Youtor
>> YOUR LINK HERE: ___ http://youtube.com/watch?v=lBAC863UiDY
Composition of chromosome | Class 12 Biology • About This Video ........................ • In This Video Lecture You Will Learn Basic Concept Of Composition Of Chromosomes • Chromosomes are composed of DNA and protein. Most are about 40% DNA and 60% • proteins, which have an overall negative charge, histones are positively charged due • The remainder of the chromosome called euchromatin is condensed only during cell • of 46 chromosomes. In the cell, however, the DNA is coiled allowing it to it into a much • these are the sites of RNA synthesis. The DNA of a chromosome is one very long, double • coiling occurs when the string of nucleosomes wraps up into higher order coils called • How can this long DNA ibre coil so tightly? If we gently disrupt a eukaryotic nucleus • Fitting such a strand into a small space of nucleus is nature’s marvel - and that’s only 1 • printed books of 1000 pages each, if each nucleotide corresponds to a word and each • to an abundance of the basic amino acids arginine and lysine. They are thus strongly • and examine the DNA with an electron microscope, we find that it resembles a string • its DNA. The amount of information, one chromosome contains would ill about 280 • supercoils. • smaller space than would otherwise be possible. • chromosome were laid out in a straight line, it would be about 5 centimeter long. • Highly condensed portions of the chromatin are called heterochromatin. Some of • thus act as magnetic forms that promote and guide the coiling of the DNA. Further • attracted to the negatively charged phosphate groups of the DNA. The histone cores • of eight histone proteins forming a complex known as a nucleosome. Unlike most • of beads (Fig 20.5). Every 200 nucleotides, the DNA duplex is coiled around a core • page had about 500 words on it. Further more, if the strand of DNA from a single • A typical human chromosome contains about 140 million (1.4 x 108) nucleotides in • protein. A signiicant amount of RNA is also associated with chromosomes, because • stranded iber that extends unbroken through the entire length of the chromosome. • these portions remain permanently condensed, so that their DNA is never expressed. • division, • • About This Channel..................... • I make these videos cause I love to draw and connect the complexity of science and medicine into art. I'm not saying. I'm 100% correct in all my videos, but I do try to obtain the information from credible sources. • One-stop destination for all biology lectures. • _ students in class 11, 12 or appearing for competitive medical exams ( NMDCAT ) will find it very beneficial • _ The videos are categories under various heading to make the students life simplified • Visit My Other Channel Playlist ..................... • NMDCAT PART 1: • New 1st Year Biology • NMDCAT PART 2: • New 2nd Year Biology • Class 11th Lectures: • New 1st Year Biology • Class 12th Lectures: • New 2nd Year Biology • Class 10th Lectures: • • Matric Biology • Subscribe My Channel: • / aliacademya7r • Social Link........................ • Instagram: • https://instagram.com/ranaalibiologis... TWINS
#############################
