BIOLOGY 1A03 Chapter Notes - Chapter 3: Histone Acetyltransferase, Embryonic Stem Cell, Blastomere

• School: McMaster University
• Department: Biology
• Course: BIOLOGY 1A03
• Professor: Rosa Da Silva

Document Summary

Cells in multicellular organisms must differentiate their structure and function by regulating gene expression. Eukaryotic dna is organized into chromatin to maintain a transcriptionally inactive state. All cells in the body are derived from a single fertilized egg. At some point, as a zygote, all embryonic stem cells are identical. Early embryonic stem cells have have an almost unlimited ability to mature and differentiate into the many different cell types in the body. The fate of an embryonic cell depends on the signals that are exchanged and which genes are switched on or off at speci c times. Red blood cells: shape and size maximizes surface area for gas exchange. Hepatocytes (liver cells): contain large amounts of rough er needed for protein synthesis. Muscle cells: long, multinucleate, and packed with actin and myosin needed for contraction. Intestinal epithelial cells: microvilli increase their absorptive surface area. Neurons: long extensions of the plasma membrane allow neurons to communicate.