{"id":1388,"date":"2017-01-19T00:18:56","date_gmt":"2017-01-19T00:18:56","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/wm-biology2\/?post_type=chapter&#038;p=1388"},"modified":"2024-04-25T18:49:31","modified_gmt":"2024-04-25T18:49:31","slug":"pathogenic-protists","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/wm-biology2\/chapter\/pathogenic-protists\/","title":{"raw":"Pathogenic Protists","rendered":"Pathogenic Protists"},"content":{"raw":"<div class=\"textbox learning-objectives\">\r\n<h3>Learning Outcomes<\/h3>\r\n<ul>\r\n \t<li>Describe important pathogenic species of protists<\/li>\r\n<\/ul>\r\n<\/div>\r\n<h2>Human Pathogens<\/h2>\r\n<p id=\"fs-idm72108480\">As we have seen, a pathogen is anything that causes disease. Parasitic organisms live in or on a host organism and harm the organism. A small number of protists are serious pathogenic parasites that must infect other organisms to survive and propagate. For example, protist parasites include the causative agents of malaria, African sleeping sickness, amoebic encephalitis, and waterborne gastroenteritis in humans. Other protist pathogens prey on plants, effecting massive destruction of food crops.<\/p>\r\n\r\n<section id=\"fs-idp64587136\" data-depth=\"2\"><\/section>\r\n<h3><em>Plasmodium<\/em> Species<\/h3>\r\n[caption id=\"attachment_1395\" align=\"alignright\" width=\"300\"]<img class=\" wp-image-1395\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/01\/19001006\/Figure_23_04_03.jpg\" alt=\"The micrograph shows round red blood cells, each about 8 microns across, infected with ring-shaped P falciparum.\" width=\"300\" height=\"300\" \/> Figure 1.\u00a0Red blood cells are shown to be infected with <em>P. falciparum.<\/em>\u00a0In this light microscopic image, the ring-shaped <em>P. falciparum<\/em> stains purple. (credit: modification of work by Michael Zahniser; scale-bar data from Matt Russell)[\/caption]\r\n\r\nIn 2015 WHO reported over 200 million cases of malaria, mostly in Africa, South America, and southern Asia. However, it is not well known that malaria was also a prevalent and debilitating disease of the North Central region of the United States, particularly Michigan, with its thousands of lakes and numerous swamps. Prior to the civil war, and the drainage of many swamps, virtually everyone who immigrated to Michigan picked up malaria (<em data-effect=\"italics\">ague<\/em>\u00a0as it was called in the late 1800s), and the pale, sallow, bloated faces of that period were the rule. The only healthy faces were worn by those immigrants who had just arrived. In fact, there were more deaths due to malaria in Michigan than those from the Civil War.\r\n<p id=\"fs-idm57070288\">We now know that malaria is caused by several species of the apicomplexan protist genus\u00a0<em data-effect=\"italics\">Plasmodium<\/em>. Members of\u00a0<em data-effect=\"italics\">Plasmodium<\/em>\u00a0must sequentially require both a mosquito and a vertebrate to complete their life cycle. In vertebrates, the parasite develops in liver cells (the exoerythrocytic stage) and goes on to infect red blood cells (the erythrocytic stage), bursting from and destroying the blood cells with each asexual replication cycle (Figure 1). Of the four\u00a0<em data-effect=\"italics\">Plasmodium<\/em>\u00a0species known to infect humans,\u00a0<em data-effect=\"italics\">P<\/em>.<em data-effect=\"italics\">\u00a0falciparum<\/em>\u00a0accounts for 50 percent of all malaria cases and is the primary (and deadliest) cause of disease-related fatalities in tropical regions of the world. In 2015, it was estimated that malaria caused over 400,000 deaths, mostly in African children.<\/p>\r\nDuring the course of malaria,\u00a0<em data-effect=\"italics\">P<\/em>.