Unit 4 - Cell Communication and Cell Cycle

Gap junctions

________ in animals and plasmodesmata in plants are tiny channels that directly connect to neighboring cells, which allow the cells to transfer signaling molecules that transmit their current state of homeostasis with one another.

signal transduction

When a ligand binds to a receptor on a cell, the cell relays the message through a series of reactions to elicit a cellular response-** ________ pathway.

cellular response

Starts a signaling cascade that can amplify the signal through a series of reactions that leads to a(n) ________, resulting in a change to a cells behavior or characteristics.

Endocrine

________ signaling**/*/* involves cells far apart in which a longer- lasting signal, called a hormone, is released into the extracellular fluid and travels widely throughout the organisms to target cells.

Ca2+

Some proteins have binding sites for ________ and when calcium binds to the protein, the shape changes, leading to a change in function.

Survival

________ depends on receiving and processing information from outside the cell- information about changing environmental conditionals, availability of nutrients, or any other information vital to ________.

Paracrine signals

________ can diffuse only over relatively short distances.

Calcium

________ (Ca2+): ________- widely used by cells as a secondary messenger.

Cyclic AMP

________ (cAMP): Cyclic adenosine monophosphate (cAMP)- involved in many signal cascade pathways.

Cell

________ signaling involves: ligand, a signaling molecule, a receptor protein to which the ligand binds.

Protein hormones

________ are large molecules that must bind to receptors on the cell membrane.

signal transduction

The ________ pathway- requires activating or inactivating proteins- via the addition of a phosphate group-** phosphorylation**