{"id":2929,"date":"2016-06-15T20:54:58","date_gmt":"2016-06-15T20:54:58","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/biologyxwaymakerxmaster\/?post_type=chapter&#038;p=2929"},"modified":"2024-04-29T16:33:39","modified_gmt":"2024-04-29T16:33:39","slug":"reading-polygenic-inheritance-and-environmental-effects","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/wm-biology1\/chapter\/reading-polygenic-inheritance-and-environmental-effects\/","title":{"raw":"Polygenic Inheritance and Environmental Effects","rendered":"Polygenic Inheritance and Environmental Effects"},"content":{"raw":"<div class=\"textbox learning-objectives\">\r\n<h3>Learning Outcomes<\/h3>\r\n<ul>\r\n \t<li>Describe polygenic inheritance and how to recognize it<\/li>\r\n \t<li>Describe continuous variation and how to recognize it<\/li>\r\n<\/ul>\r\n<\/div>\r\n<h2>How is Height Inherited?<\/h2>\r\nMany heritable human characteristics don\u2019t seem to follow Mendelian rules in their inheritance patterns. For example, consider human height. Unlike a simple Mendelian characteristic, human height displays:\r\n<ul>\r\n \t<li><strong>Continuous variation.<\/strong> Unlike Mendel's pea plants, humans don\u2019t come in two clear-cut \u201ctall\u201d and \u201cshort\u201d varieties. In fact, they don't even come in four heights, or eight, or sixteen. Instead, it\u2019s possible to get humans of many different heights, and height can vary in increments of inches or fractions of inches. As an example, consider the bell curve-shaped graph in Figure 1, which shows the heights of a group of male high school seniors.<\/li>\r\n \t<li><strong>A complex inheritance pattern.<\/strong> If you've paid attention to the heights of your friends and family, you may have noticed that many different patterns of inheritance are possible. Tall parents can have a short child, short parents can have a tall child, and two parents of different heights may or may not have a child of intermediate height. In addition, siblings with the same two parents may have a range of heights, ones that don't fall into clear, distinct categories. Simple models involving one or two genes can't accurately predict all of these inheritance patterns.<\/li>\r\n<\/ul>\r\n[caption id=\"attachment_2932\" align=\"alignright\" width=\"400\"]<img class=\"wp-image-2932\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/110\/2016\/06\/15204204\/height-1024x631.png\" alt=\" Histogram showing height in inches of male high school seniors in a sample group. The histogram is roughly bell-shaped, with just a few individuals at the tails (60 inches and 77 inches) and many individuals in the middle, around 69 inches.\" width=\"400\" height=\"246\" \/> Figure 1. Heights of male high school seniors. Image modified from \"<a href=\"http:\/\/users.rcn.com\/jkimball.ma.ultranet\/BiologyPages\/Q\/QTL.html\" target=\"_blank\" rel=\"noopener\">Continuous variation: Quantitative traits<\/a>,\" by J. W. Kimball (CC BY 3.0).[\/caption]\r\n\r\nHow, then, is height inherited? Height and other similar features are controlled not just by one gene, but rather, by multiple (often many) genes that each make a small contribution to the overall outcome. This inheritance pattern is called <strong>polygenic inheritance<\/strong> (<em>poly<\/em>- = many). For instance, a recent study found over 400 genes linked to variation in height[footnote]Wood, A. R., Esko, T., Yang, J., Vedantam, S., Pers, T. H., Gustafsson, S., ... Frayling, T. M. (2014). Defining the role of common variation in the genomic and biological architecture of adult human height. <em>Nature Genetics<\/em>, <em>46<\/em>, 1173\u20131186. <a href=\"http:\/\/dx.doi.org\/10.1038\/ng.3097\" target=\"_blank\" rel=\"noopener\">http:\/\/dx.doi.org\/10.1038\/ng.3097<\/a>.[\/footnote].\u00a0When there are large numbers of genes involved, it becomes hard to distinguish the effect of each individual gene, and even harder to see that gene variants (alleles) are inherited according to Mendelian rules. In a further complication, height doesn\u2019t just depend on genetics: it also depends a lot on environmental factors, such as a child\u2019s overall health and the type of nutrition they receive while growing up.