Cell Communication
What type of signaling occurs when cells communicate over long distances through hormones?
Endocrine Signaling
What is the purpose of signal transduction?
To convert an external signal into a cellular response.
What type of feedback maintains homeostasis by reversing changes?
Negative feedback
What are the 3 main phases of interphase?
G1,S,G2
What is cancer?
Uncontrollable cell division
What molecule binds to receptor protein?
Ligand
What second messenger is usually involved in signaling pathways?
cAMP
Which feedback increases or amplifies a change?
Positive feedback
During which phase is DNA replicated?
What type of genes stop the cell cycle, if problems occur?
Tumor supressor genes
Why can steroid hormones pass through the cell membrane?
They are nonpolar lipids.
Protein kinases transfer what group to proteins?
Phosphate groups
One example of positive feedback in the human body?
Contractions, Blood clotting
What's the purpose of checkpoints in the cell cycle?
To ensure the cell is ready to proceed
What protein helps regulate the cell cycle and can trigger apoptosis?
p53
What type of receptor is usually used for water signaling molecules?
Cell Surface Receptors
What happens during phosphorylation?
The phosphate group is added
Why is negative feedback important?
During which phase do sister chromatids separate?
Anaphase
What is apoptosis?
Programmed cell death
The term for communication for nearby cells using local regulators?
Paracrine Signaling
Why are the signaling cascades good for cells?
They amplify the signal and create a bigger response
What happens if cells lose the ability to respond to regulatory signals?
Uncontrolled cell growth
Which structure pulls chromosomes apart during mitosis?
Spindle Fibers
How can mutations in proto-oncogenes contribute to cancer?
They can become oncogenes that cause excessive cell division