Cell Communication
Vocabulary: signal transduction pathway, quorum sensing, hormones, protein kinase, protein phosphatase, G proteins, cyclic AMP, first messengers, second messengers, signal amplification, apoptosis, paracrine signaling, synaptic signaling, hormonal signaling
1. Know the three stages of Cell Signaling:
a. Reception - receptors in the plasma membrane, intracellular receptors
b. Transduction - signal transduction pathways, phosphorylation and dephosporylation, second messengers
c. Response - nuclear and cytoplasmic responses; protein synthesis, ion channels, cell shape
2. Describe the relationship between signal molecules and cell surface receptors, and give examples of each.
3. Describe G-protein-linked receptors and receptor tyrosine kinases, and explain the role of each in receiving chemical signals and initiating signal transduction pathways.
4. Describe a signal transduction pathway and explain how this multi-step process can amplify the signal and lead to a cellular response.
5. Understand that different kinds of cells have different collections of proteins (p.221) and how this affects the response of a particular cell to a specific signaling molecule.
6. Define apoptosis and describe its importance and function(s) in an organism.
| 6014592045 | amplification | The strengthening of stimulus energy during transduction. |  | 0 |
| 6014592047 | cytoplasm | The contents of the cell, exclusive of the nucleus and bounded by the plasma membrane. | 1 | |
| 6014592049 | G protein | A GTP-binding protein that relays signals from a plasma membrane signal receptor, known as a G protein-coupled receptor, to other signal transduction proteins inside the cell. |  | 2 |
| 6014592052 | ligand | A molecule that binds specifically to another molecule; often first step in cell communication. Water soluble ligands typically do not enter cell. Lipid soluble ligands (such as steroids) do enter the cell. | 3 | |
| 6014592053 | ligand-gated ion channel | A protein pore in cellular membranes that opens or closes in response to A signaling chemical (its ligand), allowing or blocking the flow of specific ions. |  | 4 |
| 6014592055 | protein kinase | An enzyme that transfers phosphate groups from ATP to a protein, thus phosphorylating the protein. | 5 | |
| 6014592056 | protein phosphatase | An enzyme that removes phosphate groups from (dephosphorylates) proteins, often functioning to reverse the effect of a protein kinase. | 6 | |
| 6014592059 | second messenger | A small, nonprotein, water-soluble molecule or ion, such as a calcium ion (Ca2+) or cyclic AMP, that relays a signal to a cell's interior in response to a signaling molecule bound by a signal receptor protein. | 7 | |
| 6014592060 | signal transduction | The linkage of a mechanical, chemical, or electromagnetic stimulus to a specific cellular response. | 8 | |
| 6014592061 | signal transduction pathway | A series of steps linking a mechanical or chemical stimulus to a specific cellular response. There are four types that we studied: g-protein linked reception; hormonal reception; receptor tyrosine kinase reception; pathways using second messengers (cAMP; calcium ions). | 9 | |
| 6014592064 | three stages of cell communication | reception - receptor responds to binding of ligand molecule; transduction - translation and amplification of message; response - activation of cellular response |  | 10 |
| 6014592065 | g-linked protein receptor | receives message for g-linked protein signaling pathway. Consists of seven alpha helices that span the plasma membrane. Changes shape when ligand molecule binds. |  | 11 |
| 6014592066 | signal transduction pathway | The process by which a signal on a cell's surface is converted into a specific cellular response. |  | 12 |
| 6014592067 | local regulators | These regulators influence cells in the vicinity of them. |  | 13 |
| 6014592068 | hormones | Circulating chemical signals that are formed in specialized cells, travel in body fluids, and act on specific target cells. Attaches to receptor proteins in the cell's cytoplasm. |  | 14 |
| 6014592071 | protein phosphatases | Enzymes that can rapidly remove phosphate groups from proteins. |  | 15 |
| 6014592072 | second messengers | Small, non-protein water soluble molecules or ions that send messages throughout the cells by diffusion. |  | 16 |
| 6014592073 | reception | The target cell's detection of a signal molecule coming from outside the cell. |  | 17 |
| 6014592074 | transduction | The binding of the signal molecule changes the receptor protein in some way. |  | 18 |
| 6014592075 | response | The transduced signal finally triggers a specific cellular response. |  | 19 |
| 6014592076 | G-protein-linked receptor | A plasma membrane receptor that works with the help of a G-protein. |  | 20 |
