chapter 18 endocrine system

Question 1

the whole function of the endocrine system

Answer 1

Endocrine cells and tissues produce about 30 different hormones (chemical messengers)

Controls and coordinates body processes

Question 2

what are the 4 types of intercellular communication

Answer 2

Direct communication

Paracrine communication

Autocrine communication

Endocrine communication

Question 3

Exchange of ions and molecules between adjacent cells across gap junctions
Occurs between two cells of the same type
Highly specialized and relatively rare

which intercellular communication?

Answer 3

Direct communication

Question 4

Chemical signals transfer information from cell to cell within a single tissue

which intercellular communication?

Answer 4

Paracrine communication

Question 5

Messages affect the same cells that secrete them
Chemicals involved are autocrines

Example: prostaglandins secreted by smooth muscle cells cause the same cells to contract

which intercellular communication?

Answer 5

Autocrine communication

Question 6

Endocrine cells release chemicals (hormones) that are transported in bloodstream

Alters metabolic activities of many organs

which intercellular communication?

Answer 6

Endocrine communication

Question 7

the endocrine communication has what type of cell and it functions

Answer 7

Target cells

Have receptors needed to bind and “read” hormonal messages

Question 8

the function of hormones

Answer 8

Change types, quantities, or activities of enzymes and structural proteins in target cells

Can alter metabolic activities of multiple tissues and organs at the same time

Affect long-term processes like growth and development

Question 9

the function of the synaptic communication

Answer 9

Neurons release neurotransmitters at a synapse

Leads to action potentials that are propagated along axons

Allows for high-speed “messages” to reach specific destinations

Ideal for crisis management

Question 10

Both endocrine and nervous systems do?

Answer 10

Rely on release of chemicals that bind to specific receptors on target cells

Share many chemical messengers (e.g., norepinephrine and epinephrine)

Are regulated mainly by negative feedback

Function to preserve homeostasis by coordinating and regulating activities

Question 11

the endocrine system what do they produce and where is it release?

Answer 11

that produce hormones or paracrines

Endocrine cells release secretions into extracellular fluid

Endocrine organs are scattered throughout body

Question 12

what are the 3 types of hormones

Answer 12

Amino acid derivatives
Peptide hormones
Lipid derivatives

Question 13

amino acid derivates also means

Answer 13

biogenic amines

Question 14

what are examples of Peptide Hormones, types of protein

Answer 14

Glycoproteins
Proteins more than 200 amino acids long that have carbohydrate side chains (e.g., TSH, LH, FSH)

Question 15

how do hormones travel

Answer 15

Hormones may circulate freely or travel bound to special carrier proteins

Question 16

Free hormones remain functional for less than an hour and are inactivated when they

Answer 16

Diffuse out of bloodstream and bind to receptors on target cells,

Are absorbed and broken down by liver or kidneys, or

Are broken down by enzymes in blood or interstitial fluids

Question 17

what are the effects of binding hormones

Answer 17

Alter genetic activity
Alter rate of protein synthesis
Change membrane permeability

Question 18

receptors absence determines what?

Answer 18

receptor determines hormonal sensitivity of a cell

Question 19

what are the 2 types of regulation

Answer 19

Down-regulation = Presence of a hormone triggers a decrease in the number of hormone receptors

Up-regulation= Absence of a hormone triggers an increase in the number of hormone receptors

Question 20

which hormones are able to pass through membranes

Answer 20

Steroid and thyroid hormones
Lipid soluble
intracellular receptors

Question 21

Catecholamines and peptide hormones

Answer 21

Not lipid soluble

Unable to penetrate plasma membrane

Bind to receptor proteins on outer surface of plasma membrane (extracellular receptors)

Question 22

what does each messenger do ?

Answer 22

First messenger
Hormone that binds to extracellular receptor
Promotes release of second messenger in cell

Second messenger
Intermediary molecule that appears due to hormone–receptor interaction

May act as enzyme activator, inhibitor, or cofactor

Results in change in rates of metabolic reactions

Question 23

what are the affects of G proteins and CAMp levels

Answer 23

increasing cAMP level, which accelerates metabolic activity of cell
increase in cAMP level is usually short-lived

Question 24

Steroid hormones

Answer 24

can alter rate of DNA transcription in nucleus

Alterations in synthesis of enzymes or structural proteins
Directly affect activity and structure of target cell

Question 25

Thyroid hormones

Answer 25

bind to receptors within nucleus and on mitochondria

Activate genes or change rate of transcription
Increase rates of ATP production

Question 26

hormones can be triggered by

Answer 26

Humoral stimuli (change in composition of extracellular fluid),

Hormonal stimuli (arrival or removal of hormone),

Neural stimuli (neurotransmitters at neuroglandular junctions)