Question

read the paragraph.
despite its name, the pacific sea horse is actually a type of fish. its horse - shaped head gives it its name. this creature lives in the pacific waters off the west coast of the americas, from peru to southern california. like many other ocean fish, sea horses face the constant challenge of losing water to their saltier environment.
when a pacific sea horse’s body loses water to its environment, which process is responsible?

• exocytosis
• endocytosis
• osmosis
• active transport

Explanation:

To determine the process responsible for a Pacific sea horse losing water to its saltier environment, we analyze each option:

• Exocytosis: Involves releasing substances from a cell, not water loss due to concentration differences. Eliminate.
• Endocytosis: Involves taking substances into a cell, not water loss. Eliminate.
• Osmosis: Is the movement of water across a semipermeable membrane from an area of lower solute concentration (higher water concentration) to higher solute concentration (lower water concentration). Since the sea horse's body has a lower solute concentration than the saltier environment, water moves out via osmosis.
• Active transport: Requires energy to move substances against a concentration gradient, not relevant for passive water loss here. Eliminate.

Answer:

C. osmosis