Chemical Signal Transduction - Lecture 9

Question 1

Chemical Signal Transduction Goal

Answer 1

Change overall profile of cellular protein/enzymatic activity

Question 2

Amplifiaication of lipophilic hydrophobic messengers

Answer 2

Step 3: Hormone/receptor complex can cause many mRNA to be formed
Step 5: Many proteins are formed from each mRNA

Question 3

Signal Transduction - Hydrophilic Messangers (G-proteins)

Answer 3

• G-protein associated with each receptor
• cAMP is second messenger
• Kinase phosphore lets a target and uses ATP as the phosphate donor

Question 4

Signal Amplification - Hydrophilic Messengers

Answer 4

Phosphodieterase down cAMP very rapidly (1 to 10s to 100s to 1000s)

Question 5

Signal Transduction - Hydrophilic Messenger ex. During exercise

Answer 5

1. Epinephrine
2. Increase cAMP formation
3. Activate Protein kinase A
4. Activates hormone sensitive lipase
5. Activates lipolyses and release of fatty acids to provide fuel during exercise

Question 6

Water-soluble - Chemical classes

Answer 6

Amino acids, amines, peptides

Question 7

Fat-soluble - Chemical classes

Answer 7

Steroids, thyroid hormones

Question 8

Water-soluble - Storage in secretory cell

Answer 8

Secretory vesicles

Question 9

Fat-soluble - storage in secretory cell

Answer 9

None

Question 10

Water-soluble - Mechanism of secretion

Answer 10

Exocytosis

Question 11

Fat-soluble - Mechanism of secretion

Answer 11

Diffusion

Question 12

Water-soluble - Transport in blood

Answer 12

Dissolved

Question 13

Fat-soluble - Transport in blood

Answer 13

Bound to carrier protein

Question 14

Water-soluble - Location of receptor

Answer 14

Plasma membrane

Question 15

Fat-soluble - Location of receptor

Answer 15

Cytosol or nucleus

Question 16

Water-soluble - signal transduction mechanism

Answer 16

• open/close ion channels
• activate membrane-bound enzymes
• G proteins and second messenger system

Question 17

Fat-soluble - signal transduction mechanism

Answer 17

After transcription of mRNA (after protein synthesis)

Question 18

Water-soluble - time of onset response, duration of response and half-life

Answer 18

Fast, short and short

Question 19

Fast-soluble - time of onset response, duration of response and half-life

Answer 19

Slow, Long and Long

Question 20

Neuron System - Secretory Cell

Answer 20

Neuron

Question 21

Neuron System - Target Cell

Answer 21

Neuron, muscle or gland

Question 22

Neuron System- Messenger

Answer 22

Neurotransmitter

Question 23

Neuron System - Pathway for communication

Answer 23

Across Synapse

Question 24

Neuron System - Basis for specificity

Answer 24

Receptors on postsynaptic target cell

Question 25

Neuron System - Time to onset effect

Answer 25

Immediate

Question 26

Neuron system - Duration of effect

Answer 26

Brief

Question 27

Endocrine System - Secretory Cell

Answer 27

Endocrine Cell

Question 28

Endocrine System - Target Cell

Answer 28

Most cell types in body

Question 29

Endocrine System - Messenger

Answer 29

Hormone

Question 30

Endocrine System - Pathway for communication

Answer 30

Via Bloodstream

Question 31

Endocrine System - Basis of specificity

Answer 31

Receptors on target cells throughout body

Question 32

Endocrine System - time of onset effect

Answer 32

Delayed

Question 33

Endocrine System - duration of effect

Answer 33

Long

Question 34

Classic Endocrine Tissues of the Body

Answer 34

- Hypothlamus - Anterior pituitary - Adrenal Glands - Pancreas - Thyroid - Sex organs - Kidneys

Question 35

Fluid Secretion into Lumen

Answer 35

- Maintining normal fluid levels - Too much loss can lead to diarrhea - Cl- and Na+ pumps are regulated by a protein kinase

Question 36

Cholera Toxin and Life Threatening Diarrhea

Answer 36

Chlolera grows under the mucus layer in the small intestine, activates G proteins and causes effluent of Cl-, Na+ and water

Question 37

Cystic Fibrosis

Answer 37

- Categorized by a homozygous mutation in the CFTR gene - Could protect against the severe loss of fluid that occurs due to th cholera toxin - Hétérozygote advantage: more likely to pass on CF gene to their offspring