Also, the inner lining of the stomach has millions of tiny gastric pits that dive down to gastric glands.

，的内表面有无数密集分布的小凹，腺即开口于小凹的底部。

Raptors have an especially deep fovea— a depression in the back of their eye that fits more photoreceptors.

猛禽有一个特别深的中央凹— —它们眼睛后部的凹陷处适合更多的光感受器。

The teeth of Baryonyx are very sharp and pointed, but they're actually quite round and they have a fluted pattern along one side.

重爪龙的牙齿尖锐锋利，但实际上这些牙齿有弧度，一侧内凹。