Cell Communication
The name of the molecule that is the signal to a cell.
What is a ligand?
A signal pathway that requires the passing of phosphates from one molecule to another.
What is a phosphorylation cascade?
Phase where cell grows.
What is G1 phase?
The name of two copied chromosomes that are attached at the centromere.
What are sister chromatids?
The type of feedback that causes the stimulus to decrease or reverse.
What is negative feedback?
What is a receptor?
A type of protein that transmits the signal from the receptor to the inside of the cell by acting as a molecular switch, being turned on or off by binding to the activated receptor and replacing GDP with GTP.
What are G-proteins?
What is S (Synthesis) phase?
The phase where the spindle attaches to the centromere of the chromosomes and the chromosomes line up.
What is metaphase?
Type of feedback that causes the stimulus to increase.
What is positive feedback?
A cell signal that travels through the bloodstream to reach target cells throughout the body.
What is an endocrine hormone?
A membrane receptor that forms a "dimer receptor" and steals phosphate groups from ATP.
What is tyrosine kinase?
The first three phases, G1, S, and G2 are collectively called this.
What is interphase?
Checkpoint that occurs before the cell begins mitosis to determine if there are any mistakes in the DNA and the cell is ready to divide.
What is the G2 checkpoint?
Genes that produce proteins that prevent the cell from undergoing mitosis.
What are tumor suppressor genes?
A cell signal that can also signal itself.
What is autocrine?
Type of ligand that can pass through the membrane and act directly on cell activities.
What is a lipid hormone (steroid)?
Phase in which the cell stops proceeding through the cell cycle. Many of these cells never divide again.
What is the G0 phase?
The phase in which the nuclear envelope is rebuilt around the two new nuclei.
What is telophase?
The levels of these molecules rise and fall with each phase of the cell cycle to signal the cell to continue on to the next phase.
What are cyclins?
Plasmodesmata allows ligands to move directly between plant cells and is an example of this type of cell communication.
What is juxtracrine?
This molecule is considered a second messenger because it takes the message from the original ligand bound receptor molecule and amplifies the signal within a cell.
What is cAMP or cyclic AMP?
If a cell is damaged, p53 produces a protein that causes a cell to undergo this process.
What is apoptosis or programmed cell death?
An animal cell pinches off the cytoplasm during cytokinesis but a plant cell builds this structure.
What is a cell plate?
The binding of these two molecules is what provides the signal for the cell to continue with mitosis.
What are cylins and CDK's (cylin dependent kinases)?