Guide Questions: Q30. How long does a regular menstrual cycle last? Q31. Describe what happens to an egg during the first 14 days of the cycle in Part A. Q32. Describe what happens to the egg if fertilization occurs. Q33. Explain what takes place in the uterus after fertilization. Q34. Why is it important to study the menstrual cycle Q35. What might happen to a person whose nervous and endocrine systems fail to maintain homeostasis? Q36. Suppose a boy skipped his lunch for the day. How will the hormones (glucagon) from his pancreas help his body to cope when his blood sugar level drops below normal? Q37. Suppose a girl ate too many sweets such as candies and chocolates. How will the hormones (insulin) from her pancreas help her body cope with a possible blood sugar level rise above normal? Q38. How do the nervous and endocrine systems respond to an increase in environmental temperature to achieve homeostasis? Q39. How do the nervous, endocrine, and reproductive systems perform their coordinated functions in various functions such as pregnancy and childbirth, menstrual cycle, breastfeeding, and sexual intercourse?