Signaling Lecture Flash Cards

Front 1

What are the Main Types of Signals Send in our bodies?

Back 1

1. Direct Electrical
2. Chemical Signals

Front 2

What is Direct Electrical Signaling

Back 2

Cells are connected by gap junctions, and transmit signals directly to the next cell.
Examples: Cardiac Muscle, some smooth muscles, some neurons

Front 3

What are the 3 types of Chemical Signals

Back 3

1. Neurotransmitters (fast onset, short duration)
2. Hormones (slower onset, longer duration)
3. Local Signals

Front 4

What are the 2 classes of Hormones

Back 4

1. Polypeptides (fast onset, short duration)
2. Steroids (slow onset, longer duration)

Front 5

What are the types of local signals and their definitions

Back 5

1. Paracrines- relaeased by one cell and affects on neighboring cells. (examples: prostaglandins, histamines, Kinins)
2. Autocrines- Affect the behavior of the cell that released it. (examples: Adenosine

Front 6

What are hydrophilic signals, and how do they affect target cells?

Back 6

1. Are usually polypeptide hormones.
2. They can't pass through membranes (being hydrophilic) so they attach to a receptor on cell surface and an effector changes cell behavior by activating a 2nd messenger. (fast onset short duration)

Front 7

What are hydrophobic signals, and how to they affect target cells?

Back 7

1. Usually steroid hormone
2. Pass though the member and affect the behavior by stimulating receptors in the cytosol on in the nucleus. (slow onset, long duration)

Front 8

Are hydrophilic signals synthesized on the spot or stored in vesicles?

Back 8

Stored in Vesicles

Front 9

Are hydrophobic signals synthesized on spot or stored in vesicles?

Back 9

Made on the spot

Front 10

What are the three types of receptor- effector relationships, and give example of each?

Back 10

1. Receptor is the Effector (Tyrosine Kinase)
2. Receptor are subunits of the same protein (Nicotinic Ach Receptor)
3. Receptor and Effector are separate (G-linked Proteins)

Front 11

How does a Tyrosine Kinase receptor/effector work?

Back 11

1. Receptor binds
2. Tyrosine kinase phosphorylates itself, causing it to be active
3. Activates other proteins

Front 12

What does phosphorylating a catabolic protein do to its activity?

Back 12

Increases activity

Front 13

What does phosphorylating a anabolic protein to its activity?

Back 13

Decreases activity

Front 14

How do G-linked proteins work?

Back 14

1.Receptor receives a signal
2. G-linked protein binds GTP and rleases GDP, separates from receptor protein and is active
3. binds to Effector (adenylate cyclase) and activates effector, at same time releasing alpha and beta subunits.
4. left over subunit hydrolyzes GTP to GDP and is inactivated and rebinds alpha and beta subunits

Front 15

What does cholera Toxin do?

Back 15

Inactivates GTPase activity in G proteins, so they remain active.

Front 16

What inhibits cAMP?

Back 16

Phosphodiesterase is constantly working.

Front 17

What inhibits phosphodiesterase?

Back 17

Caffeine, Theophylline

Front 18

What is the action of cAMP on phophatases?

Back 18

Inhibits them, this prolongs the effects of phosphorylating the proteins that the cAMP did.