each opposing centromere, set on different poles.

telophase: chromosomes are now clustered up only on either sides of the cell. nuclear membranes reform, and a new cell wall forms along the cell plate. this will lead to cytokinesis, the process that divides the cell membrane and forms the cell wall.

oxygen = 21% of the atmosphere

nitrogen = 78%

carbon dioxide = 0.1%

argon =0.934%