The ends of the dna chains are made up of several repeating nucleotides that do not function in genetic instruction or as genes. These end nucleotides are called A. Telomeres

B. Histones

C. Chromatids

D. Centromeres

Drag each tile to the correct box. the body monitors the levels of oxygen in the blood to regulate breathing. isabel is running in a marathon and is near the finish line. she feels out of breath. how will her nervous system work to generate a reaction? arrange the tiles in chronological order. isabel's breathing rate increases. sensory receptors in the arteries detect low oxygen levels. the brain sends signals through motor neurons. sensory neurons generate an impulse. the central nervous system relays an impulse to certain brain regions.

Explain how paleontologists use trilobite fossils as index fossils for various geologic time periods.

If an organ has six haploid chromosomes, how many chromosomes are present. 6 12