Through which type of transport do large molecules such as starch cross the call membrane against the concentration gradient? BELECT ALL THAT APPLY a endocytosis b exocytosis c facilliated diffusion d diffusion

## Step 1<br />The problem is asking about the methods through which large molecules, such as starch, can cross the cell membrane against the concentration gradient. This means that the molecules are moving from an area of lower concentration to an area of higher concentration, which is against the natural flow of substances.<br /><br />## Step 2<br />The options provided are endocytosis, exocytosis, facilitated diffusion, and diffusion. <br /><br />## Step 3<br />Endocytosis and exocytosis are processes that involve the movement of large molecules across the cell membrane. In endocytosis, the cell membrane engulfs the large molecule, effectively bringing it into the cell. In exocytosis, the cell membrane expels large molecules out of the cell.<br /><br />## Step 4<br />Facilitated diffusion and diffusion, on the other hand, are passive transport mechanisms that do not require energy. They move substances from an area of high concentration to an area of low concentration, which is the natural flow of substances. Therefore, they cannot be used to transport large molecules against the concentration gradient.