Final answer:
The middle smooth muscle layer of the uterine tube, known as the myometrium, is responsible for the peristaltic contractions that assist in moving the oocyte towards the uterus.
Step-by-step explanation:
The layer responsible for the peristaltic contractions that help move an oocyte along the uterine tube (also known as fallopian tubes or oviducts) is the middle smooth muscle layer, called the myometrium. The uterine tube is made up of three distinct layers: an outer serosa, the middle myometrial layer consisting of smooth muscle, and an inner mucosal layer. High levels of estrogen around the time of ovulation induce intervals of contractions in these smooth muscles, which occur every 4 to 8 seconds.
This action, in concert with the coordinated beating cilia of the inner mucosal layer, generates a current flowing towards the uterus, thus facilitating the movement of the secondary oocyte surrounded by granulosa cells (the oocyte-granulosa cell complex) into the interior of the tube and slowly towards the uterus.