Exam 1 - Ch. 3 Chemical signaling

Question 1

Presynaptic transmitting

Answer 1

process that releases the chemical messenger/neurochemicals

Question 2

Postsynaptic receptive

Answer 2

process determines binding of transmitter to receptor molecule in postsynaptic cell

Question 3

Neurotransmitter

Answer 3

chemical substances released by neurons to communicate with other neurons

Question 4

What is the criteria of an NT?

Answer 4

• neuron has to be able to produce and store the NT
• there has to be a way to deactivate the NT
• there are postsynaptic receptors specific to it
• if agonists or antagonists are applied, they will act appropriately

Question 5

What are the processes involved in synaptic neurotrasmission?

Answer 5

AP, presynaptic release of NT, postsynaptic receiving of NT (use fig from slides)

Question 6

Where are NTs made in small-molecule transmitters? In peptide transmitters?

Answer 6

• terminal buttons for quick release
• cell bodies

Question 7

Which channels are excitatory?

Answer 7

sodium channels

Question 8

Where are NTs released into, and what are they released from?

Answer 8

they are released into the active zone from the synaptic vesicles through exocytosis

Question 9

What chemical is involved in the docking, fusion and exocytosis of synaptic vesicles? What else is this chemical involved in?

Answer 9

• calcium
• release of NT

Question 10

What 4 factors control the rate of NT release?

Answer 10

• rate of neuron firing
• probability of transmitter release from axon terminal
• presence of autoreceptors
• axon terminals may have heteroreceptors

Question 11

What are autoreceptors?

Answer 11

inhibitory receptors on the presynaptic cell, decrease synthesis and release of NTs once they sense that there is a lot

Question 12

Synaptic vessels are filled with NTs due to what channels opening?

Answer 12

calcium

Question 13

What are the 3 methods of NT inactivation?

Answer 13

• enzymatic breakdown
• reuptake (transporter proteins will take the NT into storage or another vesicle)
• uptake by glial cells (astrocytes have their own transporter proteins)

Question 14

Ionotropic receptors

Answer 14

• directly gates a channel
• quick, short term (movement)
• K+, Ca2+ channels, etc

Question 15

Metabotropic

Answer 15

• gate ion channels indirectly
• longer duration, slower (memory and learning)

Question 16

Tyrosine Kinase receptors

Answer 16

mediate action of neurotrophic factors (growth and survival of neurons)

Question 17

Drugs can act as either agonists or antagonists. True or false? Explain.

Answer 17

True
- can act as a precursor or inhibit synthesis of NTs
- prevent storage in vesicles
- inhibit or stimulate the release of NTs
- stimulate or block postsynaptic receptors
- inhibit or stimulate autoreceptors
- inhibits degradation of NTs
- blocks NT reuptake

Question 18

Endocrine system, what are some of the things that this system controls?

Answer 18

• controls body functions by releasing hormones
• reproduction, growth and development, mobilization of body defenses, regulation of metabolism

Question 19

What are the 3 classes of hormones?

Answer 19

1. Amino acid derivatives (adrenaline or noradrenaline)
2. Peptide and protein hormones (insulin, neuropeptide Y)
3. Steroid hormones (estrogen)

Question 20

What are some hormonal effects?

Answer 20

• changes in plasma membrane permeability or electrical state
• synthesis of proteins such as enzymes
• activation or inactivation of enzymes

Question 21

What is the difference between steroid hormone and nonsteroid hormone action?

Answer 21

the receptor of a steroid hormone is inside the nucleus, the receptor protein of a nonsteroid hormone is external

Question 22

Adrenal cortex

Answer 22

excrete glucocorticoids

Question 23

Adrenal medulla

Answer 23

excrete epinephrine and norepinephrine

Question 24

What two hormones do the pancreas excrete?

Answer 24

insulin and glucagon

Question 25

Pineal gland

Answer 25

secretes melatonin

Question 26

Thymus

Answer 26

• T-cells mature and are produced here
• produces thymosine, which matures some types of WBCs and is important in developing the immune system

Question 27

Estrogens

Answer 27

• produced by ovaries
• development of secondary female characteristics
• matures female reproductive organs

Question 28

Progesterone

Answer 28

• produced by the corpus luteum
• acts with estrogen to bring about the menstrual cycle

Question 29

Testosterone

Answer 29

• responsible for adult male secondary sex characteristics and growth and maturation of male reproductive system
• required for sperm production