In a frog embryo, gastrulation . In a frog embryo, gastrulation . produces a blastocoel displaced into the animal hemisphere occurs along the primitive streak in the animal hemisphere occurs within the inner cell mass that is embedded in the large amount of yolk proceeds by involution as cells roll over the lip of the blastopore

How had the study of mitosis affected scientists knowledge of cancer

The hypothesis of continental drift states that earth's continents, which are located on tectonic plates, move relative to each other. which of the following is true of the movement of the tectonic plates? a. tectonic plates only move once every million years. b. they move at a rate of approximately 5 centimeters per year. c. tectonic plates never move, only the continents located on them do. d. their movements are very rapid and occur at random times.

Select the correct answer from each drop-down menu. in an experiment, dr. travis examined the effects of calcium intake on osteoporosis, a condition that causes an increased risk of bone fractures. the amount of calcium is variable. the risk of bone fractures .