CAMPBELL BIOLOGY CHAPTER 11 EXAM QUESTIONS AND ANSWERS

CAMPBELL BIOLOGY CHAPTER 11 EXAM QUESTIONS AND ANSWERS signal transduction pathway - answer- the process by which a signal on a cell's surface is converted into a specific cellular response biofilm - answer- A microbial community that usually forms as a slimy layer on a surface local regulators - answer- Messenger molecules secreted by the signaling cell which only travel short distance and influence cells in the local vicinity growth factor - answer- one of a group of external regulatory proteins that stimulate the growth and division of cells paracrine signaling - answer- a type of local signaling where the target cell is close to the signal-releasing cell synaptic signaling - answer- a type of local signaling specific to neurotransmitters in nerve cells hormones - answer- chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another long-distance signaling - answer- cell is secreting a hormone and the hormone must travel through the blood stream to reach its target place. 3 stages of cell signaling - answer- 1. reception 2. transduction 3. response Earl Sutherland - answer- 1971 Nobel Prize (In Med): discovered cAMP as a second messenger while studying effects of epinephrine on phosphorylase. reception - answer- the target cell's detection of a signal molecule coming from outside the cell transduction - answer- in cellular communication, the conversion of a signal from outside the cell to a form that can bring about a specific cellular response signal transduction pathway - answer- A series of steps linking a mechanical or chemical stimulus to a specific cellular response. relay molecule - answer- molecule in a signal transduction pathway response - answer- In cellular communication, the change in a specific cellular activity brought about by a transduced signal from outside the cell. ligand - answer- A molecule that binds specifically to a receptor site of another molecule. G-protein coupled receptor - answer- A signal receptor protein in the plasma membrane that responds to the binding of a signaling molecule by activating a G protein. G-protein - answer- 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.. receptor tyrosine kinases - answer- belong to a major class of plasma membrane receptors characterized by having enzymatic activity - attach phosphates to tyrosine's dimer - answer- a compound whose molecules are composed of two identical monomers ligand-gated ion channel - answer- a type of membrane receptor containing a region that can act as a "gate" when the receptor changes shape intracellular receptor - answer- describes a receptor that binds to its signal inside the cell, must be nonpolar (testosterone acts as transcription factor) protein kinase - answer- An enzyme that transfers phosphate groups from ATP to a protein, thus phosphorylating the protein. protein phosphatase - answer- An enzyme that removes phosphate groups from (dephosphorylates) proteins, often functioning to reverse the effect of a protein kinase. second messenger - answer- A small, nonprotein, water-soluble molecule or ion, such as calcium ion or cyclic AMP, that relays a signal to a cell's interior in response to a signal received by a signal receptor protein. cAMP - answer- is a second messenger important in many biological processes. is derived from adenosine triphosphate (ATP) and used for intracellular signal transduction in many different organisms, conveying the cAMP-dependent pathway. adenylyl cyclase - answer- An enzyme that converts ATP to cyclic AMP in response to a chemical signal. protein kinase A - answer- a serine/threonine kinase which is activated by cAMP (immediate effect) IP3 - answer- inositol triphosphate; binds to ligand-gated channels in the endoplasmic reticulum, opening them and releasing calcium into the cytosol DAG - answer