Receptors: Signal Transduction and Phosphorylation Cascade

The video explains how cells communicate using receptors, which are proteins that receive signals from outside the cell. These signals, often in the form of ligands, bind to receptors and cause conformational changes that trigger various cellular responses. The video covers signal transduction, second messengers, relay molecules, receptor-mediated endocytosis, and intracellular receptors. It also discusses how these processes can affect gene expression, metabolism, and cell division.

What is the primary function of receptors in cell communication?

• To produce energy for the cell

• To transport nutrients across the cell membrane

• To receive and process information from outside the cell

• To store genetic information

Which molecule is known as a second messenger in signal transduction?

• Glucose

• Cyclic AMP

• DNA

• ATP

What role do G-proteins play in cell signaling?

• They transport oxygen in the blood

• They break down proteins

• They activate enzymes to produce second messengers

• They store genetic information

What is the process called when receptors cluster into a pit to absorb substances?

• Active transport

• Receptor-mediated endocytosis

• Signal transduction

• Phosphorylation cascade

How do intracellular receptors differ from membrane-bound receptors?

• They are involved in photosynthesis

• They are located on the cell surface

• They do not bind to any ligands

• They require ligands to be small and non-polar

What can happen if a signaling pathway malfunctions and fails to stop cell division?

• Improved digestion

• Enhanced immune response

• Tumor growth

• Increased energy production

What is a potential outcome when an intracellular receptor is activated?

• The cell becomes dormant

• A gene is turned on or off

• The cell membrane dissolves

• The cell changes shape