Find out what bacteria are and why some are harmful while others are essential for life in this free KS3 Biology worksheet — no preparation needed, just download and use. Perfect as a lesson starter, homework task, or quick revision activity for students aged 11-14.

This free taster worksheet contains three questions worth 13 marks: a multiple choice question testing knowledge of what bacteria are and their structure; a fill-in-the-blank passage using five key terms including unicellular, microorganism, cell wall, cytoplasm, and nucleus; and a short answer question asking students to give examples of helpful and harmful bacteria with explanations. A full answer key with detailed marking guidance is included as a separate file.

Want more? The full 100-mark premium worksheet goes deeper into the role of gut flora in the digestive system, how bacteria produce enzymes to digest food the body cannot break down alone, how gut bacteria compete with harmful pathogens to protect health, and what damages gut bacteria and how to restore it. A complete lesson bundle combining the full worksheet and extension activities is also available on the iNewittAll TES store.

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The accompanying YouTube video is Google Classroom ready — simply copy the link directly into your Classroom assignment.

Last updated: — initial release

TAGS:
bacteria, digestive system, gut bacteria, gut flora, KS3 biology, KS3 science, microorganisms, pathogens, unicellular, free worksheet, biology revision, year 7 biology, year 8 biology, homework help, revision resource

PRICE:
Free

KEY STAGE:
KS3

SUBJECT:
Biology