Ch.6 Study Guide: Communication, Integration & Homeostasis

Question 1

Endocrine gland

Answer 1

A Gland that produces endocrine secretions hormones into the blood example thyroid or pituitary gland

Question 2

Hormone

Answer 2

Produced by endocrine glands. Chemical substance that act As messenger molecules in the body made in one part of the body and travel to another part where they help control how cells and organs do their work. Example estrogen glucagon insulin

Question 3

Cytokine

Answer 3

Signaling molecule that aid cell to cell communication in immune response and trauma. released by white blood cells through the process of diffusion both locally and long distance examples lymphocyte, macro phage, granulocyte, mast cells

Question 4

Neurotransmitter

Answer 4

Signaling molecules are created by neuron to affect another cell across a synapses. Can be any main body part, target sell, another neuron, gland, or muscle

Question 5

Neurohormone

Answer 5

Hormone that stimulates the nervous system. Produced by neuroendocrine cells, involved in systemic effect; autocrine, paracrine messenger example oxytocin and ADH

Question 6

Paracrine signal

Answer 6

Type of diffusion, cell targets a cell nearby (local communication) example histamine

Question 7

Autocrine signal

Answer 7

Type of diffusion that targets self, releasing a signal that can bind to receptors on its own surface (local communication)

Question 8

Lipophilic

Answer 8

Ability to dissolve in fats and lipids. Can easily pass plasma membrane hydrophobic bind to the receptors inside the cell. Rare and slow

Question 9

Lipo phobic

Answer 9

Molecules that are water soluble and do not readily cross plasma membrane.  find the receptor proteins on cell membrane (common and fast)

Question 10

Signal transduction

Answer 10

Process of a signal transmitted to cell intracellular fluid to extracellular fluid to enact a response.

Signal >receptor >transducer >amplifier >response

Question 11

Target cell

Answer 11

Information brought to from signal molecule

Question 12

Receptor

Answer 12

Where ligand (1st messenger)bonds to activate the inter-cellular signal molecules.

Question 13

Transducer

Answer 13

 convert the message of extra cellular signals into intracellular messenger molecules that trigger a response

Question 14

First messenger

Answer 14

Original signal ligand

Question 15

Second messenger

Answer 15

Produced by an amplifier enzyme product of response from first messenger

Question 16

Amplifier enzyme

Answer 16

Turned on by receptor ligand complex, activates several molecules, turns on several more as cascade proceeds

Question 17

Amplification

Answer 17

Turns one signal molecules into multiple second messenger Molecules

Question 18

Protein kinase

Answer 18

Phosphorylates a protein. Important intracellular enzyme that plays a crucial role in most signal transduction Cascades. Catalyzing transfer of phosphate between their substrates

Question 19

ProTien phosphatase

Answer 19

Opposite of protein kinase, removes a phosphate group from a proTien

Question 20

Agonists

Answer 20

Binds to the receptor producing a response

Question 21

Antagonist

Answer 21

Has affinity but does not produce response when blinded to the target receptor

Question 22

List and describe the two general groups of signal types which is most common in the body?

Answer 22

Electrical signals from neurons and chemical signals from hormones (more common)

Question 23

List and describe the three methods of local communication. Explain the difference between paracrine and autocrine signals, the method of communication and provide examples of each

Answer 23

1. Gap Junction direct link between cells example intercalated discs in heart
2. Contact dependent signals (cams)
3. Diffusion: Paracrine, next to each other and autocrine, same cell ex:histamine

Question 24

Describe how long distance communication is achieved and which organ systems are typically involved with it provide an example of long-distance communication that utilizes the dual signaling methods. Explain the difference between neurotransmitters hormones and neurohormones

Answer 24

Usually a combo of electrical and chemical reactions the nervous system and endocrine system are the two major organ systems. Endocrine system uses hormones for chemical signals and the nervous system uses both chemical and electrical to communicate.

