The Endocrine System I

Question 1

What is the function of the endocrine system?

Answer 1

Acts with the nervous system for communication & coordination to produce homeostasis
hormones are the product of this system

Question 2

Where do hormones of once released?

Answer 2

Released into interstitial fluid and then diffuse directly into the blood or lymph

Question 3

Where do hormones go after their in the blood/lymph

Answer 3

They are carried by the blood/lymph to the target cells

Question 4

Compare hormone action & the NS

Answer 4

Hormone action is slower & longer lasting then actions produced by the nervous system

Question 5

Why do only target cells respond to the hormone?

Answer 5

Due to specificity

Question 6

What contributes to the sensitivity of hormones?

Answer 6

The # of receptors present on a target cell

Question 7

What is down regulation

Answer 7

A decrese in the # of receptors cell that is produced when the (hormone) is consistently very high

Question 8

What is the result of down regulation?

Answer 8

Decreased sensitivity

Question 9

What is up regulation

Answer 9

An increase in the # of receptor cells produced when the (hormone) is low

Question 10

What is the result of up regulation

Answer 10

Increased sensitivity of target cells

Question 11

What are the 2 things hormones can do to rxn’s?

Answer 11

Inhibit

Stimulate

Question 12

What are the major types of hormones?

2

Answer 12

Circulating

Lingering

Question 13

What are circulating hormones?

Answer 13

They are released from their gland into the lymph/blood to be sent to all body areas
Have more lingering effects.
They are eventually metabolically inactivated by the liver & excreted by the kidneys

Question 14

Describe local hormones

Answer 14

They have an effect on the cells that secreted them & nearby cells before entering the blood circulation
They tend to have a shorter action due to rapid inactivation

Question 15

What are the types of hormones (by general function)?

3

Answer 15

Tropic hormones
sex hormones
anabolic hormones

Question 16

Describe tropic hormones

Answer 16

Act by causing other endocrine glands to grow and/or secrete products

Question 17

What are sex hormones?

Answer 17

Act on reproductive tissue specifically

Question 18

What are anabolic hormones?

Answer 18

Cause tissue-building (anabolic) reactions to occur in their target cells

Question 19

How do we classify hormones (by chemical nature)

2

Answer 19

steroid hormones

Non-steroid hormones

Question 20

Describe steroid hormones

Answer 20

All contain cholesterol
They are hydrophobic
Travel in blood bound to transport & proteins which increase the stability of the hormone in the blood

Question 21

What are examples of steroid hormones?

Answer 21

Cartisol, aldosterone, estrogen, testosterone, progesterone, thyroid hormone & nitric oxide

Question 22

What is the purpose of transport proteins?

Answer 22

Prevent small hormone molecules from being filtered out of the blood into the urine (where they would be lost
Allow hormone levels in the blood to build up & provide a ready supply of additional hormones.

Question 23

What happens once a steroid hormone reaches the target cell?

Answer 23

It readily crosses the plasma membrane & the nuclear membrane to reach it’s receptor, in the nucleus

Question 24

Describe non-steroid hormones

Answer 24

Protein & amino acid derivatives
They are hydrophilic so they do not cross membranes easy
They travel in the blood freely (no proteins)

Question 25

What are some examples of steroid hormones?

Answer 25

``` Protein hormones (insulin, parathyroid growth hormones Peptide hormones (oxytocin, antidioretic AA derivatives (norepinephrine, thyroxinel) ```

Question 26

What are second messengers?

Answer 26

Used in non-steroid hormones The hormone binds to the plasma membrane & the second messenger is activated so the hormone itself never has to enter the cell

Question 27

What is hormone secretion regulated by?

Answer 27

A negative feedback mechanism

Question 28

How does the NS influence the endocrine system?

Answer 28

The NS influences the autonomic nervous system & the hypothalamus

Question 29

What is the hypophysis?

Answer 29

The pituitary gland attached to the hypothalamus (direct link to NS) Controlled by the hypothalamus Provides a distinct anatomical & brain connection Regulates many body functions 1. anterior lobe (adenohypophysis) 2. posterior lobe (neurohypophysis)

Question 30

What is the adenohypophysis?

Answer 30

Anterior pituitary "master gland" of endocrine system Composed of regular endocrine secretory cells hormones are controlled by "releasing hormones in the hypothalamus" most are stimulatory Hormone secretion is under chemical control

Question 31

What are the hormones of the adenohypophysis? | 7

Answer 31

``` Growth hormone (GH) Thyroid - stimulating hormone (TSH) Adrenocorticotropic Hormone (ACTH) follicle - stimulating hormone (FSH) Lutenizing hormone (LH) Prolactin Melanocyte - Stimulating hormone ```

Question 32

What is the growth hormone?

