问题 问答题 论述题

多不饱和脂肪酸(PUFA)的主要来源是什么?在动物体内是如何消化吸收的?

答案

参考答案:来源:

①体内合成;

②植物;

③动物;

④微生物

消化吸收:随饲粮三酰甘油摄入的PUFA在胰脂肪酶的作用下生成二酰甘油或单酰甘油;然后,通过分子扩散进入小肠黏膜,在小肠黏膜细胞内重新合成甘油三酯;然后,与脂蛋白形成乳糜微粒,再分泌到淋巴液,通过胸导管进入全身循环系统,在脂蛋白脂肪酶的作用下释放出游离脂肪酸,在微粒体中短链的不饱和脂肪酸在去饱和酶的延长酶的作用下生成长链不饱和脂肪酸,供各组织器官利用。

阅读理解

阅读短文,选择正确选项。

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