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.
| 6205885177 | amplification | The strengthening of stimulus energy during transduction. |  | 0 |
| 6205885178 | apoptosis | A program of controlled cell suicide, which is brought about by signals that trigger the activation of a cascade of suicide proteins in the cell destined to die. |  | 1 |
| 6205885179 | cytoplasm | The contents of the cell, exclusive of the nucleus and bounded by the plasma membrane. |  | 2 |
| 6205885180 | epinephrine | water soluble ligand molecule; when secreted by the adrenal medulla, mediates "fight-or-flight" responses to short-term stresses; also released by some neurons as a neurotransmitter; also known as adrenaline. |  | 3 |
| 6205885181 | 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. |  | 4 |
| 6205885182 | gap junction | A type of intercellular junction in animals that allows the passage of materials between cells. |  | 5 |
| 6205885183 | glycogen | An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch. |  | 6 |
| 6205885185 | 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. |  | 7 |
| 6205885186 | local regulator | A secreted molecule that influences cells near where it is secreted. Used in paracrine and synaptic signaling. |  | 8 |
| 6205885187 | protein kinase | An enzyme that transfers phosphate groups from ATP to a protein, thus phosphorylating the protein. |  | 9 |
| 6205885188 | protein phosphatase | An enzyme that removes phosphate groups from (dephosphorylates) proteins, often functioning to reverse the effect of a protein kinase. |  | 10 |
| 6205885191 | 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. |  | 11 |
| 6205885195 | transcription factor | A regulatory protein that binds to DNA and affects transcription of specific genes. The hormone-receptor complex becomes a transcription factor in the steroid transduction pathway. |  | 12 |
| 6205885196 | three stages of cell communication | reception - receptor responds to binding of ligand molecule; transduction - translation & amplification of message; response - activation of cellular response |  | 13 |
| 6205885197 | 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. |  | 14 |
| 6205885198 | signal transduction pathway | The process by which a signal on a cell's surface is converted into a specific cellular response. |  | 15 |
| 6205885200 | hormones | Circulating chemical signals that are formed in specialized cells, travel in body fluids, and act on specific target cells. |  | 16 |
| 6205885201 | ligand | A molecule that specifically binds to another molecule, often a larger one. |  | 17 |
| 6205885203 | protein phosphatases | Enzymes that can rapidly remove phosphate groups from proteins. | | 18 |
| 6205885204 | second messengers | Small, non-protein water soluble molecules or ions that send messages throughout the cells by diffusion. | | 19 |
| 6205885205 | reception | The target cell's detection of a signal molecule coming from outside the cell. |  | 20 |
| 6205885206 | transduction | The binding of the signal molecule changes the receptor protein in some way. |  | 21 |
| 6205885207 | response | The transduced signal finally triggers a specific cellular response. |  | 22 |
| 6205885208 | G-protein-linked receptor | A plasma membrane receptor that works with the help of a G-protein. |  | 23 |
| 6205885209 | receptor tyrosine kinase | A receptor with enzymatic activity that can trigger more than one signal transduction pathway at once; ex. growth factor binds to neighboring RTKs, they combine to become a cross-linked dimer |  | 24 |
| 6317241009 | 3 Types of Cell Signaling | Contact Dependent; Paracrine; Endocrine | 25 | |
| 6317256787 | Contact-dependent signaling | cells can communicate by cell-to-cell contact; ex. APC & Helper T cells; Plasmodesmata; Gap Junctions |  | 26 |
| 6317294414 | Paracrine signaling | cells communicate over short distances by using local regulators that target cells in the near vicinity; ex. Neurotransmitters, Quorum Sensing & Morphogens |  | 27 |
| 6317409483 | Endocrine signaling | signals released by one cell type can travel long distances to target cells of another cell type; Insuline, Growth Hormone; Thyroid Hormone |  | 28 |
