Review (HAP) Unit 1 Concept 2 - Homeostasis & Regulation

What is homeostasis?

• The breakdown of glucose for energy
• The maintenance of stable internal conditions
• The movement of substances across cell membranes
• The process of cell division

Which of the following best describes a receptor?

• An enzyme that catalyzes reactions
• A molecule that receives and responds to specific signals
• A protein that breaks down substances
• A structure that stores genetic material

What is a stimulus in the context of cell biology?

• A cellular waste product
• A change in the environment that triggers a response
• A type of protein synthesis
• The process of DNA replication

An effector is best described as:

• A chemical messenger
• A substance that triggers a response
• A structure or organ that carries out a response
• A type of receptor molecule

What is feedback inhibition?

• The breakdown of proteins
• The buildup of waste products
• A process that speeds up cellular reactions
• A mechanism that stops a pathway when products accumulate

Passive transport is characterized by:

• Active protein carriers
• Movement against a concentration gradient
• Movement with a concentration gradient without energy
• The use of ATP energy

Which solution has a higher solute concentration than the cell?

• Hypotonic solution
• Hypertonic solution
• Isotonic solution
• Pure water

What is a ligand?

• A cellular waste product
• A type of cell membrane
• A molecule that binds specifically to a receptor
• An energy storage molecule

The signal transduction pathway:

• Converts external signals to internal cellular responses
• Is the same in all cell types
• Only occurs in plant cells
• Requires no energy

An inhibitor in cell signaling:

• Blocks or reduces signal transmission
• Enhances membrane transport
• Increases protein production
• Speeds up cellular reactions