EXCAVATOR are heavy construction equipment consisting of a boom, stick, bucket and cab on a rotating platform (known as the house). The house sits atop an undercarriage with â¦ tracks or wheels. A cable-operated excavator uses winches and steel ropes to accomplish the movements.
First Trimester (0 to 13 Weeks). The first trimester is the most crucial to your baby's development. During this period, your baby's body structure and organ systems develop. Most miscarriages and birth defects occur during this period. Your body also undergoes major changes during the first trimester. These changes often cause a variety of symptoms, including nausea, fatigue, breast tenderness and frequent urination. Although these are common pregnancy symptoms, every woman has a different experience.
The 40 weeks of an average pregnancy are usually discussed in terms of three trimesters, each approximately 13 weeks. During the second and third trimesters, the pre-pregnancy uterusâabout the size of a fistâgrows dramatically to contain the fetus, causing a number of anatomical changes in the mother (Figure 1).