week 12 communication & signaling Flashcards
Principles of Cells Signaling
receive from the environment
exchange with other cells
short or long range
can be intracellular
Signalling mechanisms
Aucotrine
Gap Junction/ Juxtacrine/ Contact
Neuronal
Paracrine
Endocrine
Autocrine
Cell signalling to itself
Gap Junction/ Juxtacrine/ Contact
Protein permit direct cell-cell contact
Adjacent cell communication via membrane bound signal
Neuronal
Neurotransmitter released from the nerve
Paracrine
mediators released within the local area
Endocrine
Hormones released (secreted) and distributed through the blood stream
Ligands
Bind to the receptor
chemical molecules, hydrophobic or hydrophilic
Receptors
proteins with specific binding sites (to particular ligands).
Intracellular - steroid
cell surface - ion, g-protein, enzyme-linked, non-enzyme containing receptors
Transduction
Receptor often generates a second messenger response to amplify signal
Endocrine Glands
Pituitary Gland - Growth Hormone
Thyroid- energy temp metabolism
Parathyroid - Calcium phosphorus and magnesium
Adrenal - metabolism, immune, blood pressure
Gonads - Reproduction
Placenta - nutrients and oxygen to baby
Endocrine Organs
Brain
Heart
Liver
Gastrointestinal Tract
Kidneys
Fat
Hormone
Class of signaling molecules
some in extracellular substance
hormones induce specific responses in target cells
Travel through blood stream
Protein & Peptide Hormones
Synthesised from amino acids as peptides
Steroid Hormones
Derived from cholestorol or fatty acids