\r\n\r\nIn this article, we\u2019ll look in more detail at how complex human traits such as height are inherited, as well as how factors like genetic background and environment can influence the <strong>phenotype<\/strong> (observable features) produced by a particular <strong>genotype<\/strong> (set of gene variants, or alleles).\r\n<h2>Polygenic Inheritance<\/h2>\r\nSome human characteristics, such as height, eye color, and hair color, don\u2019t come in just a few distinct forms. Instead, they vary in small gradations, forming a spectrum or continuum of possible phenotypes. Features like these are called quantitative characters, and they\u2019re typically controlled by multiple genes (often, many genes), each of which contributes to the overall phenotype. For example, although there are two major eye color genes, there are at least 14 additional genes that play roles in determining a person\u2019s exact eye color[footnote]White, D. and Rabago-Smith, M. (2011). Genotype-phenotype associations and human eye color. <em>Journal of Human Genetics<\/em>, <em>56<\/em>, 5\u20137. <a href=\"http:\/\/dx.doi.org\/10.1038\/jhg.2010.126\" target=\"_blank\" rel=\"noopener\">http:\/\/dx.doi.org\/10.1038\/jhg.2010.126<\/a>.[\/footnote].\r\n\r\nLooking at a real example of a human polygenic trait would get complicated, largely because we\u2019d have to keep track of tens, or even hundreds, of different allele pairs. However, we can use an example involving the color of wheat kernels to see how Mendelian inheritance of multiple genes (plus a little incomplete dominance of alleles) can produce a broad spectrum of phenotypes[footnote]Kimball, J. W. (2011, March 8). Continuous variation: Quantitative traits. Retrieved from\u00a0<a href=\"http:\/\/users.rcn.com\/jkimball.ma.ultranet\/BiologyPages\/Q\/QTL.html\" target=\"_blank\" rel=\"noopener\">http:\/\/users.rcn.com\/jkimball.ma.ultranet\/BiologyPages\/Q\/QTL.html<\/a>.[\/footnote]. In this example, there are three genes that make reddish pigment in wheat kernels, which we\u2019ll call <em>A<\/em>, <em>B<\/em>, and <em>C<\/em>. Each comes in two alleles, one of which makes a unit of pigment (the capital-letter allele) and one of which does not make any pigment (the lowercase allele). Thus, the <em>aa<\/em> genotype would contribute zero units of pigment, the <em>Aa<\/em> genotype would contribute one unit, and the <em>AA<\/em> genotype would contribute two\u2014basically, a form of incomplete dominance.\r\n\r\n<img class=\"aligncenter size-large wp-image-2933\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/110\/2016\/06\/15204737\/punnet-1024x948.png\" alt=\"64-square Punnett square illustrating the phenotypes of the offspring of an AaBbCc x AaBbCc cross (in which each uppercase allele contributes one unit of pigment, while each lowercase allele contributes zero units of pigment). Of the 64 squares in the chart: 1 square produces a very very dark red phenotype (six units of pigment) 6 squares produce a very dark red phenotype (five units of pigment) 15 squares produce a dark red phenotype (four units of pigment). 20 squares produce a red phenotype (three units of pigment) 15 squares produce a light red phenotype (two units of pigment) 6 squares produce a very light red phenotype (one unit of pigment) 1 square produces a white phenotype (no units of pigment)\" width=\"1024\" height=\"948\" \/>\r\n\r\nNow, let\u2019s imagine that two plants heterozygous for all three genes (<em>AaBbCc<\/em>) were crossed to one another (or, equivalently, allowed to self-fertilize). Each of the parent plants would have three units of pigment, or pinkish kernels. Their offspring, however, could display seven different categories of phenotypes, ranging from zero units of pigment (<em>aabbcc<\/em>) and pure white kernels to six units of pigment (<em>AABBCC<\/em>) and dark red kernels, with the intermediate phenotypes being most common.