<em data-effect=\"italics\">\u00a0falciparum<\/em>\u00a0can infect and destroy more than one-half of a human\u2019s circulating blood cells, leading to severe anemia. In response to waste products released as the parasites burst from infected blood cells, the host immune system mounts a massive inflammatory response with episodes of delirium-inducing fever (paroxysms) as parasites lyse red blood cells, spilling parasite waste into the bloodstream.\u00a0<em data-effect=\"italics\">P<\/em>.<em data-effect=\"italics\">\u00a0falciparum<\/em>\u00a0is transmitted to humans by the African mosquito,\u00a0<em data-effect=\"italics\">Anopheles gambiae<\/em>. Techniques to kill, sterilize, or avoid exposure to this highly aggressive mosquito species are crucial to malaria control. Ironically, a type of genetic control has arisen in parts of the world where malaria is endemic. Possession of one copy of the HbS beta globin allele results in malaria resistance. Unfortunately, this allele also has an unfortunate second effect; when homozygous it causes sickle cell disease.\r\n<div class=\"textbox\">\r\n\r\nThis movie depicts the pathogenesis of <em>Plasmodium falciparum<\/em>, the causative agent of malaria:\r\n\r\n<script type=\"text\/javascript\" src=\"\/\/static.3playmedia.com\/p\/projects\/20361\/files\/1593705\/plugins\/11116.js\"><\/script><script src=\"https:\/\/www.youtube.com\/iframe_api\" type=\"text\/javascript\"><\/script>\r\n<iframe id=\"myytplayer2\" src=\"https:\/\/www.youtube.com\/embed\/BqjMYEfViKA?enablejsapi=1\" width=\"440\" height=\"300\" frameborder=\"0\"><\/iframe>\r\n\r\n<\/div>\r\n<h3>Trypanosomes<\/h3>\r\n[caption id=\"attachment_1396\" align=\"alignright\" width=\"300\"]<img class=\" wp-image-1396\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/01\/19001541\/Figure_23_04_04.jpg\" alt=\"The micrograph shows round red blood cells, about 8 microns across. Swimming among the red blood cells are ribbon-like trypanosomes. The trypanosomes are about three times as long as the red blood cells are wide.\" width=\"300\" height=\"212\" \/> Figure 2.\u00a0Trypanosomes are shown among red blood cells. (credit: modification of work by Dr. Myron G. Shultz; scale-bar data from Matt Russell)[\/caption]\r\n<p id=\"fs-idm79600576\"><em data-effect=\"italics\">Trypanosoma brucei<\/em>\u00a0(Figure 2), transmitted by tsetse flies (<em data-effect=\"italics\">Glossina<\/em>\u00a0spp) in Africa, and related flies in South America, is an flagellated endoparasite responsible for the deadly disease nagana in cattle and horses, and for African sleeping sickness in humans. This trypanosome confounds the human immune system by changing its thick layer of surface glycoproteins with each infectious cycle. (The glycoproteins are identified by the immune system as foreign antigens, and a specific antibody defense is mounted against the parasite.) However,\u00a0<em data-effect=\"italics\">T<\/em>.<em data-effect=\"italics\">\u00a0brucei<\/em>\u00a0has thousands of possible antigens, and with each subsequent generation, the protist switches to a glycoprotein coating with a different molecular structure. In this way,\u00a0<em data-effect=\"italics\">T<\/em>.<em data-effect=\"italics\">\u00a0brucei<\/em>\u00a0is capable of replicating continuously without the immune system ever succeeding in clearing the parasite. Without treatment,\u00a0<em data-effect=\"italics\">T<\/em>.<em data-effect=\"italics\">\u00a0brucei<\/em>\u00a0attacks red blood cells, causing the patient to lapse into a coma and eventually die. During epidemic periods, mortality from the disease can be high. Greater surveillance and control measures lead to a reduction in reported cases; some of the lowest numbers reported in 50 years (fewer than 10,000 cases in all of sub-Saharan Africa) have happened since 2009.