Chemical signals are secreted by neurons chemical diffusers from the neuron to the saw where it is called a neurotransmitter when it diffuses into the blood it becomes a neurohormone

Question 25

Compare intracellular and membrane receptors, including the types of ligands that may be utilized for each, how the signal is transmitted from outside the cell to the inside and the typical response time for each

Answer 25

Intracellular : (rare) ligand needs to cross the cell membrane lipophilic nonpolar slow response minutes to hours example is the start of Gene transcription.
Extracellular membrane receptor: common receptor outside of Cell polar Lipo phobic cannot cross cell membrane. * process is called signal transduction and response time is fast milliseconds

Question 26

List the components of a general signal transduction pathway and use it as a model to illustrate a simple example explain the relationship between first messenger and it’s response

Answer 26

Signal(1st messenger)>receptor >transducer >amplifier >response (2nd messenger) . External signal binds to specific receptor to elicit a response intracellularly.

• need to practice on whiteboard.

Question 27

Let’s the four major categories of receptor types and their general actions

Answer 27

1) Receptor channels: Ligand gated channels ion channel receptor (ICR) gate opens and closes when ligand binds to receptors.
2) Receptor enzyme complex: ligand activate the enzyme after binding to receptor
3) ?intergin receptor: Ligand activates intracellular response example blood clotting movement of cytoskeleton
4) G protein coupled receptors (gpcr) : Open and closes ion channel that starts a cascade of reactions inside the cell

Question 28

Explain the concept of Cascades and amplification in signal transduction in both simple terminology and he’s in precise terminology

Answer 28

Cascade: chain reaction of events that lead to a response. **

Amplification: I swim use of amplification enzyme amplification goes up with the number of enzymes that it stops at in a cascade. Amplification enzymes produce a second messenger.

Question 29

A list and describe the three general actions of second messengers provided and lecture what role did protein kinase and protein phosphatase have an signal transduction pathways

Answer 29

1. open or close ion channels creating an electrical signal
2. Increase intracellular calcium ions which bind to Pro Tien changing its shape/function
3. Activates protein kinase or pro Tien phosphatase.

Protein kinase transfers a phosphate to activate cellular change.

Protein phosphatase removes phosphate and stops signal transduction pathway.

Question 30

Describe the structure, activation, actions and affects of ligand gated receptor channels. List other types of ion channels such as voltage gated channels. What are the transmission and response time characteristics of receptor channels.

Answer 30

Activated by ligand that opens and closes the channel for ion passage sodium and potassium. Ligand gated channels seen in neurons and muscle cells and may be linked to GPCR. Some may be activated by changing voltage voltage gated or in change in pressure mechanically gated or ATP gated very fast response time.

Question 31

Describe the structure, activation, actions and effects of receptor enzyme complexes. Describe in particular tyrosine kinase and guanylyl cyclase receptor enzyme complexes

Answer 31

** white board and paper flash card**

Question 32

Describe the structure activation and actions/effects of G protein coupled receptors. What is the role of GDP and GTP? Described in particular the GPCR adenylyl cyclase CAMP and phospholipase C systems and provide examples of each

Answer 32

* white board and paper flash card

Question 33

Explain how signal pathways maybe modulated through saturation, specificity, competition, and up and down regulation. Provide examples or scenarios for each factor.

Answer 33

Saturation: it bindings I can only handle so many interactions with wagons in a given period of time. Specificity: one receptor has one specific like and it interacts with. Competition: agonist and antagonist Competing ligands with similar structures to primary ligand can bind to receptor. Up and down regulation: cells can control the amount of response by increasing or decreasing the number of receptors available. Persistent drug use may cause down regulation and desensitization

Question 34

How did drugs/diseases affect the pathway of signal transduction

Answer 34

Many Pharma logical drugs and diseases target and different aspects of signal transduction pathways example receptors G proteins second messengers. Beta blockers and calcium channel blocker‘s treat high blood pressure histamine type to receptor antagonist decrease stomach acid secretion.