ENDOCRINE SYSTEM

Question 1

• responsible for the synthesis and secretion of chemical messenger known as hormones which are disseminated throughout the body via the bloodstream where they act on specific target organs.
• the secretory cells release their hormones into the interstitial space from which they are rapidly absorbed into the circulation.
• Unlike exocrine glands, _______________ have no duct system and therefore sometimes called the ductless glands.

Answer 1

Endocrine Glands

Question 2

Endocrine Glands is also called the

Answer 2

ductless glands

Question 3

are highly vascular and you have blood vessels that are fenestrated (there are holes for the passage of large molecules)

Answer 3

Endocrine organs

Question 4

Types of Endocrine Glands

Answer 4

• Pituitary Gland

Question 5

➢ a specialized appendage of the brain which secretes several hormones.
➢ small slightly elongated gland approximately 1 cm in diameter situated in the Sella turcica of the sphenoid bone and it is connected to the base of the brain via the infundibulum or stalk.
➢ Pea shaped structure measuring 1-1.5 cm in diameter
➢ formerly regarded as the master gland because it influences the rest of the endocrine glands; however, the hypothalamus regulates the function of the anterior lobe of the pituitary gland hence this was regarded untrue

Answer 5

Pituitary Gland

Question 6

Pituitary Gland also known as

Answer 6

Hypophysis or Hypophysis Cerebri

Question 7

➢ makes up 75% of the total weight of the gland
➢ arises as an epithelial outgrowth from the roof of the primitive oral cavity known as the Rathke’s pouch
➢ secreting the hormones

Answer 7

Anterior Pituitary

Question 8

Anterior Pituitary also called the

Answer 8

adenohypophysis

Question 9

Divisions of the Pituitary Gland

Answer 9

• Anterior Pituitary
• Posterior Pituitary

Question 10

Hormones secreted by Anterior Pituitary:

Answer 10

o Growth hormones – long bones
o Thyroid stimulating hormone – thyroid gland
o GnRh (follicles stimulating hormone, luteinizing hormone) – testis and ovary
o Prolactin – mammary gland for milk production.
o ACTH (adrenocorticotrophic hormone) – adrenal glands/cortex
o MSH (melanocyte stimulating hormone) – skin

Question 11

➢ derived from downgrowth of nervous tissue from the hypothalamus to which it remains joined by the pituitary stalk
➢ coming from the floor of diencephalon.
➢ It will just store the hormones that will come from hypothalamic nuclei.
➢ does not synthesize hormones. Instead stores and releases two hormones
➢ Secretions from this lobe are produced by the cell bodies of the supraoptic nucleus (produces vasopressin or ADH) and the
paraventricular nucleus (produces oxytocin) of the hypothalamus

Answer 11

Posterior Pituitary

Question 12

Posterior Pituitary also called

Answer 12

neurohypophysis

Question 13

(produces vasopressin or ADH)

Answer 13

supraoptic nucleus

Question 14

(produces oxytocin)

Answer 14

paraventricular nucleus

Question 15

Hormones stored by Posterior Pituitary:

Answer 15

o ADH (antidiuretic hormone, Vasopressin)
o Oxytocin (pitocin)

Question 16

modified neuroglial cells found in the pars nervosa believed to store and release 2 hormones

Answer 16

Pituicytes

Question 17

2 HORMONES IN POSTERIOR PITUITARY

Answer 17

o Pitocin (oxytocin)
o Pitressin or ADH

Question 18

➢ increases water reabsorption at the distal convoluted tubules of the kidneys.
➢ has a vasopressor effect hence also called vasopressin
➢ raises blood pressure by constricting arterioles

Answer 18

Pitressin or ADH

Question 18

➢ Stimulates uterine contraction
➢ stimulates milk ejection (milk “letdown) from the mammary glands in response
➢ to the mechanical stimulation provided by the suckling infant

Answer 18

Pitocin (oxytocin)

Question 19

• a small organ, 6-8 mm long located at the caudal end of the
  diencephalon of the brain.
• consists of cells called pinealocytes
• Hormones secreted: Melatonin derived from serotonin, which may
  promote sleepiness

Answer 19

Pineal Gland

Question 20

Pineal Gland also called

Answer 20

epiphysis cerebri or conarium

Question 21

• a lobulated gland lying in front of the neck at the upper part of the trachea
• there are 2 lobes connected at the midline by the isthmus
• homeostasis
• Contains follicles, which secrete 2 thyroid hormones: thyroxine (T4) and triiodothyronine
  (T3)
  o Actions of the thyroid hormones:
  ➢ increase basal metabolic rate
  ➢ helps maintain normal body
  temperature
• it is formed by various follicles of different sizes and shape lined by simple cuboidal cells containing colloid material containing thyroglobulin
• It lowers blood calcium by inhibiting osteoclast activity, preventing excessive calcium release from bones.

Answer 21

Thyroid Gland

Question 21

follicles secretes 2 thyroid hormones:

Answer 21

thyroxine (T4)
triiodothyronine (T3)

Question 22

between capillaries are dense capillary network supported by

Answer 22

reticular fibers

Question 23

is secreted in response to hypercalcemia (high calcium levels).

