Endocrine System

Question 1

is a molecule—protein or steroid—secreted into the bloodstream to affect distant body parts.

Answer 1

Endocrine Hormone

Question 2

Hormones exert effects on target cells by binding to______

Answer 2

receptors

Question 3

To stop hormones effect from lasting forever, hormones must be ____

Answer 3

cleared

Question 4

Most metabolic clearance is done by___

Answer 4

Kidney and Liver

Question 5

Based on molecular structure, there are 3 major categories of hormones?

Answer 5

Amines (aa= tyrosine), peptides (aa: made by hormone-secreting cells , and steroids (highly-cyclized lipids)

Question 6

How is receptor deactivated?

Answer 6

• Receptor: Hormone complex may be endocytosed and degraded (Endocytosis)

Question 7

Highly polar

Answer 7

Amines

Question 8

Examples OF Amines

Answer 8

• catecholamines, epinephrine, norepinephrine, and dopamine.

Question 9

Large size and polarity means they dissolve in water, cant cross

Answer 9

Peptide hormones

Question 10

Lipophilic; they can cross cell membrane

Answer 10

Steroid hormones

Question 11

____ of hormones largely determines its mechanism of action

Answer 11

Structure of hormone

Question 12

The catecholamine epinephrine and all the peptide hormones are _____and ______.

Answer 12

large; hydrophillic

Question 13

Exert their effects by binding and activating a membrane receptor—cannot cross cell membranes themselves.

Answer 13

catecholamines and peptides

Question 14

These intracellular pathways modify the activity of already existing proteins, usually by ______.

Answer 14

phosphorylation

Question 15

Steroid hormones are lipophilic, allowing them to ______across membranes from the blood into cells.

Answer 15

diffuse

Question 16

Exert their effects by crossing cell membranes and binding to an intracellular receptor.

Answer 16

Steroids

Question 17

Steroids act as ___

Answer 17

a transcription factor or activates other transcription factors.

Question 18

Duration of steroids’ action

Answer 18

Long (slow)- —days to weeks, depending on how long cell keeps its proteins around.

Question 19

Despite its steroidal characteristics, why do thyroid hormones exert brief episodes

Answer 19

Contain iodine in their structure

Question 20

• is an important regulatory/homeostatic center on the underside of the brain.

Answer 20

Hypothalamus

Question 21

d is a cluster of cells hanging off the hypothalamus

Answer 21

Pituitary glands

Question 22

□ Stalk of tissue called :_____connects the pituitary gland to the hypothalamus.

Answer 22

infundibulum

Question 23

The infundibulum is made of different types of tissue for the two halves of the pituitary.

Answer 23

• In anterior pituitary: blood vessels link the hypothalamus to the pituitary.
• In posterior pituitary: axons of neurons link the hypothalamus to the pituitary.

Question 24

Axons that make synpases into capillary beds in the posterior pituitary itself

Answer 24

Axons of the pituitary

Question 25

Hormones released from axons of posterior pituitary glands

Answer 25

Neurohormone

Question 26

2 hormones released by posterior pituitary glands:

Answer 26

• Oxytocin: Breastfeeding= important in child birth and lactation
• Vasopressin (aka: ADH): Helps maintain blood pressure via: Water-Na+ retention

Question 27

______ is the general name for this highly unusual arrangement of two capillary beds in a row

Answer 27

Portal System:

Question 28

Name of the portal system that connects hypothalamus and adenohypophysis

Answer 28

Hypothalamo-Hypophyseal portal system

Question 29

—secreted by hypothalamic neurons into the portal system

Answer 29

releasing hormones

Question 30

Hormones released by anterior pituitary glands

Answer 30

• Follicle-stimulating hormone (FSH),
• Luteinizing hormone (LH),
• Adrenocorticotrophic hormone (ACTH)
• Thyroid stimulating hormones (TSH),
• Prolactin (PRL), and growth hormone (GH).

Question 31

Refer to pg.10

Answer 31

Refer to pg.10

Question 32

____is a gland in the neck, just below larynx. Produces two hormones: triiodothyronine (T3) and Thyroxine (T4).

Answer 32

Thyroid

Question 33

Thyroid hormones cause: _________.

Answer 33

-↑transcription/translation of Na+/K+ ATPases.

• ↑Na+/K+ ATPases→↑ATP use.
• ↑Heat production, ↑Aerobic Metabolism to replace ATP.

Question 34

a pair of glands, one sitting atop each kidney

Answer 34

Adrenal gland

Question 35

secretes steroids: aldosterone, the sex hormones (testosterone, estrogen, etc.), and cortisol.

Answer 35

Adrenal Cortex

Question 36

acts on kidneys, promotes H2O and Na+ retention→↑Blood pressure.

Answer 36

Aldosterone

Question 37

Sex hormones that determine secondary sex characteristics

Answer 37

• Testosterone: Muscle production

- Estrogen: Increases body fat ( especially hips thigh, breasts) role in control of mensural cycle

Question 38

How does Cortisol play an important part of the “stress” response:

Answer 38

• ↑Gluconeogenesis and ↑β-oxidation→more energy.
• ↑Muscle breakdown→use proteins for energy.
• ↓Inflammation (that’s the clinical use).
• Controlled by Hypothalamus-Anterior Pituitary-Adrenal (HPA) ( negative feedback loop).

Question 39

secretes catecholamines, epinephrine into general circulation

Answer 39

Adrenal Medulla

Question 40

major hormone of the sympathetic nervous system→”fight-or-flight” effects

Answer 40

Epinephrine ( Adrenaline)

Question 41

Effects of Epinephrine ?

Answer 41

( Increases HR, blood pressure, glycogenolysis, B-oxidation)