Cortisol and other hormones release a surge of energy in the form of glucose (sugar), which the body can use to fight or flee. That rush of glucose is no problem if your body's insulin response is working correctly.
Notice that the kittensâ ears are just beginning to unfold, though their eyes remain closed. Their sense of smell, hearing, and taste are slowly starting to develop. Tweed is only three days old. After almost a week, the kittens begin to wiggle around on their own a little bit and their eyes start to open.
They will continue to open further until somewhere between two and three weeks of age, at which point they will be open completely. A kitten's ears will also open about this time, but her eyes do open first, meaning that she will begin to develop first her sense of sight during these first few weeks of life.