The circulatory system and the respiratory system work together to exchange
oxygen and carbon dioxide in the lungs.
true
false

True

Explanation:

The respiratory system get air while the circulatory system  takes that air spreads it to all of the cells

True!

Explanation:

The circulatory system helps to pump blood throughout the body. This is important because red blood cells work to carry oxygen throughout the body. The respiratory system is what allows us to breathe in this oxygen that is later absorbed by red blood cells. The respiratory system also extracts carbon dioxide from the blood which we later breathe out.

it's     c       this is a cell (b) with a nucleus (c) containing dna (a). the dna is organized into chromosomes (d). a section of the chromosome that codes for a trait is called a gene (e).

small, big, or no change could occur in the phenotype. it could cause something as simple as a cats ears to curl backwards or something as frighting as death. it could also occur in the protien-coding area and have an effect on that but no effect on the amino acids. what has to occur is a changing in the hox gene or the control gene.