BIO-1 Lecture Notes - Lecture 5: Interphase, Nuclear Membrane, Intron
Document Summary
The nucleus transcription factors to have access to them. Chromatin genes (transcription units) must be decondensed (euchromatic) in order for. Transcription requires that many different proteins be able to interact with the dna. If dna is highly compacted, transcription cannot occur. Active euchromatin has a looser structure than heterochromatin. Nuclear lamina fibrous layer beneath the nuclear envelope that supports the nuclear. Nucleolus no membrane around nucleolus, it is a specialized chromosomal region. Rrna is transcribed and ribosomal subunits are assembled in human genome, 5 pairs of chromosomes contain rdna regions, called nucleolus organizer regions, that come together to form nucleolus. Ribosomal proteins made in cytoplasm and transported to nucleolus. Ribosomal subunits come together during translation in the cytoplasm envelope, role is skeletal, lamina binds to interphase chromatin. Transport system is required to transport proteins made in the cytoplasm to the nucleus. Specific targeting signals are encoded in the amino acid sequence of proteins.