\r\n\r\nThis example illustrates how we can get a spectrum of slightly different phenotypes (something approaching continuous variation) with just three genes whose alleles display incomplete dominance. It\u2019s not hard to imagine that, as we increased the number of genes involved, we\u2019d be able to get even finer variations in color, or in another trait such as height. Real polygenic traits aren\u2019t usually quite this clean and simple. (For instance, genes may make unequal contributions to the phenotype, alleles may or may not display incomplete dominance, and there may be non-additive interactions between genes.) However, the basic idea\u2014that multiple genes obeying Mendelian rules can produce a spectrum of finely differing phenotypes\u2014holds true for human traits such as skin and eye color.\r\n<div class=\"textbox exercises\">\r\n<h3>PRactice Questions<\/h3>\r\nWe've learned about polygenic inheritance and continuous variation. Just what is the difference between these two types of inheritance?\r\n\r\n[practice-area rows=\"4\"][\/practice-area]\r\n[reveal-answer q=\"646463\"]Show Answer[\/reveal-answer]\r\n[hidden-answer a=\"646463\"]<em>Polygenic traits<\/em> are traits that rely on multiple genes. <em>Continuous variation<\/em> describes traits whose phenotypes occur on a continuum, rather than having a limited number of possible phenotypes. Traits with continuous variation are often also polygenic traits, but not always, and not all polygenic traits have continuous variation.[\/hidden-answer]\r\n\r\n<\/div>\r\n<div class=\"textbox tryit\">\r\n<h3>Try It<\/h3>\r\nhttps:\/\/assess.lumenlearning.com\/practice\/97f91fa3-42e7-43bb-b98c-cd1a2a86c8c1\r\nhttps:\/\/assess.lumenlearning.com\/practice\/7008539b-c5e1-4012-8fc7-a02e42c8db0f\r\n<\/div>","rendered":"<div class=\"textbox learning-objectives\">\n<h3>Learning Outcomes<\/h3>\n<ul>\n<li>Describe polygenic inheritance and how to recognize it<\/li>\n<li>Describe continuous variation and how to recognize it<\/li>\n<\/ul>\n<\/div>\n<h2>How is Height Inherited?<\/h2>\n<p>Many heritable human characteristics don\u2019t seem to follow Mendelian rules in their inheritance patterns. For example, consider human height. Unlike a simple Mendelian characteristic, human height displays:<\/p>\n<ul>\n<li><strong>Continuous variation.<\/strong> Unlike Mendel&#8217;s pea plants, humans don\u2019t come in two clear-cut \u201ctall\u201d and \u201cshort\u201d varieties. In fact, they don&#8217;t even come in four heights, or eight, or sixteen. Instead, it\u2019s possible to get humans of many different heights, and height can vary in increments of inches or fractions of inches. As an example, consider the bell curve-shaped graph in Figure 1, which shows the heights of a group of male high school seniors.<\/li>\n<li><strong>A complex inheritance pattern.<\/strong> If you&#8217;ve paid attention to the heights of your friends and family, you may have noticed that many different patterns of inheritance are possible. Tall parents can have a short child, short parents can have a tall child, and two parents of different heights may or may not have a child of intermediate height. In addition, siblings with the same two parents may have a range of heights, ones that don&#8217;t fall into clear, distinct categories. Simple models involving one or two genes can&#8217;t accurately predict all of these inheritance patterns.<\/li>\n<\/ul>\n<div id=\"attachment_2932\" style=\"width: 410px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-2932\" class=\"wp-image-2932\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/110\/2016\/06\/15204204\/height-1024x631.png\" alt=\"Histogram showing height in inches of male high school seniors in a sample group. The histogram is roughly bell-shaped, with just a few individuals at the tails (60 inches and 77 inches) and many individuals in the middle, around 69 inches.\" width=\"400\" height=\"246\" \/><\/p>\n<p id=\"caption-attachment-2932\" class=\"wp-caption-text\">Figure 1. Heights of male high school seniors. Image modified from &#8220;<a href=\"http:\/\/users.rcn.com\/jkimball.ma.ultranet\/BiologyPages\/Q\/QTL.html\" target=\"_blank\" rel=\"noopener\">Continuous variation: Quantitative traits<\/a>,&#8221; by J. W. Kimball (CC BY 3.0).