<\/p>\r\n\r\n<div class=\"textbox\">\r\n\r\nThis movie discusses the pathogenesis of <em>Trypanosoma brucei<\/em>, the causative agent of African sleeping sickness:\r\n\r\n<script type=\"text\/javascript\" src=\"\/\/static.3playmedia.com\/p\/projects\/20361\/files\/1593714\/plugins\/11085.js\"><\/script><script src=\"https:\/\/www.youtube.com\/iframe_api\" type=\"text\/javascript\"><\/script>\r\n<iframe id=\"myytplayer\" src=\"https:\/\/www.youtube.com\/embed\/4aVUrGO97Zg?enablejsapi=1\" width=\"440\" height=\"300\" frameborder=\"0\"><\/iframe>\r\n\r\n<\/div>\r\n<p id=\"fs-idp62701344\">In Latin America, another species of trypanosome,\u00a0<em data-effect=\"italics\">T<\/em>.<em data-effect=\"italics\">\u00a0cruzi<\/em>, is responsible for Chagas disease.\u00a0<em data-effect=\"italics\">T<\/em>.<em data-effect=\"italics\">\u00a0cruzi<\/em>\u00a0infections are mainly caused by a blood-sucking \u201ckissing bug\u201d in the genus\u00a0<em data-effect=\"italics\">Triatoma<\/em>. These \u201ctrue bugs\u201d bite the host during the night and then defecate on the wound, transmitting the trypanosome to the victim. The victim scratches the wound, further inoculating the site with trypanosomes at the location of the bite. After about 10 weeks, individuals enter the chronic phase but most never develop further symptoms. In about 30 percent of cases, however, the trypanosome causes further damage, especially to the heart and digestive system tissues in the chronic phase of infection, leading to malnutrition and heart failure due to abnormal heart rhythms. An estimated 10 million people are infected with Chagas disease, and it caused 10,000 deaths in 2008.<\/p>\r\n\r\n<h2>Plant Parasites<\/h2>\r\nProtist parasites of terrestrial plants include agents that destroy food crops. The oomycete <em>Plasmopara viticola<\/em> parasitizes grape plants, causing a disease called downy mildew (Figure 3). Grape plants infected with P. viticola appear stunted and have discolored, withered leaves. The spread of downy mildew nearly collapsed the French wine industry in the nineteenth century.\r\n\r\n[caption id=\"attachment_1397\" align=\"aligncenter\" width=\"544\"]<img class=\"size-full wp-image-1397\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/01\/19001623\/Figure_23_04_05.jpg\" alt=\"The photo shows a leaf infected with downy mildew (left) and powdery mildew (right). Where the leaf is infected with downy mildew, it is yellow instead of green. Powdery mildew appears as a white fuzz on the leaf.\" width=\"544\" height=\"384\" \/> Figure 3.\u00a0Both downy and powdery mildews on this grape leaf are caused by an infection of <em>P. viticola<\/em>. (credit: modification of work by USDA)[\/caption]\r\n\r\n[caption id=\"attachment_1398\" align=\"alignright\" width=\"300\"]<img class=\" wp-image-1398\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/01\/19001654\/Figure_23_04_06-e1484785033791.jpg\" alt=\"The photo shows a slice of potato that has browned and appears rotten.\" width=\"300\" height=\"157\" \/> Figure 4.\u00a0These unappetizing remnants result from an infection with <em>P. infestans<\/em>, the causative agent of potato late blight. (credit: USDA)[\/caption]\r\n\r\n<em>Phytophthora infestans<\/em> is an oomycete responsible for potato late blight, which causes potato stalks and stems to decay into black slime (Figure 4). Widespread potato blight caused by <em>P. infestans<\/em> precipitated the well-known Irish potato famine in the nineteenth century that claimed the lives of approximately 1 million people and led to the emigration of at least 1 million more from Ireland. Late blight continues to plague potato crops in certain parts of the United States and Russia, wiping out as much as 70 percent of crops when no pesticides are applied.