Question

hormones are proteins that regulate growth, metabolism, development, and reproduction in organisms.
image: diagram showing glucose, insulin, insulin receptor, glucose channel (open) on a cell
like other proteins, the shape of a hormone is critical for its function. for example, insulin is a hormone that helps regulate blood sugar, or glucose levels. when glucose levels increase, cells in the pancreas release insulin. insulin binds specifically to receptors on the outside of cells in the liver and other parts of the body. this causes those cells to take in glucose, which lowers blood sugar levels.
select the true statement.
hormones speed up chemical reactions.
insulin’s shape allows it to bind to specific parts of a cell.
insulin transports glucose into a cell.

Explanation:

• For "Hormones speed up chemical reactions": Enzymes (not hormones) are proteins that speed up chemical reactions. Hormones regulate processes like growth, metabolism, etc., so this is false.
• For "Insulin's shape allows it to bind to specific parts of a cell": The text says "the shape of a hormone is critical for its function" and "Insulin binds specifically to receptors on the outside of cells...". Receptors are specific parts of cells, so insulin's shape enables this specific binding. This is true.
• For "Insulin transports glucose into a cell": The text says insulin binding to receptors causes cells to take in glucose (via the glucose channel), but insulin itself doesn't transport glucose. The glucose channel does the transport, so this is false.

Answer:

Insulin's shape allows it to bind to specific parts of a cell.