Chapter 17 - Endocrine System

Question 1

Exocrine Glands

Answer 1

Nonhormonal substances with ducts (sweat, saliva)

Question 2

Endocrine Glands

Answer 2

Produce hormones and lack ducts

Question 3

Hormones

Answer 3

long-distance chemical signals; travel in blood or lymph

Question 4

Autocrines

Answer 4

exert effects on same cells that secrete them

Question 5

Paracrines

Answer 5

locally acting, affect cells other than those that secrete them

Question 6

What Hormones do

Answer 6

• Alter plasma membrane permeability membrane potential by opening or closing ion channels
• Stimulate synthesis of proteins
• Activate or deactivate enzymes
• Induce secretory activity
• Stimulate mitosis

Question 7

Water-Soluble Hormones

Answer 7

All amino acid–based hormones except thyroid hormone
• Act on plasma membrane receptors
• Via G protein second messengers
•Cannot enter cell

Question 8

Lipid-Soluble Hormones

Answer 8

• steroid and thyroid hormones

* Enters cell to act on intracellular receptors that directly activate genes

Question 9

Target Cells

Answer 9

Target cells must have specific receptors to which hormone binds, for example

Question 10

Target cell activation depends on

Answer 10

1. Blood levels of hormone
2. Number of receptors on or in target cell
3. Affinity of binding between receptor and hormone

Question 11

Hormonal Up-Regulation

Answer 11

target cells form more receptors in response to low hormone

Question 12

Hormonal Down-Regulation

Answer 12

target cells lose receptors in response to high hormone

Question 13

3 Types of Activations

Answer 13

Humoral Stimulus - hormone release caused by altered levels of ion or nutrient, i.e. low Ca2+, Parathyroid releases PTH to increase Ca2+

Neural Stimulus - Hormone release due to neural input, i.e. Ap to Adrenal Medulla to release Epi and Norepi.

Hormonal Stimulus - Hormone released because of another hormone (tropic hormone) Hormone from Hypothalamus to anterior pituitary gland to release other hormone.

Question 14

Posterior Pituitary Hormones

Answer 14

Oxytocin and Antidiuretic Hormone

Question 15

Anterior Pituitary Hormones

Answer 15

Growth hormone, TSH, ACTH, FSH, LH, PRL

Question 16

Roles of Oxytocin

Answer 16

stimulates uterine contraction
trigger for milk
neurotransmitter in brain

Question 17

Roles of ADH

Answer 17

inhibits or prevents urine formation
targets kidney tubules to reabsorb water
inhibited by alcohol

Question 18

Growth Hormone

Answer 18

Indirect Mechanism
stimulates adipose cells to break down stored fat,
fueling growth effects,
increases uptake of amino acids from the blood
enhances cellular proliferation
reduces apoptosis,

all promote the growth of target cells in the bones, muscles, nervous and immune systems

Direct Mechanism - fat and carbohydrate metabolism which fuels the processes

Question 19

Thyroid Stimulating Hormone (TSH)

Answer 19

• Produced by thyrotropic cells of anterior pituitary
• Stimulates normal development and secretory activity of thyroid
• Release triggered by thyrotropin-releasing hormone from hypothalamus
• Inhibited by rising blood levels of thyroid hormones that act on pituitary and hypothalamus

Question 20

Adrenocorticotropic Hormone (ACTH)

Answer 20

• Secreted by corticotropic cells of anterior pituitary
• Stimulates adrenal cortex to release corticosteroids
• Triggered by hypothalamic corticotropin-releasing hormone (CRH) in daily rhythm

Question 21

Follicle Stimulating Hormone (FSH)

Answer 21

• Secreted by gonadotrophs of anterior pituitary
• FSH stimulates gamete production
• Triggered by gonadotropin-releasing hormone (GnRH) during and after puberty

Question 22

Luteinizing Hormone (LH)

Answer 22

• Secreted by gonadotrophs of anterior pituitary
• LH promotes production of gonadal hormones
• Triggered by gonadotropin-releasing hormone (GnRH) during and after puberty

Question 23

Prolactin (PRH)

Answer 23

• Regulation of PRL release controlled by prolactin-inhibiting hormone (PIH)
• Suckling stimulates PRL release and promotes continued milk production
• Hypersecretion causes inappropriate lactation, lack of menses, infertility in females, and impotence in males

Question 24

Thyroid

Answer 24

Hormone: increase metabolic rate, heat production, regulation of tissue growth and development, maintenance of blood pressure.
Hyposecretion=myxedema, cretinism
Hypersecretion=graves disease

Question 25

Colloid

Answer 25

Raw material that makes thyroid hormone

Question 26

Calcitonin

Answer 26

Antagonist to Parathyroid Hormone (PTH) Inhibits osteoclast activity and release of Ca2+ from bone matrix, stimulates Ca2+ uptake and incorporation into bone matrix.

Question 27

Parathyroid

Answer 27

On back of thyroid, Negative feedback loop to control the Ca2+ hyperparathyroidism softens bones, kidney stones hypoparathyroidism = Results in tetany, respiratory paralysis, and death in

Question 28

Adrenal Gland

Answer 28

Adrenal Medulla = Nervous Tissue Adrenal Cortex = Glandular Tissue • Zona Glomerulosa = Release Aldosterone • Zona Fasciculata (biggest) = Release Cortisol and androgens • Zona Reticularis = NE and Epine

Question 29

Mineralocorticoids

Answer 29

Regulate electrolytes Aldosterone: most potent mineralocorticoid Stimulates Na+ reabsorption and water retention by kidneys; elimination of K+ Release triggered by: •Decreasing blood volume and blood pressure •Rising blood levels of K+

Question 30

Glucocorticoids

Answer 30

Cortisol •Released in response to ACTH, patterns of eating and activity, and stress •Promotes gluconeogenesis—formation of glucose from fats and proteins •"Saves" glucose for brain •Enhances vasoconstriction rise in blood pressure to distribute nutrients to cells

Question 31

Hormones of Adipose Tissue

Answer 31

Leptin - appetite control Resistin - insulin antagonist Adiponectin - sensitivity to insulin

Question 32

Hormones of Kidneys

Answer 32

Erythropoietin - red blood cell production | Renin - initiates the renin angiotension

Question 33

Hormones of heart

Answer 33

Atrial Natriuretic Peptide - Blood pressure

Question 34

Pineal gland

Answer 34

Secretes melatonin - timing of sexual maturation and puberty, Day/night cycle, body temp, sleep, appetite

Question 35

Pancreas

Answer 35

``` Acinar cells (exocrine) produce enzyme rich juice for digestion. Pancreatic islet contains endocrine cells, Alpha cells produce Glucagon Beta cells produce Insulin ```

Question 36

Glycogenolysis

Answer 36

Glycogen to glucose

Question 37

Gluconeogenesis

Answer 37

Synthesis of glucose

Question 38

3 signs of Diabetes Mellitus

Answer 38

Polyuria - huge urine output, glucose acts as osmotic diuretic Polydipsia - Excessive thirst from water loss of polyuria Polyphagia - Excessive hunger and food consumption, cells can't take up glucose so start to starve.

Question 39

Hyperinsulinism

Answer 39

Excessive insulin release causes HYPO Glycemia

Question 40

Estrogen

Answer 40

Produced in ovaries, maturation of reproductive organs, appearance of secondary sexual characteristics

Question 41

Progesterone

Answer 41

breast development, and cyclic changes in uterine mucosa

Question 42

Testosterone

Answer 42

produced in testes