Your baby's growing steadily, having gained about 4 ounces since last week. That puts him at just over a pound. Since he's almost a foot long he cuts a pretty lean figure at this point, but his body is filling out proportionally and he'll soon start to plump up. His brain is also growing quickly now, and his taste buds are continuing to develop. His lungs are developing "branches" of the respiratory "tree" as well as cells that produce surfactant, a substance that will help his air sacs inflate once he hits the outside world. His skin is still thin and translucent, but that will start to change soon.