Identify the trimester when each fetal development finding occurs. Fetus has a heartbeat: Brain develops most rapidly during this time: Gender can be determined: Fetus can hear and respond to external stimuli: Formation of fingers, toes, and facial features: Increase in body fat reserves: 1st Trimester (Conception-13 weeks) 2nd Trimester (14-26 weeks) 3rd Trimester (27-40 weeks)

Fetus has a heartbeat: 1st Trimester (Conception-13 weeks). Brain develops most rapidly during this time: 1st Trimester (Conception-13 weeks). Gender can be determined: 2nd Trimester (14-26 weeks). Fetus can hear and respond to external stimuli: 2nd Trimester (14-26 weeks). Formation of fingers, toes, and facial features: 1st Trimester (Conception-13 weeks). Increase in body fat reserves: 3rd Trimester (27-40 weeks).