<\/p>\n<\/div>\n<p>How, then, is height inherited? Height and other similar features are controlled not just by one gene, but rather, by multiple (often many) genes that each make a small contribution to the overall outcome. This inheritance pattern is called <strong>polygenic inheritance<\/strong> (<em>poly<\/em>&#8211; = many). For instance, a recent study found over 400 genes linked to variation in height<a class=\"footnote\" title=\"Wood, A. R., Esko, T., Yang, J., Vedantam, S., Pers, T. H., Gustafsson, S., ... Frayling, T. M. (2014). Defining the role of common variation in the genomic and biological architecture of adult human height. Nature Genetics, 46, 1173\u20131186. http:\/\/dx.doi.org\/10.1038\/ng.3097.\" id=\"return-footnote-2929-1\" href=\"#footnote-2929-1\" aria-label=\"Footnote 1\"><sup class=\"footnote\">[1]<\/sup><\/a>.\u00a0When there are large numbers of genes involved, it becomes hard to distinguish the effect of each individual gene, and even harder to see that gene variants (alleles) are inherited according to Mendelian rules. In a further complication, height doesn\u2019t just depend on genetics: it also depends a lot on environmental factors, such as a child\u2019s overall health and the type of nutrition they receive while growing up.<\/p>\n<p>In this article, we\u2019ll look in more detail at how complex human traits such as height are inherited, as well as how factors like genetic background and environment can influence the <strong>phenotype<\/strong> (observable features) produced by a particular <strong>genotype<\/strong> (set of gene variants, or alleles).<\/p>\n<h2>Polygenic Inheritance<\/h2>\n<p>Some human characteristics, such as height, eye color, and hair color, don\u2019t come in just a few distinct forms. Instead, they vary in small gradations, forming a spectrum or continuum of possible phenotypes. Features like these are called quantitative characters, and they\u2019re typically controlled by multiple genes (often, many genes), each of which contributes to the overall phenotype. For example, although there are two major eye color genes, there are at least 14 additional genes that play roles in determining a person\u2019s exact eye color<a class=\"footnote\" title=\"White, D. and Rabago-Smith, M. (2011). Genotype-phenotype associations and human eye color. Journal of Human Genetics, 56, 5\u20137. http:\/\/dx.doi.org\/10.1038\/jhg.2010.126.\" id=\"return-footnote-2929-2\" href=\"#footnote-2929-2\" aria-label=\"Footnote 2\"><sup class=\"footnote\">[2]<\/sup><\/a>.<\/p>\n<p>Looking at a real example of a human polygenic trait would get complicated, largely because we\u2019d have to keep track of tens, or even hundreds, of different allele pairs. However, we can use an example involving the color of wheat kernels to see how Mendelian inheritance of multiple genes (plus a little incomplete dominance of alleles) can produce a broad spectrum of phenotypes<a class=\"footnote\" title=\"Kimball, J. W. (2011, March 8). Continuous variation: Quantitative traits. Retrieved from\u00a0http:\/\/users.rcn.com\/jkimball.ma.ultranet\/BiologyPages\/Q\/QTL.html.\" id=\"return-footnote-2929-3\" href=\"#footnote-2929-3\" aria-label=\"Footnote 3\"><sup class=\"footnote\">[3]<\/sup><\/a>. In this example, there are three genes that make reddish pigment in wheat kernels, which we\u2019ll call <em>A<\/em>, <em>B<\/em>, and <em>C<\/em>. Each comes in two alleles, one of which makes a unit of pigment (the capital-letter allele) and one of which does not make any pigment (the lowercase allele). Thus, the <em>aa<\/em> genotype would contribute zero units of pigment, the <em>Aa<\/em> genotype would contribute one unit, and the <em>AA<\/em> genotype would contribute two\u2014basically, a form of incomplete dominance.