communication, integration, and homeostasis-chp6

Question 1

what is responsible for most communication within the body?

Answer 1

chemical signals

Question 2

what are some types of physiological signals?

Answer 2

electrical signals and chemical signals

Question 3

electrical signals

Answer 3

changes in the membrane potential of a cell

Question 4

chemical signals

Answer 4

neurotransmitters/hormones
they are secreted into the ECF
responsible for most communication within the body

Question 5

what responds to signals?

Answer 5

target cells or targets

Question 6

what do Gap Junctions do?

Answer 6

they form direct cytoplasmic connections between adjacent cells.
they are super prevalent in the heart.

Question 7

autocrine signals

Answer 7

act on the same cell that secreted them.

Question 8

Paracrine signals

Answer 8

are secreted by one cell and diffuse to adjacent cells.

Question 9

Hormones are secreted by ______ glands or cells into the blood. only____ cells with ____ receptors for the hormone respond to the signal.

Answer 9

Hormones are secreted by endocrine glands or cells into the blood. Only target cells with receptors for the hormone respond to the signal.

Question 10

what are neurocrines?

Answer 10

chemical signals secreted by neurons like:
neurotransmitters
neuromodulators
neurohormones

Question 11

neurotransmitters:

Answer 11

chemicals secreted by neurons that diffuse across a small gao to the target cell.

Question 12

Neurohormones

Answer 12

chemicals released by neurons into the blood for action at distant targets.
Ex:hypothalamus to pituitary
These are the ones that will only bind to target cells that have the receptors for them

Question 13

what are the five steps of signal pathways?

Answer 13

1-signal molecule
2-binds to membrane receptor protein 
3-activates intracellular signal molecules
4-alter target proteins
5-create response

Question 14

what are the different types of membrane receptors?

Answer 14

Receptors channel (chemically gated)
receptor-enzyme
G-protein-coupled receptor
integrin receptor

Question 15

Receptor Channel (chemically gated)

Answer 15

ligand binding opens or closes the channel

Question 16

Receptor-enzyme

Answer 16

ligand binding to a receptor-enzyme activates an intracellular enzyme

Question 17

G-protein coupled receptor

Answer 17

ligand binding to a G protein couples receptor opens an ion channel or alters enzyme activity. there are more of these than any other in the body. It doesn’t have a pore, nothing goes across.

Question 18

Integrin Receptor

Answer 18

ligand binding to integrin receptors alters the cytoskeleton

Question 19

tyrosine kinase receptor

Answer 19

transfers a phosphate group from ATP to a tyrosine (an AA) of a protein

Question 20

What do G proteins do when they are activated?

Answer 20

open ion channels in the membrane

alter enzyme activity on the cytoplasmic side of the membrane.

Question 21

what are the different second messengers?

Answer 21

cAMP
cGMP
IP3
DAG
Ca2+

Question 22

cAMP

Answer 22

made from ATP
activates protein kinases, especially PKA.
binds to ion channels
phosphorylates proteins. Alters channel opening,

Question 23

cGMP

Answer 23

made from GTP.
activated protein kinases especially PKG
binds to ion channels
it phosphorylates proteins and alters chennel opening

Question 24

IP3

Answer 24

made from membrane phospholipids
releases Ca from intracellular stores
same effects as Ca

Question 25

DAG

Answer 25

made from phospholipids activates protein kinase C it phosphorylates proteins

Question 26

Ca2+

Answer 26

``` binds to calmodulin and other proteins alters enzyme activity exocytosis muscle contraction cytoskeleton movement channel opening ```

Question 27

what are the steps of the GPCR adenylyl transduction signal transduction and amplification?

Answer 27

a signal molecule binds to g protein coupled receptor which activated G protein G protein then activates adenyl cyclase which is an amplifier enzyme which then concerts ATP to cAMP . cAMP activated protein kinase A which phosphorylates other proteins leading to a cellular response.

Question 28

describe the g coupled protein receptor (GPCR) phospholipase C signal transduction

Answer 28

a signal molecule activates the receptor which activated the G protein G protein then activated phospholipase C (PLC) which is an amplifier enzyme. PLC then concerts membrane phospholipid into DAG (which stays an in the membrane) and IP3 which diffuses into the cytoplasm. DAG activates protein kinase C (PKC) which phosphorylates proteins and IP3 causes Ca2+ release from organelles which creates a Ca signal

Question 29

signal transduction using ion channels

Answer 29

receptor channels open or close in response to signal molecule binding. some channels are directly linked to G proteins that when GPCR are activated the channels open. then there are some channels that open as a response to intracellular second messengers.

Question 30

how does Ca induce a response?

Answer 30

Ca is generally pretty low in cells so when it does increase we know that there is an important message.

Question 31

How is Nitric oxide produced and where does it go?

Answer 31

NO is produced by endothelial cells (and neurons) and can just diffuse through membranes into smooth muscle and causes vasodilation

Question 32

how is Nitric Oxide (NO) synthesized?

Answer 32

by the action of nitric oxide synthase (NOS)

Question 33

What does NO activate?

Answer 33

it activates guanylyl cyclase (which takes guanine from GTP) and forms cGMP.

Question 34

What does NO act as?

Answer 34

A neurotransmitter an neuro modulator in the brain

Question 35

Carbon Monoxide (CO)

Answer 35

Also activates guanylyl cyclase and form cGMP. | it targets smooth muscle and neural tissue

Question 36

Leukotrienes

Answer 36

play a role in asthma and anaphylaxis

Question 37

what are some prostanoids

Answer 37

prostaglandins thromboxanes sphingolipids

Question 38

prostaglandins

Answer 38

sleep, inflammation, pain, fever | nonsteroidal anti-inflammatory drugs (NSAIDs) help prevent inflammation by inhibiting cyclooxygenase

Question 39

sphingolipids

Answer 39

help regulate inflammation, call adgesion and migration, and cell growth and death.

Question 40

down-regulation

Answer 40

decrease in receptor number

Question 41

up-regulation

Answer 41

inserts more receptors in cell membrane

Question 42

what are different uses of the word receptor?

Answer 42

cell membrane or intracellulsr receptor proteins | sensors which are specialized cells that concert various stimuli into electrical signals