Final answer:
The fundus, the top portion of the uterus, becomes palpable at about 12 to 14 weeks of pregnancy.
Step-by-step explanation:
The fundus is the top portion of the uterus, and its ability to be palpable (felt through the abdomen) is an important marker in pregnancy. The fundus is typically first palpable at around 12 to 14 weeks of pregnancy. At this stage, it can generally be felt just above the pubic bone. As the pregnancy progresses, the fundus continues to grow and can be palpated progressively higher in the abdomen, serving as a measure of fetal growth and uterine size.