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-large wp-image-2933\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/110\/2016\/06\/15204737\/punnet-1024x948.png\" alt=\"64-square Punnett square illustrating the phenotypes of the offspring of an AaBbCc x AaBbCc cross (in which each uppercase allele contributes one unit of pigment, while each lowercase allele contributes zero units of pigment). Of the 64 squares in the chart: 1 square produces a very very dark red phenotype (six units of pigment) 6 squares produce a very dark red phenotype (five units of pigment) 15 squares produce a dark red phenotype (four units of pigment). 20 squares produce a red phenotype (three units of pigment) 15 squares produce a light red phenotype (two units of pigment) 6 squares produce a very light red phenotype (one unit of pigment) 1 square produces a white phenotype (no units of pigment)\" width=\"1024\" height=\"948\" \/><\/p>\n<p>Now, let\u2019s imagine that two plants heterozygous for all three genes (<em>AaBbCc<\/em>) were crossed to one another (or, equivalently, allowed to self-fertilize). Each of the parent plants would have three units of pigment, or pinkish kernels. Their offspring, however, could display seven different categories of phenotypes, ranging from zero units of pigment (<em>aabbcc<\/em>) and pure white kernels to six units of pigment (<em>AABBCC<\/em>) and dark red kernels, with the intermediate phenotypes being most common.<\/p>\n<p>This example illustrates how we can get a spectrum of slightly different phenotypes (something approaching continuous variation) with just three genes whose alleles display incomplete dominance. It\u2019s not hard to imagine that, as we increased the number of genes involved, we\u2019d be able to get even finer variations in color, or in another trait such as height. Real polygenic traits aren\u2019t usually quite this clean and simple. (For instance, genes may make unequal contributions to the phenotype, alleles may or may not display incomplete dominance, and there may be non-additive interactions between genes.) However, the basic idea\u2014that multiple genes obeying Mendelian rules can produce a spectrum of finely differing phenotypes\u2014holds true for human traits such as skin and eye color.<\/p>\n<div class=\"textbox exercises\">\n<h3>PRactice Questions<\/h3>\n<p>We&#8217;ve learned about polygenic inheritance and continuous variation. Just what is the difference between these two types of inheritance?<\/p>\n<p><textarea aria-label=\"Your Answer\" rows=\"4\"><\/textarea><\/p>\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"q646463\">Show Answer<\/span><\/p>\n<div id=\"q646463\" class=\"hidden-answer\" style=\"display: none\"><em>Polygenic traits<\/em> are traits that rely on multiple genes. <em>Continuous variation<\/em> describes traits whose phenotypes occur on a continuum, rather than having a limited number of possible phenotypes. Traits with continuous variation are often also polygenic traits, but not always, and not all polygenic traits have continuous variation.<\/div>\n<\/div>\n<\/div>\n<div class=\"textbox tryit\">\n<h3>Try It<\/h3>\n<p>\t<iframe id=\"assessment_practice_97f91fa3-42e7-43bb-b98c-cd1a2a86c8c1\" class=\"resizable\" src=\"https:\/\/assess.lumenlearning.com\/practice\/97f91fa3-42e7-43bb-b98c-cd1a2a86c8c1?iframe_resize_id=assessment_practice_id_97f91fa3-42e7-43bb-b98c-cd1a2a86c8c1\" frameborder=\"0\" style=\"border:none;width:100%;height:100%;min-height:300px;\"><br \/>\n\t<\/iframe><br \/>\n\t<iframe id=\"assessment_practice_7008539b-c5e1-4012-8fc7-a02e42c8db0f\" class=\"resizable\" src=\"https:\/\/assess.lumenlearning.com\/practice\/7008539b-c5e1-4012-8fc7-a02e42c8db0f?iframe_resize_id=assessment_practice_id_7008539b-c5e1-4012-8fc7-a02e42c8db0f\" frameborder=\"0\" style=\"border:none;width:100%;height:100%;min-height:300px;\"><br \/>\n\t<\/iframe>\n<\/div>\n\n\t\t\t <section class=\"citations-section\" role=\"contentinfo\">\n\t\t\t <h3>Candela Citations<\/h3>\n\t\t\t\t\t <div>\n\t\t\t\t\t\t <div id=\"citation-list-2929\">\n\t\t\t\t\t\t\t <div class=\"licensing\"><div class=\"license-attribution-dropdown-subheading\">CC licensed content, Shared previously<\/div><ul class=\"citation-list\"><li>Polygenic inheritance and environmental effects. <strong>Provided by<\/strong>: Khan Academy. <strong>Located at<\/strong>: <a