of triglycerides decreased (from $1.5\\text{ mmol dm}^{-3}$ to $0.0\\text{ mmol dm}^{-3}$) and the concentration of monoglycerides increased (from $3.4\\text{ mmol dm}^{-3}$ to $5.2\\text{ mmol dm}^{-3}$) M1\n- because triglycerides are digested / hydrolysed by lipase; A1\n- which breaks the ester bonds (releasing monoglycerides and fatty acids). A1","marks":3,"order":0,"markingRubric":null,"explanation":null,"options":[]},{"id":"9dfa8c89-17f3-44dd-b5f2-3c099798e262","label":"2","content":"Immediately after withdrawing each sample, the scientist placed it in a water bath at \$95^\\circ\\text{C}\$ for 10 minutes. Explain why.","markscheme":"- To denature the lipase (and any other enzymes present); M1\n- so that digestion / hydrolysis of triglycerides stopped immediately at the time of sampling. A1","marks":2,"order":1,"markingRubric":null,"explanation":null,"options":[]},{"id":"fe280289-49b5-4dbe-8d7b-dd5f2dd32028","label":"3","content":"Describe the role of micelles in the absorption of monoglycerides and fatty acids into the epithelial cells of the small intestine.","markscheme":"- Micelles associate bile salts with fatty acids and monoglycerides, making them water-soluble; M1\n- They carry / transport monoglycerides and fatty acids to the membrane of the epithelial cells / enterocytes; A1\n- This maintains a high concentration gradient of monoglycerides and fatty acids at the cell surface, allowing them to enter the cell by simple diffusion. A1","marks":3,"order":2,"markingRubric":null,"explanation":null,"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null}],"subjectCode":"a_level_biology__aqa","summaries":[{"id":"02acb2ae-7270-466c-8286-f1b676c40eee","difficultyBand":"medium","calculatorUse":null,"totalMarks":7},{"id":"43fbae02-37e9-4add-be91-77b74ebb4b3a","difficultyBand":"medium","calculatorUse":null,"totalMarks":7},{"id":"49d73383-2221-4feb-8bfa-a9dd6de343aa","difficultyBand":"medium","calculatorUse":null,"totalMarks":9},{"id":"50538783-4ffd-4b4e-bb56-7252eeaa3e25","difficultyBand":"medium","calculatorUse":null,"totalMarks":9},{"id":"55bffb37-f86d-4c58-b552-ad2dab7b41db","difficultyBand":"medium","calculatorUse":null,"totalMarks":8},{"id":"6f258bbe-94a6-4581-aa54-d1f267b06f11","difficultyBand":"medium","calculatorUse":null,"totalMarks":10},{"id":"81a9eb09-f98c-47a1-b8d5-250ffdee8703","difficultyBand":"medium","calculatorUse":null,"totalMarks":7},{"id":"864979b2-9f95-40f5-8b8c-ae639046bb2b","difficultyBand":"medium","calculatorUse":null,"totalMarks":8},{"id":"8e55854c-c072-4560-ab62-5ba6ec44c9b6","difficultyBand":"medium","calculatorUse":null,"totalMarks":7},{"id":"a2efe4cf-1a1c-4696-9bc5-21ac6714259e","difficultyBand":"medium","calculatorUse":null,"totalMarks":7},{"id":"b5a8656f-1894-4edd-84d1-4c7bb4ab6c87","difficultyBand":"medium","calculatorUse":null,"totalMarks":8},{"id":"eca1f0f0-e8b0-4694-a366-671b102a4fc6","difficultyBand":"medium","calculatorUse":null,"totalMarks":8}],"title":"Digestion and absorption","topicId":"dd29829e-a59f-59d7-ac05-7c6fccd26479","topicSidebar":"$L42","topicSlug":"digestion-and-absorption","topicTitle":"Digestion and absorption"}]}],"$L43"]}]

Digestion and absorption

Question 10

Digestion and absorption Questions

Digestion and absorption

Question 10

Digestion and absorption Questions