Answer 32

-somatotropin -stimulates the division of cells and growth in the body via protein synthesis -

Question 33

What are the disorders of GH hormones?

Answer 33

1) gypersecretion - giantism and acromegaly | 2) hyposecretion - hypopituitary dwarfism

Question 34

Whare are the 2 releasing hormones in the hypothalamus?

Answer 34

1) GHIH | 2) GHRI

Question 35

What is the thyroid stimulation hormone?

Answer 35

controlled by the thyroid releasing hormone

Question 36

What is the adrenocorticotropic hormone?

Answer 36

controls the release of cortical from the adrenal gland

Question 37

What occurs onces the hormone reaches the nucleus?

Answer 37

directly influences the DNA

Question 38

What can excessive stress cause?

Answer 38

it can override negative feedback resulting in too much cortisol

Question 39

What is the follicle-stimulating hormone?

Answer 39

triggers the onset of puberty

Question 40

What does the FSH affect in females?

Answer 40

secretion of estrogen

Question 41

What does FSH affect in men?

Answer 41

development of tubules and sperm production | also helps develop gonads

Question 42

What is gonadotropin?

Answer 42

hormone that contirbutes to gonad development

Question 43

What is the lutenizing hormone?

Answer 43

females : stimulates ovulation and the secretion of estrogen and progesterone males: stimulates testes and the release of testosterone

Question 44

What is prolactin?

Answer 44

hormone that helps to initate brease development and milk production

Question 45

What is the melanocyte stimulating hormone?

Answer 45

uncertain of true function

Question 46

What are the neurohypopjhysis?

Answer 46

posterior pituitary .. composed of neural tissue

Question 47

What hormones does the neurohypophysis secrete?

Answer 47

ocytocin and antidiuretic hormone

Question 48

What is the antidiuretic hormone?

Answer 48

promotes water reabsorbtion in the kidneys .. controls blood volume and pressure

Question 49

What does alcohol do to ADH?

Answer 49

inhibits it | results in dehydration

Question 50

What does hypsecretionof ADH cause?

Answer 50

results in diabeties inspinatus

Question 51

What is oxytocin?

Answer 51

released in large amounts during child birth | stimulates uterine contractions

Question 52

What is the pineal gland?

Answer 52

regulates the bodies biological clock

Question 53

What is melatonin

Answer 53

secreted by the pineal gland can induce sleep levels can influence the onset of puberty

Question 54

What is the thyroid gland?

Answer 54

largest endocrine gland | highly vascularized

Question 55

What hormones does the thyroid gland produce?

Answer 55

thyroid hormone and calcitonin

Question 56

What is collid?

Answer 56

throglobylin attached to iodine | gives rise to the thyroid hormone

Question 57

What are T3 cells?

Answer 57

triiodothyromine

Question 58

What are T4 cells?

Answer 58

tetraiodthyronine

Question 59

What is affected by the thyroid hormone

Answer 59

everything except the brain,testes, uterus, spleen and the gland itself

Question 60

How hows TH affect tissue production?

Answer 60

aids in tissue growth and development | especially skeletal and nervous tissue

Question 61

What carries T3 and T4 in the blood?

Answer 61

proteins: 1) thyroxine 2) abumin

Question 62

What happens when our body lacks iodine

Answer 62

enlargement of the thyroid gland | called a goiter

Question 63

What is graves disease?

Answer 63

hypersecretion of the thyroid hormone

Question 64

What is cretinism?

Answer 64

hyposecretion of the thyroid hormone

Question 65

What is myxedema?

Answer 65

hyposecretion of TH in adults