image<\/p>\n\n\n\n
Figure 2\u201373. Polyribosomes from rabbit reticulocytes (Courtesy of \r\nA. Rich; From Levine, 1968). <\/pre>\n\n\n\nThe biochemical composition of ribosomes includes mainly RNA and
proteins with very small quantities of lipids. In its essence they are
ribonucleoproteins \u2014 60% RNA and 40% proteins, which are similar to the
nuclear histones. The proportion RNA\/protein is of the same order for both
subparticles. The rRNA contained in them differ in sedimentation coefficient
and molecular weight. The small subparticle contains rRNA from 16S to
18S with molecular weight of 0.55\u20140.70×10\u2076 daltons, and the large one \u2014
from 23S to 28S with molecular weight of 1.2\u20141.7×10\u2076 daltons varying in
different species. In the large subparticle one more kind of rRNA was
discovered \u2014 5S, with a molecular weight of about 3.0×10\u2074 daltons.
Still, quite a lot are the non-elucidated questions about the structural
organization of ribosomes, the presence and functions of different rRNAs in
them, etc. What is considered undoubted is, that they are the \u201ccell plants\u201d
for synthesizing proteins. Their key position in this process is the reason for
the great interest in them and subsequent numerous investigations.
Especially important is the question on the genesis of ribosomes in the
process of evolving the living systems and about the way of protein
synthesis in precellular forms before their appearance. There are two
possibilities: the first \u2014 they are a result of intracellular differentiation; the
second one \u2014 they have been included from outside, i.e. earlier they have
existed independently. Clarifying this question will shed light on some
aspects of the problem about the origin and evolution of life.<\/p>\n","protected":false},"excerpt":{"rendered":"image Figure 2\u201373. Polyribosomes from rabbit reticulocytes (Courtesy of A. Rich; From Levine, 1968). The biochemical composition of ribosomes includes mainly RNA andproteins with very small quantities of lipids. In its essence they areribonucleoproteins \u2014 60% RNA and 40% proteins, which are similar to thenuclear histones. The proportion RNA\/protein is of the same order for […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[6],"tags":[],"class_list":["post-676","post","type-post","status-publish","format-standard","hentry","category-book"],"_links":{"self":[{"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=\/wp\/v2\/posts\/676","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=676"}],"version-history":[{"count":1,"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=\/wp\/v2\/posts\/676\/revisions"}],"predecessor-version":[{"id":685,"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=\/wp\/v2\/posts\/676\/revisions\/685"}],"wp:attachment":[{"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=676"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=676"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cellandcelldivision.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=676"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}