Exploring Cell Transport Concepts

The video tutorial covers cell transport, focusing on how substances move in and out of cells to maintain homeostasis. It explains dynamic equilibrium and feedback mechanisms, both positive and negative. The cell membrane's role in selective permeability is discussed, along with passive transport methods like diffusion and osmosis, and active transport methods such as molecular pumps and vesicle transport.

What is homeostasis?

• The production of energy within a cell

• The maintenance of stable internal conditions in an organism

• The movement of substances across a cell membrane

• The process of cell division

What is a stimulus?

• A change in the environment that elicits a response

• A response to an environmental change

• A type of passive transport

• An equilibrium state in the cell

What does a positive feedback loop result in?

• No change in the system

• Intensifying the response

• Stabilizing the system

• Decreasing the response

What characterizes a negative feedback loop?

• It stabilizes a system by reversing changes

• It only occurs in non-living systems

• It amplifies changes

• It has no effect on the system

What can easily pass through the cell membrane?

• Only ions

• Only proteins

• Small nonpolar molecules

• Large polar molecules

What is the main function of the cell membrane in homeostasis?

• To divide the cell during mitosis

• To control what enters and exits the cell

• To produce energy

• To store genetic information

What is facilitated diffusion?

• Movement of water molecules only

• Transport of molecules without a protein channel

• Transport of molecules with the help of a protein channel

• Transport requiring energy

What is osmosis?

• The use of energy to move molecules

• The movement of solutes from low to high concentration

• The diffusion of water across a cell membrane

• The active transport of ions

What is the role of molecular pumps in active transport?

• To produce ATP

• To assist in passive transport

• To move molecules against a concentration gradient using energy

• To facilitate the diffusion of water

What is required for active transport?

• No energy

• ATP or energy

• Only water molecules

• A concentration gradient