eyes and vision - part 5 of 17. explains the structure and functions of the human eye and describes the complicated mechanism of human vision: how the retinal image is inverted; how the lens focuses; and how the pupils regulate the amount of light enterin - 鞏膜 個影片檔及 b 捲影像00:32
close-up of the eyes of a girl who is looking at the camera front view. black and white video. - 鞏膜 個影片檔及 b 捲影像00:12