Cell Signaling
term used for a molecule that specifically binds to another (usually larger) molecule
ligand
definition of cytokinesis
step ending cell division by separating the cytoplasm of two daughter cells
Which steps in mitosis will still have double the amount of DNA?
Prophase and Metaphase
Four steps of mitosis
Prophase, Metaphase, Anaphase, and Telophase
Receptor that has specifically involves phosphorylation
Receptor tyrosine kinase activity
The DNA molecules are packaged into structures called ___________.
chromosomes
what would be some examples of how a process can be regulated?
Inhibiting enzymatic activity by interrupting binding sites, decreasing concentration of signaling molecules or ions needed in process, signaling to trigger apoptosis
Three steps of interphase and interphase's main goal
G1 (first gap), S (synthesis), G2 (second gap)
copying DNA in preparation for cell division
Main purpose for phosphorylation cascades
amplification of signal several times
Define apoptosis.
Process of programmed cell death that is triggered by a cell signaling pathway
What is the expected percent change in the DNA content of a typical eukaryotic cell as it progresses through the cell cycle from the start of G1 phase to the end of G2 phase?
a. -100%
b. -50%
c. +50%
d. +100%
D
description of what occurs in metaphase
All chromatids are positioned along the midline/equator of the cell.
Examples of second messengers
Calcium ions and Cyclic AMP (cAMP)
Definition of sister chromatids
joined copies of original chromosomes connected by the centromere
Binding of a signaling molecule to what type of receptor leads directly to a change in the distribution of ions on opposite sides of the membrane?
ligand gated ion channel receptor
Difference between normal cells and cancer cells
Cancer cells have no checkpoints or regulation of cell division and does not undergo apoptosis
Three steps of cell signaling
1) signal reception
2) transduction
3) cellular response
Term used for points in the cycle where stop and go ahead signals regulate the cell cycle
What are two of the regulatory proteins that are used at these points in the cell cycle by forming a complex
checkpoints
cyclin and cyclin dependent kinases
If a cell at metaphase of mitosis contains 20 sister chromatids, how many chromosomes will be present in the beginning of G1 phase?
10
When in mitosis do sister chromatids become chromosomes?
Anaphase