LECTURE 1

Question 1

The Endocrine System works closely with what other system?

Answer 1

Nervous System

Question 2

The Endocrine system is fast or slow? Are the Effects short or long lasting?
Explain why.
Answer the same for the Nervous System.

Answer 2

The Endocrine system is slow because it releases it’s hormones into the blood stream. The effects however, are long lasting.
The Nervous System is fast acting because it travels across a synapse. It’s effects are shorter.

Question 3

What are the following for the Endocrine System:

1. Effector tissues
2. Effector cells
3. Chemical messenger
4. Secreting cells
5. Distance chemical travels
6. Receptor location
7. Speed
8. Duration

Answer 3

1. Effectors: virtually all tissues
2. Effector Cells: Target cells
3. Chemical Messengers: Hormone
4. Secreting Cells: Glandular epithelial cells
5. Distance: Long (via blood)
6. Receptor Location: Plasma membrane or inside the cell
7. Speed: Slow
8. Duration: Long-lasting

Question 4

What are the following for the Nervous System:

1. Effector tissues
2. Effector cells
3. Chemical messenger
4. Secreting cells
5. Distance chemical travels
6. Receptor location
7. Speed
8. Duration

Answer 4

1. Effectors: muscle and glands only
2. Effector Cells: Postsynaptic cell
3. Chemical Messenger: Neurotransmitter
4. Secreting Cells: Neurons
5. Distance: Short (across synapse)
6. Receptor Location: Plasma membrane
7. Speed: Fast
8. Duration: Short-lived

Question 5

Endocrine Glands are known as “___less” glands

Answer 5

Ductless

Question 6

What is a Tropic hormone/ How do they work?

Answer 6

Hormones that target OTHER endocrine glands and stimulate THEIR secretion

Question 7

What are Sex Hormones/How do they work?

Answer 7

Hormones that target reproductive tissues

Question 8

What are Anabolic hormones/ How do they work?

Answer 8

Hormones that stimulate anabolism in target cells
Ex. Anabolic steroids.
-THEY HELP BUILD AND GROW

Question 9

Steroids are synthesized from what?
Are they or are they not lipid soluble?
Are they able to easily pass through the phospholipid plasma membrane of target cells?

Answer 9

All synthesized from cholesterol

LIPID SOLUBLE and can easily pass through the phospholipid plasma membrane of target cells

Question 10

Name the 6 steroids we will be focusing on…

Perry, Cute, Cuddly, Toddler, Even, Cholesterol

Answer 10

Progesterone, Corticosterone, Cortisol, Testosterone, Estradiol, Cholesterol

Question 11

What are Non-Steroid Hormones synthesized from?

As well as protein hormones.

Answer 11

Synthesized from Amino Acids (building blocks of proteins)

Protein Hormones –> Long chains of amino acids.

Question 12

What are two examples of protein hormones?

Answer 12

Parathyroid Hormone and Insulin are both examples of protein hormone.

Question 13

Do peptide hormones have long or short chains of amino acids?
What are two examples of this?

Answer 13

Peptide Hormones have SHORTER chain of amino acids
Ex.
1. Oxytocin
2. ADH( antidiuretic hormone)

Question 14

What is a Amino Acid Derivative?

What is an example of this?

Answer 14

Derived from a single amino acid.

Ex. T4 (thyroid hormone)

Question 15

What is a Glycoprotein hormone?
Similar to protein hormone.
Exception is the sugars that the glycoprotein has.

Answer 15

Contains sugars, Similar to protein hormone.

Exception is the sugars that the glycoprotein has.

Question 16

What hormone is detected on pregnancy tests?

Answer 16

hCG (pregnancy hormone) - detected in blood and urine.

Question 17

Describe how hormones travel to their specific receptor cell in the Endocrine system.

Answer 17

An endocrine gland produces a hormone - it goes into the blood - then travels to the target tissue that has a specific receptor

Receptor must be working or it will not bind.Lock and Key

Question 18

Hormones have primary effects, but may also have multiple secondary effects. TRUE OR FALSE?

Answer 18

true.

Question 19

Endocrine glands produce more hormone molecules than are actually needed. What happens to the unused ones?

Answer 19

The unused hormones are quickly excreted by the kidneys or broken down by metabolic processes

Question 20

COMBINED HORMONE ACTIONS

Describe Synergism (TOGETHER)

Answer 20

Combinations of hormones acting together have a greater effect on a target cell than the sum of the effects that each would have if acting alone

Question 21

COMBINED HORMONE ACTIONS

Describe Permissiveness (HELP)

Answer 21

When a small amount of one hormone allows a second one to have its full effects on a target cell. One hormone permits another hormone to do the job that it needs to do in order for it to have it’s full effect.

