- Biology Definition: Respiration is a chemical reaction that happens in all living cells. (Both plant cells and animal cells). Respiration is the way that energy is released from glucose so that all the other chemical processes needed for life can happen.
- Normal definition: The action of breathing, also called ventilation.
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A change in their food, from trees to grass in the Great Plains.
Answer:
a. hox genes.
Explanation:
HOX genes have the following functions:
- HOX genes are the homeobox subset.
- They specify the areas of the embryo's body plan along the animal head-tail axis.
- They are encoding Hox proteins that specify the position characteristics and ensure that the right structures form at the right position in the body.
- They regulate high-level executive genes, such as transcription factors and intracellular signaling molecules, which adhere, number, form, and growth to cells.
The vertebrates are highly preserved.
The clusters and other genes occur uninterrupted.
Evolutionary, the heterogeneous regulatory areas between the genes most previously present are larger and more preserved than those present at the other ends of the clusters.
The characteristical feature is that these are homeodomain proteins with a highly preserved area of DNA binding encoded with homeobox gens.
Xylem and Phloem make up Vascular Tissue.