No.
There's a commonality between the examples you gave, namely they are both eggs. For most animal life, the largest cell is the egg-cell, this is true for humans as well. The human ovum is around 0.12mm in diameter.
The largest uni-cellular life gets to around 4-9 cm, slightly larger than a chicken egg. The largest single celled organism (Caulerpa taxifolia) actually looks a lot different than most macroscopic uni-cellular life.
It can only get so big because it has a unique structure that increases surface area, this life form also has multiple nuclei, so it's a bit of cheat. They don't get larger than 30cm high.
When a uni-cellular circular organism gets larger*, its membrane surface area increases by $4\pi(\Delta r)^2$ whereas its volume increases by $\frac{4}{3}(\Delta r)^3$, where $\Delta r$ is the increase in radius. In other words, the interior grows faster than the membrane.
Cells need a large enough surface area in order for food and waste to move in and out. Large cells also require thicker membranes, making this transport of food and waste more difficult. The result is that most uni-cellular life remains microscopic, and none can get as large as you want.
*Of course uni-cellular life isn't exactly circular, but this is for easier calculation.