\r\n<div class=\"textbox tryit\">\r\n<h3>Try It<\/h3>\r\nhttps:\/\/assess.lumenlearning.com\/practice\/55aeaf4d-ccb8-4881-9822-e1033dfd3df6\r\n<\/div>","rendered":"<div class=\"textbox learning-objectives\">\n<h3>Learning Outcomes<\/h3>\n<ul>\n<li>Describe important pathogenic species of protists<\/li>\n<\/ul>\n<\/div>\n<h2>Human Pathogens<\/h2>\n<p id=\"fs-idm72108480\">As we have seen, a pathogen is anything that causes disease. Parasitic organisms live in or on a host organism and harm the organism. A small number of protists are serious pathogenic parasites that must infect other organisms to survive and propagate. For example, protist parasites include the causative agents of malaria, African sleeping sickness, amoebic encephalitis, and waterborne gastroenteritis in humans. Other protist pathogens prey on plants, effecting massive destruction of food crops.<\/p>\n<section id=\"fs-idp64587136\" data-depth=\"2\"><\/section>\n<h3><em>Plasmodium<\/em> Species<\/h3>\n<div id=\"attachment_1395\" style=\"width: 310px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1395\" class=\"wp-image-1395\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/01\/19001006\/Figure_23_04_03.jpg\" alt=\"The micrograph shows round red blood cells, each about 8 microns across, infected with ring-shaped P falciparum.\" width=\"300\" height=\"300\" \/><\/p>\n<p id=\"caption-attachment-1395\" class=\"wp-caption-text\">Figure 1.\u00a0Red blood cells are shown to be infected with <em>P. falciparum.<\/em>\u00a0In this light microscopic image, the ring-shaped <em>P. falciparum<\/em> stains purple. (credit: modification of work by Michael Zahniser; scale-bar data from Matt Russell)<\/p>\n<\/div>\n<p>In 2015 WHO reported over 200 million cases of malaria, mostly in Africa, South America, and southern Asia. However, it is not well known that malaria was also a prevalent and debilitating disease of the North Central region of the United States, particularly Michigan, with its thousands of lakes and numerous swamps. Prior to the civil war, and the drainage of many swamps, virtually everyone who immigrated to Michigan picked up malaria (<em data-effect=\"italics\">ague<\/em>\u00a0as it was called in the late 1800s), and the pale, sallow, bloated faces of that period were the rule. The only healthy faces were worn by those immigrants who had just arrived. In fact, there were more deaths due to malaria in Michigan than those from the Civil War.<\/p>\n<p id=\"fs-idm57070288\">We now know that malaria is caused by several species of the apicomplexan protist genus\u00a0<em data-effect=\"italics\">Plasmodium<\/em>. Members of\u00a0<em data-effect=\"italics\">Plasmodium<\/em>\u00a0must sequentially require both a mosquito and a vertebrate to complete their life cycle. In vertebrates, the parasite develops in liver cells (the exoerythrocytic stage) and goes on to infect red blood cells (the erythrocytic stage), bursting from and destroying the blood cells with each asexual replication cycle (Figure 1). Of the four\u00a0<em data-effect=\"italics\">Plasmodium<\/em>\u00a0species known to infect humans,\u00a0<em data-effect=\"italics\">P<\/em>.<em data-effect=\"italics\">\u00a0falciparum<\/em>\u00a0accounts for 50 percent of all malaria cases and is the primary (and deadliest) cause of disease-related fatalities in tropical regions of the world. In 2015, it was estimated that malaria caused over 400,000 deaths, mostly in African children.<\/p>\n<p>During the course of malaria,\u00a0<em data-effect=\"italics\">P<\/em>.<em data-effect=\"italics\">\u00a0falciparum<\/em>\u00a0can infect and destroy more than one-half of a human\u2019s circulating blood cells, leading to severe anemia. In response to waste products released as the parasites burst from infected blood cells, the host immune system mounts a massive inflammatory response with episodes of delirium-inducing fever (paroxysms) as parasites lyse red blood cells, spilling parasite waste into the bloodstream.