Question 22

COMBINED HORMONE ACTIONS

Describe Antagonism (OPPOSITION)

Answer 22

One hormone produces the opposite effects of another hormone; used to “fine tune” the activity of target cells with great accuracy. Working in opposition for control

Question 23

The second messenger system is a form of ________

Answer 23

Signal Transduction

Question 24

MECHANISM OF STEROID HORMONE

Where are the steroid hormones receptors found? What do they form when they bind to it?

Answer 24

Receptors are found in the target cell’s cytosol or nucleus.

Steroid hormones bind to a receptor to form a hormone-receptor complex

Question 25

MECHANISM OF STEROID HORMONE 2 In the mobile-receptor model is the receptor stationary or moving? What is this sequence initiation the synthesis of? Is the response slow or fast?

Answer 25

Receptor is mobile. Moving around. Vs. a Fixed Receptor that does not move & is fixed within the plasma membrane. The receptor moves and binds to a gene sequence to initiate protein synthesis The response to steroid hormones is slow as protein synthesis takes time

Question 26

MECHANISM OF A NON-STEROID HORMONE If non-steroid hormones are not lipid-soluble, how do they carry out actions inside of the cell? Why are the actions of non-steroid hormones faster than the actions of steroid hormones? What is another example of a 2nd messenger system?

Answer 26

2nd messenger system. 1. A non-steroid hormone's (“first messenger”) binds to fixed receptors in the target cell’s plasma membrane 2. Receptor triggers 2nd messenger to activate an existing protein response A form of SIGNAL TRANSDUCTION -Occurs with this model because it is a message being communicated from outside the cell to inside the cell FASTER BECAUSE... When the hormone binds to the cells, the effects are amplified by the cascade of activities that happen within the cell. Therefore --a lot faster than the steroid mechanism Another example of 2nd messenger system: Calcium Calmodulin Opens up channels permitting calcium to move into the cell. Looks for receptor which is called calmodulin. -forms calcium calmodulin complex.

Question 27

Answer the following for a STEROID HORMONE 1. Structure 2. Stored in secretory cell 3. Receptor 4. Action 5. Response time

Answer 27

STEROID 1. Lipid 2. Stored on Secretory Cell? No 3. Receptor: Mobile in cytoplasm or nucleus 4. Action: Regulates gene expression --> protein synthesis 5. Response Time: 1hr - days

Question 28

Answer the following for a NON-STEROID HORMONE 1. Structure 2. Stored in secretory cell 3. Receptor 4. Action 5. Response time

Answer 28

1. Structure: >1 amino acid ± sugars 2. Stored in Secretory Cells? Yes 3. Receptor: Fixed in plasma membrane 4. Action: Triggers intracellular 2nd messenger pathway to activate a protein 5. Response time: Secs - mins

Question 29

The control of hormonal secretions is a positive or negative feedback loop? What are some other ways hormones are regulated in the Endocrine System?

Answer 29

Control of hormonal secretion is usually part of a negative feedback loop and is called endocrine reflexes 2. Endocrine gland secretion may also be regulated by a hormone produced by ANOTHER gland 3. Endocrine gland secretions may be influenced by nervous system input. REMEMBER THEIR CORRELATION.

Question 30

An example of Eicosanoids are ______. They behave locally, true or false? What are some other examples of Eicosanoids.

Answer 30

Prostaglandins TRUE: They behave locally do NOT travel distances in the body. OTHER EXAMPLES: Prostaglandin, Thromoxane, and Leukotriene Prostaglandins -TISSUE HORMONES because they affect the tissue they are secreted in. Have effects on neighbouring cells.

Question 31

What are the functions of the three prostaglandins, PGA, PGE & PGF? A- UNDA PRESSA B-HELP MA FEEVA C-PUSHH

Answer 31

``` Prostaglandin A (PGA)— immediate fall in blood pressure accompanied by an increase in regional blood flow to several areas. ``` ``` Prostaglandin E (PGE)— systemic inflammation Ex. Fever (which can be blocked with drugs that inhibit PG-producing enzymes such as COX-1 and COX-2); Blocks enzymes that produce these prostaglandins that are causing the fever. Gastrointestinal effects: regulates hydrochloric acid secretion. ``` ``` Prostaglandin F (PGF)— especially important in reproductive system, causing uterine contractions; ```

Question 32

REGULATION OF TARGET CELL SENSITIVITY: Describe what Up and Down regulation are.

Answer 32

Up-regulation—increased number of hormone receptors increases sensitivity Down-regulation—decreased number of hormone receptors decreases sensitivity

Question 33

Name 3 Endocrine Disorders.

Answer 33

1. Diabetes mellitus Deficiency of insulin or a decreased response to insulin in target tissues *Best known endocrine disorder Pancreas does not produce enough insulin OR tissues have issue taking glucose to make energy. 2. Gigantism Pituitary gland Excess growth hormone  Starts in childhood In adulthood it is called acromegaly 3. Goiter enlarged thyroid gland If no dietary iodine (iodine essential for thyroid function)