Lecture Review Flashcards

Flashcards from lecture notes.

Cell Adhesion Molecules (CAMs)

Act as receptors within cell-to-cell signaling.

Autocrine

Signaling where a cell targets itself.

Long Distance Communication

Communication using endocrine signals (hormones) or neurohormones (through the nervous system).

Hormones

Chemical signals that travel through the blood and disperse throughout the body.

Nervous System Communication

Rapid and specific due to neurotransmitters; effects tend to be shorter-lived.

Endocrine System Communication

Can be specific, but slower than the nervous system; effects tend to last longer because hormones are usually proteins.

Neurocrines

Include neurotransmitters, neuromodulators, and neurohormones.

Cytokines

Chemical messengers involved in various cell signaling pathways; include interferons and interleukins.

Erythropoietin (EPO)

A hormone that triggers red blood cell production; also acts as a cytokine.

Lipophilic Signals

Can pass directly through the phospholipid membrane and bind to intracellular receptors, leading to a slower response.

Lipophobic Signals

Bind to receptors on the cell surface because they cannot diffuse through the membrane, leading to a faster response.

Signal Transduction Pathway Responses

Include triggering enzymes, controlling gene activity and protein synthesis, affecting transport, and affecting proteins.

G Coupled Proteins

A huge group of protein receptors that bind various ligands like hormones and growth factors.

Ligand Gated Ion Channels

Simplest receptors; neurotransmitters are a good example.

Nitric Oxide (NO)

In small amounts, can help smooth muscle and cause vasodilation; in large amounts, can be damaging.

Prostanoids

Resemble prostaglandins and affect sleep.

Agonist

A molecule that turns on a receptor.

Antagonist

A molecule that blocks a receptor.

Down Regulation

Decreasing the number of receptors through exocytosis.

Desensitization

Change in receptor response, leading to drug tolerance.

Up Regulation

Adding more receptors through exocytosis.

Termination

Breaking down neurotransmitters with enzymes, e.g., acetylcholinesterase for acetylcholine.

Rhodopsin

A protein in rods that helps us see in dim light.

Epinephrine

Can either vasoconstrict or vasodilate blood vessels (BV), depending on the receptor.

Stimulus

Triggers depolarization in excitable tissues.

Excitable Tissues

Muscles and nervous tissue that can conduct an electrical current.

Membrane Potential Influences

Concentration gradient of ions and membrane permeability.

Graded Potentials

Not as strong as action potentials, but can be added together to trigger an action potential if threshold is reached.