\u00a0<em data-effect=\"italics\">P<\/em>.<em data-effect=\"italics\">\u00a0falciparum<\/em>\u00a0is transmitted to humans by the African mosquito,\u00a0<em data-effect=\"italics\">Anopheles gambiae<\/em>. Techniques to kill, sterilize, or avoid exposure to this highly aggressive mosquito species are crucial to malaria control. Ironically, a type of genetic control has arisen in parts of the world where malaria is endemic. Possession of one copy of the HbS beta globin allele results in malaria resistance. Unfortunately, this allele also has an unfortunate second effect; when homozygous it causes sickle cell disease.<\/p>\n<div class=\"textbox\">\n<p>This movie depicts the pathogenesis of <em>Plasmodium falciparum<\/em>, the causative agent of malaria:<\/p>\n<p><script type=\"text\/javascript\" src=\"\/\/static.3playmedia.com\/p\/projects\/20361\/files\/1593705\/plugins\/11116.js\"><\/script><script src=\"https:\/\/www.youtube.com\/iframe_api\" type=\"text\/javascript\"><\/script><br \/>\n<iframe loading=\"lazy\" id=\"myytplayer2\" src=\"https:\/\/www.youtube.com\/embed\/BqjMYEfViKA?enablejsapi=1\" width=\"440\" height=\"300\" frameborder=\"0\"><\/iframe><\/p>\n<\/div>\n<h3>Trypanosomes<\/h3>\n<div id=\"attachment_1396\" style=\"width: 310px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1396\" class=\"wp-image-1396\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/01\/19001541\/Figure_23_04_04.jpg\" alt=\"The micrograph shows round red blood cells, about 8 microns across. Swimming among the red blood cells are ribbon-like trypanosomes. The trypanosomes are about three times as long as the red blood cells are wide.\" width=\"300\" height=\"212\" \/><\/p>\n<p id=\"caption-attachment-1396\" class=\"wp-caption-text\">Figure 2.\u00a0Trypanosomes are shown among red blood cells. (credit: modification of work by Dr. Myron G. Shultz; scale-bar data from Matt Russell)<\/p>\n<\/div>\n<p id=\"fs-idm79600576\"><em data-effect=\"italics\">Trypanosoma brucei<\/em>\u00a0(Figure 2), transmitted by tsetse flies (<em data-effect=\"italics\">Glossina<\/em>\u00a0spp) in Africa, and related flies in South America, is an flagellated endoparasite responsible for the deadly disease nagana in cattle and horses, and for African sleeping sickness in humans. This trypanosome confounds the human immune system by changing its thick layer of surface glycoproteins with each infectious cycle. (The glycoproteins are identified by the immune system as foreign antigens, and a specific antibody defense is mounted against the parasite.) However,\u00a0<em data-effect=\"italics\">T<\/em>.<em data-effect=\"italics\">\u00a0brucei<\/em>\u00a0has thousands of possible antigens, and with each subsequent generation, the protist switches to a glycoprotein coating with a different molecular structure. In this way,\u00a0<em data-effect=\"italics\">T<\/em>.<em data-effect=\"italics\">\u00a0brucei<\/em>\u00a0is capable of replicating continuously without the immune system ever succeeding in clearing the parasite. Without treatment,\u00a0<em data-effect=\"italics\">T<\/em>.<em data-effect=\"italics\">\u00a0brucei<\/em>\u00a0attacks red blood cells, causing the patient to lapse into a coma and eventually die. During epidemic periods, mortality from the disease can be high. Greater surveillance and control measures lead to a reduction in reported cases; some of the lowest numbers reported in 50 years (fewer than 10,000 cases in all of sub-Saharan Africa) have happened since 2009.