It’s just a blob of tissue!
Let’s be clear on our terms. Tissues are the component parts of an organism. An organism is a mass of tissues organized into a coherent whole. So, in a certain sense, a fetus is a mass of tissue. But so is a human adult.1 And neither a fetus nor an adult is a disorganized mass of tissue, as implied by “blob.” Fetal parts are subservient to an integral, self-actualizing whole, which is the fetus herself. Thus, the question is not whether an unborn human is a collection of tissues. We all agree that she is. The question is whether that collection of tissues constitutes a human organism. Every biologist will tell you that she does.