target=\"_blank\" href=\"https:\/\/www.khanacademy.org\/science\/biology\/classical-genetics\/variations-on-mendelian-genetics\/a\/polygenic-inheritance-and-environmental-effects\">https:\/\/www.khanacademy.org\/science\/biology\/classical-genetics\/variations-on-mendelian-genetics\/a\/polygenic-inheritance-and-environmental-effects<\/a>. <strong>License<\/strong>: <em><a target=\"_blank\" rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/4.0\/\">CC BY-NC-SA: Attribution-NonCommercial-ShareAlike<\/a><\/em><\/li><\/ul><\/div>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t <\/div>\n\t\t\t <\/section><hr class=\"before-footnotes clear\" \/><div class=\"footnotes\"><ol><li id=\"footnote-2929-1\">Wood, A. R., Esko, T., Yang, J., Vedantam, S., Pers, T. H., Gustafsson, S., ... Frayling, T. M. (2014). Defining the role of common variation in the genomic and biological architecture of adult human height. <em>Nature Genetics<\/em>, <em>46<\/em>, 1173\u20131186. <a href=\"http:\/\/dx.doi.org\/10.1038\/ng.3097\" target=\"_blank\" rel=\"noopener\">http:\/\/dx.doi.org\/10.1038\/ng.3097<\/a>. <a href=\"#return-footnote-2929-1\" class=\"return-footnote\" aria-label=\"Return to footnote 1\">&crarr;<\/a><\/li><li id=\"footnote-2929-2\">White, D. and Rabago-Smith, M. (2011). Genotype-phenotype associations and human eye color. <em>Journal of Human Genetics<\/em>, <em>56<\/em>, 5\u20137. <a href=\"http:\/\/dx.doi.org\/10.1038\/jhg.2010.126\" target=\"_blank\" rel=\"noopener\">http:\/\/dx.doi.org\/10.1038\/jhg.2010.126<\/a>. <a href=\"#return-footnote-2929-2\" class=\"return-footnote\" aria-label=\"Return to footnote 2\">&crarr;<\/a><\/li><li id=\"footnote-2929-3\">Kimball, J. W. (2011, March 8). Continuous variation: Quantitative traits. Retrieved from\u00a0<a href=\"http:\/\/users.rcn.com\/jkimball.ma.ultranet\/BiologyPages\/Q\/QTL.html\" target=\"_blank\" rel=\"noopener\">http:\/\/users.rcn.com\/jkimball.ma.ultranet\/BiologyPages\/Q\/QTL.html<\/a>. <a href=\"#return-footnote-2929-3\" class=\"return-footnote\" aria-label=\"Return to footnote 3\">&crarr;<\/a><\/li><\/ol><\/div>","protected":false},"author":17,"menu_order":18,"template":"","meta":{"_candela_citation":"[{\"type\":\"cc\",\"description\":\"Polygenic inheritance and environmental effects\",\"author\":\"\",\"organization\":\"Khan Academy\",\"url\":\"https:\/\/www.khanacademy.org\/science\/biology\/classical-genetics\/variations-on-mendelian-genetics\/a\/polygenic-inheritance-and-environmental-effects\",\"project\":\"\",\"license\":\"cc-by-nc-sa\",\"license_terms\":\"\"}]","CANDELA_OUTCOMES_GUID":"463c4e68-c448-49ab-8747-d1097eea46d4, 6d19462e-bdfe-4b45-bb37-7ec3153dddca, 95a66bb1-744e-4ea9-9a94-fc7cd907914c","pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-2929","chapter","type-chapter","status-publish","hentry"],"part":258,"_links":{"self":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology1\/wp-json\/pressbooks\/v2\/chapters\/2929","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology1\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology1\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/wm-biology1\/wp-json\/wp\/v2\/users\/17"}],"version-history":[{"count":17,"href":"https:\/\/courses.lumenlearning.com\/wm-biology1\/wp-json\/pressbooks\/v2\/chapters\/2929\/revisions"}],"predecessor-version":[{"id":6015,"href":"https:\/\/courses.lumenlearning.com\/wm-biology1\/wp-json\/pressbooks\/v2\/chapters\/2929\/revisions\/6015"}],"part":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology1\/wp-json\/pressbooks\/v2\/parts\/258"}],"metadata":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology1\/wp-json\/pressbooks\/v2\/chapters\/2929\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology1\/wp-json\/wp\/v2\/media?parent=2929"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/wm-biology1\/wp-json\/pressbooks\/v2\/chapter-type?post=2929"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/wm-biology1\/wp-json\/wp\/v2\/contributor?post=2929"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/wm-biology1\/wp-json\/wp\/v2\/license?post=2929"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}