- \n
- (a) I and II\u00a0\u00a0\u00a0<\/li>\n\n\n\n
- (b) II only\u00a0<\/strong><\/li>\n\n\n\n
- (c) I and III\u00a0\u00a0<\/li>\n\n\n\n
- (d) None of the above statements is correct\u00a0\u00a0<\/li>\n<\/ul>\n\n\n\n
\n
Answer: (b) II only <\/strong><\/p>\n<\/blockquote>\n\n\n\n
- \n
- Rainforests do not produce more oxygen than oceans<\/strong>. The\u00a0ocean, particularly through phytoplankton, is estimated to produce a significantly larger portion of Earth\u2019s oxygen than land-based ecosystems like rainforests<\/strong>.\n
- \n
- While estimates vary, the\u00a0ocean is thought to produce a substantial portion of the world\u2019s oxygen, ranging from 50% to 80%<\/strong>, while land-based ecosystems like rainforests contribute around 28%<\/li>\n<\/ul>\n<\/li>\n\n\n\n
- Marine phytoplankton are primarily responsible for a significant portion of Earth\u2019s oxygen production<\/strong>, with estimates suggesting they produce between 50% and 80% of the oxygen in the atmosphere.\n
- \n
- Synthetic bacteria, while involved in oxygen production in some cases, are not the primary source of oxygen<\/mark><\/strong>\u00a0for the planet<\/li>\n<\/ul>\n<\/li>\n\n\n\n
- The\u00a0concentration of\u00a0dissolved oxygen in surface water<\/strong>\u00a0is much\u00a0lower than the concentration of oxygen in air<\/strong>.<\/mark>\u00a0Air<\/strong>\u00a0contains about\u00a021% oxygen by volume<\/strong>, which is significantly higher than dissolved oxygen levels in water (typically around\u00a08\u201310 mg\/L<\/strong>).<\/mark><\/li>\n<\/ul>\n\n\n\n
![\"\"](\"https:\/\/lotusarise.com\/wp-content\/uploads\/2026\/04\/hypoxia-diagram.jpg\" "\\"\\"")
<\/figure>\n","protected":false},"excerpt":{"rendered":"I. Rain forests produce more oxygen than that produced by oceans. II. Marine phytoplankton and photo synthetic bacteria produce about 50% of the world\u2019s oxygen. III. Well-oxygenated surface water contains several folds higher oxygen than that in atmospheric air. Which of the statements given above is\/are correct? Answer: (b) II only <\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_kad_blocks_custom_css":"","_kad_blocks_head_custom_js":"","_kad_blocks_body_custom_js":"","_kad_blocks_footer_custom_js":"","_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","footnotes":""},"categories":[3,1],"tags":[36],"years":[63],"class_list":["post-2833","post","type-post","status-publish","format-standard","hentry","category-prelims","category-upsc","tag-environment","years-63"],"acf":[],"taxonomy_info":{"category":[{"value":3,"label":"Prelims"},{"value":1,"label":"UPSC"}],"post_tag":[{"value":36,"label":"Environment"}],"years":[{"value":63,"label":"2025"}]},"featured_image_src_large":false,"author_info":{"display_name":"LotusArise","author_link":"https:\/\/lotusarise.com\/qna\/author\/team-lotusarise"},"comment_info":0,"category_info":[{"term_id":3,"name":"Prelims","slug":"prelims","term_group":0,"term_taxonomy_id":3,"taxonomy":"category","description":"","parent":1,"count":1251,"filter":"raw","cat_ID":3,"category_count":1251,"category_description":"","cat_name":"Prelims","category_nicename":"prelims","category_parent":1},{"term_id":1,"name":"UPSC","slug":"upsc","term_group":0,"term_taxonomy_id":1,"taxonomy":"category","description":"","parent":0,"count":1269,"filter":"raw","cat_ID":1,"category_count":1269,"category_description":"","cat_name":"UPSC","category_nicename":"upsc","category_parent":0}],"tag_info":[{"term_id":36,"name":"Environment","slug":"environment","term_group":0,"term_taxonomy_id":36,"taxonomy":"post_tag","description":"","parent":0,"count":193,"filter":"raw"}],"_links":{"self":[{"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/posts\/2833","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/comments?post=2833"}],"version-history":[{"count":0,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/posts\/2833\/revisions"}],"wp:attachment":[{"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/media?parent=2833"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/categories?post=2833"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/tags?post=2833"},{"taxonomy":"years","embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/years?post=2833"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
- The\u00a0concentration of\u00a0dissolved oxygen in surface water<\/strong>\u00a0is much\u00a0lower than the concentration of oxygen in air<\/strong>.<\/mark>\u00a0Air<\/strong>\u00a0contains about\u00a021% oxygen by volume<\/strong>, which is significantly higher than dissolved oxygen levels in water (typically around\u00a08\u201310 mg\/L<\/strong>).<\/mark><\/li>\n<\/ul>\n\n\n\n
- Marine phytoplankton are primarily responsible for a significant portion of Earth\u2019s oxygen production<\/strong>, with estimates suggesting they produce between 50% and 80% of the oxygen in the atmosphere.\n
- While estimates vary, the\u00a0ocean is thought to produce a substantial portion of the world\u2019s oxygen, ranging from 50% to 80%<\/strong>, while land-based ecosystems like rainforests contribute around 28%<\/li>\n<\/ul>\n<\/li>\n\n\n\n