<\/p>\n<div class=\"textbox\">\n<p>This movie discusses the pathogenesis of <em>Trypanosoma brucei<\/em>, the causative agent of African sleeping sickness:<\/p>\n<p><script type=\"text\/javascript\" src=\"\/\/static.3playmedia.com\/p\/projects\/20361\/files\/1593714\/plugins\/11085.js\"><\/script><script src=\"https:\/\/www.youtube.com\/iframe_api\" type=\"text\/javascript\"><\/script><br \/>\n<iframe loading=\"lazy\" id=\"myytplayer\" src=\"https:\/\/www.youtube.com\/embed\/4aVUrGO97Zg?enablejsapi=1\" width=\"440\" height=\"300\" frameborder=\"0\"><\/iframe><\/p>\n<\/div>\n<p id=\"fs-idp62701344\">In Latin America, another species of trypanosome,\u00a0<em data-effect=\"italics\">T<\/em>.<em data-effect=\"italics\">\u00a0cruzi<\/em>, is responsible for Chagas disease.\u00a0<em data-effect=\"italics\">T<\/em>.<em data-effect=\"italics\">\u00a0cruzi<\/em>\u00a0infections are mainly caused by a blood-sucking \u201ckissing bug\u201d in the genus\u00a0<em data-effect=\"italics\">Triatoma<\/em>. These \u201ctrue bugs\u201d bite the host during the night and then defecate on the wound, transmitting the trypanosome to the victim. The victim scratches the wound, further inoculating the site with trypanosomes at the location of the bite. After about 10 weeks, individuals enter the chronic phase but most never develop further symptoms. In about 30 percent of cases, however, the trypanosome causes further damage, especially to the heart and digestive system tissues in the chronic phase of infection, leading to malnutrition and heart failure due to abnormal heart rhythms. An estimated 10 million people are infected with Chagas disease, and it caused 10,000 deaths in 2008.<\/p>\n<h2>Plant Parasites<\/h2>\n<p>Protist parasites of terrestrial plants include agents that destroy food crops. The oomycete <em>Plasmopara viticola<\/em> parasitizes grape plants, causing a disease called downy mildew (Figure 3). Grape plants infected with P. viticola appear stunted and have discolored, withered leaves. The spread of downy mildew nearly collapsed the French wine industry in the nineteenth century.<\/p>\n<div id=\"attachment_1397\" style=\"width: 554px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1397\" class=\"size-full wp-image-1397\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/01\/19001623\/Figure_23_04_05.jpg\" alt=\"The photo shows a leaf infected with downy mildew (left) and powdery mildew (right). Where the leaf is infected with downy mildew, it is yellow instead of green. Powdery mildew appears as a white fuzz on the leaf.\" width=\"544\" height=\"384\" \/><\/p>\n<p id=\"caption-attachment-1397\" class=\"wp-caption-text\">Figure 3.\u00a0Both downy and powdery mildews on this grape leaf are caused by an infection of <em>P. viticola<\/em>. (credit: modification of work by USDA)<\/p>\n<\/div>\n<div id=\"attachment_1398\" style=\"width: 310px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1398\" class=\"wp-image-1398\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images\/wp-content\/uploads\/sites\/1223\/2017\/01\/19001654\/Figure_23_04_06-e1484785033791.jpg\" alt=\"The photo shows a slice of potato that has browned and appears rotten.\" width=\"300\" height=\"157\" \/><\/p>\n<p id=\"caption-attachment-1398\" class=\"wp-caption-text\">Figure 4.\u00a0These unappetizing remnants result from an infection with <em>P. infestans<\/em>, the causative agent of potato late blight. (credit: USDA)<\/p>\n<\/div>\n<p><em>Phytophthora infestans<\/em> is an oomycete responsible for potato late blight, which causes potato stalks and stems to decay into black slime (Figure 4). Widespread potato blight caused by <em>P. infestans<\/em> precipitated the well-known Irish potato famine in the nineteenth century that claimed the lives of approximately 1 million people and led to the emigration of at least 1 million more from Ireland. Late blight continues to plague potato crops in certain parts of the United States and Russia, wiping out as much as 70 percent of crops when no pesticides are applied.