Answer 23

Thyrocalcitonin

Question 24

* are small oval endocrine glands closely associated posteriorly with the thyroid gland * supplied by inferior thyroid artery * secretes parathormone, which directly elevate blood calcium levels * usually there are: o 2 superior parathyroid glands o 2 inferior parathyroid glands

Answer 24

Parathyroid Gland

Question 25

if your ____________ will decrease your calcium level, your ____________ will increase your calcium level.

Answer 25

- calcitonin - parathormone

Question 26

small flattened endocrine glands closely applied to the upper pole of the kidneys

Answer 26

Adrenal (Suprarenal) Gland

Question 27

2 Components Of The Adrenal Gland:

Answer 27

* Adrenal Cortex * Adrenal medulla

Question 28

➢ outer and thicker portion ➢ 3 layers of cell: zona glomerulosa, zona fasciculata and zona reticularis ▪ Secretions: o Mineralocorticoids o Glucocorticoids o Androgens

Answer 28

Adrenal Cortex

Question 29

➢ promote libido in females and are converted to estrogen, ➢ also stimulate growth of axillary and pubic hairs in boys and girls and contribute to the prepubertal growth spurt

Answer 29

Androgens

Question 30

(aldosterone and deoxycortisones) ➢ regulate fluids and electrolytes ➢ help adjust blood pressure and blood volume

Answer 30

Mineralocorticoids

Question 31

(e.g. cortisone) ➢ regulate metabolism and resistance to stress

Answer 31

Glucocorticoids

Question 32

➢ Secretes the catecholamines – epinephrine and norepinephrine ➢ Produces effects that enhance those of the sympathetic division of the autonomic nervous system during stress

Answer 32

Adrenal medulla

Question 33

* pistol shaped flattened organ, the head part of which is enclosed by the duodenum, the body at the back of stomach and tail related with spleen * not only exocrine gland but also has important endocrine functions * the endocrine portion is the Islets of Langerhans * the exocrine portion is secretion of enzymes. * pancreatic islets vary in size and most numerous at the tail of the pancreas

Answer 33

Pancreas

Question 33

Cells in the Islets of Langerhans

Answer 33

* Alpha Cells * Beta cells * Delta Cells * F Cells

Question 34

➢ less numerous containing acidophilic granules. ➢ found at the periphery of the islet and secrete glucagon – which increases blood sugar

Answer 34

Alpha Cells

Question 35

➢ found at the center of the islets ➢ it secretes insulin which decreases blood sugar

Answer 35

Beta cells

Question 36

➢ secrete somatostatin, which inhibits secretion of insulin and

Answer 36

Delta Cells

Question 37

➢ secrete pancreatic polypeptide

Answer 37

F Cells

Question 38

* are paired organs lodging in the scrotum are responsible for the production of the male gametes, spermatozoa, and male sex hormones * the endocrine portion is the interstitial cells of Leydig which secrete these androgens: o Testosterone o Dihydrotestosterone o Androstenedione

Answer 38

Testis

Question 39

Its main hormone _____________ regulates production of sperm and stimulates the development and maintenance of masculine secondary sex characteristics such as beard growth and deepening of the voice

Answer 39

testosterone

Question 40

* the follicular cells of the ovarian follicle secrete estrogen and the corpus luteum secretes progesterone * These hormones regulate the female reproductive cycle: o Regulate oogenesis o maintain pregnancy o prepare the mammary gland for lactation o promote development and maintenance of female secondary sex characteristics o placenta also producing a hormone – syncytiotrophoblast, human chorionic gonadotropin (HCG)

Answer 40

Ovaries

Question 41

➢ autoimmune disorder associated with increased circulating levels of thyroid hormones

Answer 41

Grave’s Disease

Question 42

➢ disorder of metabolism and chronic hyperglycemia

Answer 42

Diabetes Mellitus

Question 43

➢ refers to the manifestations of excessive corticosteroids ➢ e.g. Central obesity, moon face, buffalo hump, osteoporosis, hypertension, hyperglycemia

Answer 43

Cushing’s Syndrome

Question 44

➢ disorder caused by the destruction of the adrenal cortices characterized by chronic deficiency of cortisol, aldosterone and androgens causing skin pigmentation

Answer 44

Addison’s Disease

Question 45

Endocrine Gland Diseases

Answer 45

* Grave’s Disease * Diabetes Mellitus * Cushing’s Syndrome * Addison’s Disease

Question 46

secrete estrogen

Answer 46

ovarian follicle

Question 47

secretes progesterone

Answer 47

corpus luteum

Question 48

secrete androgens

Answer 48

Leydig (Testis part)

Question 49

secrete pancreatic polypeptide

Answer 49

F Cells

Question 50

secrete somatostatin

Answer 50

Delta Cells

Question 51

secretion of enzymes.

Answer 51

exocrine portion

Question 52

Secretes the catecholamines

Answer 52

Adrenal medulla

Question 53

secretes parathormone

Answer 53

Parathyroid Gland

Question 54

secretes thyrocalcitonin

Answer 54

Thyroid Gland

Question 55

thyrocalcitonin secreted by

Answer 55

parafollicular cells

Question 56

follicles secrete 2 thyroid hormones:

Answer 56

Thyroxine (T4) Triiodothyronine (T3)

Question 57

secretes melatonin

Answer 57

Pineal Gland

Question 58

secretes several hormones.

Answer 58

Pituitary Gland

Question 59

NEVER BACK DOWN NEVER WHAT!!!!!!!!!!!!!!!?????????????????

Answer 59

NEVER GIVE UP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!