Biolog 15 - Chapter 15: Control over Genes I. Gene Control...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 15: Control over Genes I. Gene Control A. Negative Control Systems: system in which a regulatory protein can bind to DNA at a certain site and block transcription B. Positive Control Systems: system in which a regulatory protein binds to the DNA and promotes the initiation of transcription C. Cells exert control over when, how, and to what extent each of their genes is expressed D. The expression of a given gene depends on the type of cell and its functions, on chemical conditions, and on signals from the outside environment E. Regulatory proteins and other molecules govern gene expression through interactions with DNA, RNA, and gene products (polypeptide chains, and then proteins) F. Cell Differentiation: when embryonic cells and their descendants activate and suppress a few of the total number of genes in unique, selective ways II. Gene Control Outcomes A. X-chromosome inactivation occurs when the x chromosome is inactivated when XX embryos are in a ball of cells. B. XIST is a product of methlyation of histones that sticks to chromosomal DNA
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/03/2011 for the course CHEM BIO P 101 taught by Professor Kk during the Spring '11 term at Rochester.

Page1 / 2

Biolog 15 - Chapter 15: Control over Genes I. Gene Control...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online