<\/p>\n<div class=\"textbox tryit\">\n<h3>Try It<\/h3>\n<p>\t<iframe id=\"assessment_practice_55aeaf4d-ccb8-4881-9822-e1033dfd3df6\" class=\"resizable\" src=\"https:\/\/assess.lumenlearning.com\/practice\/55aeaf4d-ccb8-4881-9822-e1033dfd3df6?iframe_resize_id=assessment_practice_id_55aeaf4d-ccb8-4881-9822-e1033dfd3df6\" 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-1388\">\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>Biology 2e. <strong>Provided by<\/strong>: OpenStax. <strong>Located at<\/strong>: <a target=\"_blank\" href=\"http:\/\/cnx.org\/contents\/185cbf87-c72e-48f5-b51e-f14f21b5eabd@10.8\">http:\/\/cnx.org\/contents\/185cbf87-c72e-48f5-b51e-f14f21b5eabd@10.8<\/a>. <strong>License<\/strong>: <em><a target=\"_blank\" rel=\"license\" href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY: Attribution<\/a><\/em>. <strong>License Terms<\/strong>: Access for free at https:\/\/openstax.org\/books\/biology-2e\/pages\/1-introduction<\/li><\/ul><div class=\"license-attribution-dropdown-subheading\">All rights reserved content<\/div><ul class=\"citation-list\"><li>Deadliest Parasite on the Planet. <strong>Authored by<\/strong>: Animal Planet. <strong>Located at<\/strong>: <a target=\"_blank\" href=\"https:\/\/youtu.be\/BqjMYEfViKA\">https:\/\/youtu.be\/BqjMYEfViKA<\/a>. <strong>License<\/strong>: <em>All Rights Reserved<\/em>. <strong>License Terms<\/strong>: Standard YouTube License<\/li><li>Death by Tsetse Fly. <strong>Authored by<\/strong>: Animal Planet. <strong>Located at<\/strong>: <a target=\"_blank\" href=\"https:\/\/youtu.be\/4aVUrGO97Zg\">https:\/\/youtu.be\/4aVUrGO97Zg<\/a>. <strong>License<\/strong>: <em>All Rights Reserved<\/em>. <strong>License Terms<\/strong>: Standard YouTube License<\/li><\/ul><\/div>\n\t\t\t\t\t\t <\/div>\n\t\t\t\t\t <\/div>\n\t\t\t <\/section>","protected":false},"author":17,"menu_order":16,"template":"","meta":{"_candela_citation":"[{\"type\":\"cc\",\"description\":\"Biology 2e\",\"author\":\"\",\"organization\":\"OpenStax\",\"url\":\"http:\/\/cnx.org\/contents\/185cbf87-c72e-48f5-b51e-f14f21b5eabd@10.8\",\"project\":\"\",\"license\":\"cc-by\",\"license_terms\":\"Access for free at https:\/\/openstax.org\/books\/biology-2e\/pages\/1-introduction\"},{\"type\":\"copyrighted_video\",\"description\":\"Deadliest Parasite on the Planet\",\"author\":\"Animal Planet\",\"organization\":\"\",\"url\":\"https:\/\/youtu.be\/BqjMYEfViKA\",\"project\":\"\",\"license\":\"arr\",\"license_terms\":\"Standard YouTube License\"},{\"type\":\"copyrighted_video\",\"description\":\"Death by Tsetse Fly\",\"author\":\"Animal Planet\",\"organization\":\"\",\"url\":\"https:\/\/youtu.be\/4aVUrGO97Zg\",\"project\":\"\",\"license\":\"arr\",\"license_terms\":\"Standard YouTube License\"}]","CANDELA_OUTCOMES_GUID":"1fc529e4-f530-43c9-a3ac-bdcddedfbefb, 1986f50d-fb3e-4eb2-9808-3abc3463fd68","pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-1388","chapter","type-chapter","status-publish","hentry"],"part":19,"_links":{"self":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/chapters\/1388","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/wp\/v2\/users\/17"}],"version-history":[{"count":12,"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/chapters\/1388\/revisions"}],"predecessor-version":[{"id":8329,"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/chapters\/1388\/revisions\/8329"}],"part":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/parts\/19"}],"metadata":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/chapters\/1388\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/wp\/v2\/media?parent=1388"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/pressbooks\/v2\/chapter-type?post=1388"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/wp\/v2\/contributor?post=1388"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/wm-biology2\/wp-json\/wp\/v2\/license?post=1388"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}