But yeah, anywhere in your 20s is still young. Early 30s is where that ends. kingkong113 said: â. I ask this because this girl in my Precal class has been all on my dick and is clearly looking to hook up but she is like 28. but she did say and I quote My Pussy is tight though lol who says that to someone.
Active transport. Active transport is the movement of molecules across a cell membrane from a region of their lower concentration to a region of their higher concentrationâin the direction against some gradient or other obstructing factor (often a concentration gradient).
Proteins in Active Gradient Transport. Active transport is transport against a concentration gradient that requires chemical energy. Active transport moves ions or molecules in a specific direction through the use of an integral membrane protein. Think of these like different gates at the fair. There are three types of membrane proteins that use energy to push these substances against the concentration gradient.