Chapter 6 Vocab Flashcards
a form of adenosine monophosphate in which the phosphate is part of a ring-shaped structure; acts as a regulatory molecule and second messenger in organisms ranging from bacteria to humans
Cyclic Adenosine Monophosphate (cAMP)
mechanisms of communication between cells. Cells signal one another with secreted signaling molecules, or a signaling molecule on one cell combines with a receptor on another cell
Cell Signaling
a cell or tissue with receptors that bind a hormone
Target Cells
a cell must synthesize and release signaling molecules
Signal Transmission
process of receiving an incoming signal
Reception
large proteins or glycoproteins that bind with signaling molecules
Receptors
the process by which a cell converts an extracellular signal into an intracellular signal that causes a response
Signal Transduction
chemical signals used by neurons to transmit impulses across a synapse
Neurotransmitters
a chemical messenger, often produced in one region of the body of a multicellular organism and transported to another region where it signals cells to alter some aspect of growth, development, or metabolism
Hormones
a gland that secretes hormones directly into the blood or tissue fluid instead of into ducts
Endocrine Glands
prostaglandins (a group of local hormones), growth factors, cytokinesis, and other soluble molecules that act on nearby cells by paracrine regulation or act on the cells that produce them
Local Regulator
the fluid that bathes the tissues of the body
Interstitial Fluid
a type of regulation in which a signal molecule diffuses through interstitial fluid and cats on nearby target cells
Paracrine Regulation
substance released from mast cells that causes inflammation
Histamine
a gaseous signaling molecule; a neurotransmitter
Nitric Oxide (NO)
a group of local regulators derived from fatty acids; synthesized by most cells of the body and produce a wide variety of effects
Prostaglandins
a molecule that binds to a specific site in a receptor or other protein
Ligand
visual purple; a light-sensitive pigment found in the rod cells of the vertebrate eye; a similar molecule is employed by certain bacteria in the capture of light energy to make ATP
Rhodopsin
a blue-green, proteinaceous pigment involved in a wide variety of physiological responses to light
Phytochrome
a proteinaceous pigment that strongly absorbs blue light; implicated in resetting the biological clock in plants, fruit flies, and mice
Chryptochrome
some hormones receptors decrease in number
Receptor Down-Regulation
some hormone receptors increase in number
Receptor Up-Regulation
convert chemical signals into electrical signals; in the plasma membrane
Ion Channel-Linked Receptors
the ion channel opens or closes in response to the binding of the signaling molecule
Ligand-Gated Channels
a common neurotransmitter released by cholinergic neurons, including motor neurons
Acetylcholine
cell surface receptors that activate a G protein in response to binding by a signaling molecule
G Protein-Linked Receptors
one of a group of proteins that bind GTP and are involved in the transfer of signals across the plasma memebrane
G Protein
transmembrane proteins with a hormone-binding site outside the cell and an enzyme site inside the cell
Enzyme-Linked Receptors
an enzyme that phosphorylates the tyrosine parts of proteins
Tyrosine Kinase
the introduction of a phosphate group into an organic molecule
Phosphorylation
one of a group of steroids that function as plant hormones and are involved in several aspects of growth and development
Brassinosteroids (BRs)
a gaseous plant hormone involved in various aspects of plant growth and development
Ethylene
proteins that regulate the expression of specific genes
Transcription Factors
an enzyme that catalyzes the removal of a phosphate group by hydrolysis
Phosphatase
a neurotransmitter that has an inhibitory effect
Gamma-Aminobutyric Acid (GABA)
a molecule similar to ADP but containing the base guanine
Guanosine Diphosphate (GDP)
like ATP but containing guanine; functions in energy transactions
Guanosine Triphosphate (GTP)
a signaling molecule that binds to a receptor on the cell surface, initiation a signal transduction process that leads to the formation of a second messenger
First Messenger
ions or small molecules that relay signals inside the cell
Second Messenger
enzyme responsible for catalyzing the conversion of ATP to cylclic AMP
Adenylyl Cyclase
an enzyme that converts cAMP to AMP
Phosphodiesterase
a substance on which an enzyme acts; a reactant in an enzymatically catalyzed reaction
Substrates
acts as second messengers
Inositol Trisphosphate (IP3) and Diacylglycerol (DAG)
a calcium-binding protein; when bound, it alters the activity of certain enzymes or transport proteins
Calmodulin
organize groups of intracellular signaling molecules into signaling complexes
Scaffold Proteins
transmembrane proteins that connect the cell to the extracellular matrix, transduce signals in 2 directions
Integrins
a group of small G proteins, named by their discovery in rat sarcoma cancer cells; important in may signaling pathways
Ras Proteins
the process by which a few signaling molecules can elicit major responses in the cell; the strength of each signaling molecule is magnified
Signal Amplification
