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class="k-card-content"> <div class="k-promo-title k-promo-title-palette-1">Science</div> <div class="k-wording-text">One in 250 million of your father’s sperm managed to navigate a perilous journey to reach your mother’s egg – kick starting the process that made you.</div> <a class="k-fact-link k-fact-link-palette-1 " href="https://web.archive.org/web/20170905233805/http://www.bbc.co.uk/timelines/z84tsg8">What shapes your identity before birth?</a> </div> </div> </div> </div> </div> <div class="b-g-m b-r k-promo-container "> <ul class="k-promos"> <li class="k-social-promo"> <a href="https://web.archive.org/web/20170905233805/https://www.facebook.com/bbciwonder" class="k-promo-link" style="background-color: #3b5999; color: #ffffff;" id="LikeBBCiWonder"> <div class="k-social-promo-wrapper"> <img class="k-social-promo-image" src="https://web.archive.org/web/20170905233805im_/http://ichef.bbci.co.uk/images/ic/48x48/p02460cy.png" alt="Social promo"/> <div class="k-promo-title">Like BBC 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