Endocrine System

Question 1

Hormones

Answer 1

Chemical messengers
Circulate in the blood
Act upon specific target cells
Bring about specific changes in cellular function

Question 2

Exocrine glands

Answer 2

Glandular portion - lines with secretory epithelial cells
Duct portion - lines with simple cuboidal or columnar epithelial cells

Question 3

Exocrine glands function

Answer 3

Secrete non-hormone products via ducts to a target organ, body cavity or tissue surface

Question 4

Endocrine glands

Answer 4

Ductless
Hollow spherical follicles lines with secretory epithelial cells
Each follicle is surrounded by an extensive capillary network

Question 5

Endocrine glands function

Answer 5

Produce hormones that are secreted into interstitial fluid and diffused into the blood where it travels to the target organ, tissue or cell

Question 6

Functions

Answer 6

Co-ordination
Homeostasis
Glandular secretion
Metabolism
Behaviour
Growth and development
Physical appearance
Reproduction
Digestion
Circadian rhythm
Body fluids
Immune response
Mood and emotions
Hunger

Question 7

Hypothalamus

Answer 7

Anterior region of the brain
Below thalamus
Above brainstem
Neurosecretory cell bodies

Question 8

Hypothalamus - function

Answer 8

Co-ordinating homeostatic mechanisms, behaviour patterns and neuroendocrine outputs
Regulates - temperature, fluid volume, growth, pain and pleasure response, hunger and thirst

Question 9

Hypothalamus - releasing and inhibiting hormones

Answer 9

Corticotropin (CRH) - releasing hormone
Thyrotropin (TRH) - releasing hormone
Growth hormone (GH) - releasing hormone
Gonadotropin - releasing hormone
Somatostatin - inhibiting GH and thyroid stimulating hormone (TSH)

Question 10

Pituitary gland

Answer 10

Small pea-shaped gland
Lies at the base of the brain within the pituitary fossa of the sphenoid bone
Suspended from hypothalamus by the infundibulum
Anterior and posterior lobes

Question 11

Pituitary gland - function

Answer 11

Anterior - endocrine organ
Posterior - endocrine organ and nervous functions, intrinsically connected to the hypothalamus

Question 12

Pituitary gland - anterior pituitary gland

Answer 12

75% of total weight
Mass of endocrine glandular epithelial cells forming continuous cords around sinusoid capillary network

Question 13

Pituitary gland - hormones released by anterior pituitary gland

Answer 13

Thyroid-stimulating hormone (TSH) - thyroid hormone synthesis
Adreno-corticotropic hormone (ACTH) - secretion of glucocorticoid hormones
Melanocyte-stimulating hormone (MSH) - influence brain activity
Human growth hormone (HGH) - growth and repair, lipid, carbs and protein metabolism
Follicle-stimulating hormone (FSH) - oestrogen, sperm production
Luteinizing hormone (LH) - progesterone, testosterone
Prolactin (PRL) - milk production and secretion

Question 14

Pituitary gland - posterior pituitary gland

Answer 14

Includes the infundibulum and the pard nervous

Question 15

Pituitary gland - hormones released by posterior pituitary gland

Answer 15

Oxytocin (OT) - uterine contractions, milk release
Antidiuretic hormone (ADH) - reduces urine output

Question 16

Kidneys

Answer 16

Outer cortex - arcuate and interlobular arteries and veins
Inner medulla - renal pyramids
Nephrons

Question 17

Kidney - hormones

Answer 17

Erythropoietin (EPO) - increased RBC production
Calcitriol - absorption of calcium from intestines
Renin - targets angiotensinogen, vasodilation, suprarenal cortex produces aldosterone

Question 18

Ovaries

Answer 18

Located in ovarian fossa close to lateral pelvic wall
Uterine tube covers medial surface
Fimbrae covers lateral surface
Fimbrae - finger-like projections surrounding the opening of the uterine tubes

Question 19

Ovaries - hormones

Answer 19

Oestrogens and progesterone - menstrual cycle, pregnancy

Question 20

Testes

Answer 20

Suspended outside the body in the scrotum
Two testes separated by fibrous tissue called median raphe
Epididymis - tube like structure from, the superior aspect and descends to the tail at the base of the testes, forms the ductus deferens

Question 21

Testes - hormones

Answer 21

Testosterone - secondary sexual characteristics, sperm production

Question 22

Thymus

Answer 22

Lobulated gland
Located in the anterior mediastinum posterior to the sternum and anterior to the trachea
Cortex and medulla
Divided into lobules by connective tissue septa forming enters routes

Question 23

Thymus - hormones

Answer 23

Thymosin
Thymic humoral factor
Thymic factor
Thymopoietin
Promoter the development and maturation of T-lymphocytes

Question 24

Pineal gland

Answer 24

Pea-sized pineal body lies inn the middle of the brain in the midline
Between the two superior colliculi
Associated with regulation of sleep-wake cycle

Question 25

Pineal gland - hormones

Answer 25

Melatonin - during darkness the pineal gland synthesises melatonin. Promote sleep and regulate sleep-wake cycles

Question 26

Thyroid gland

Answer 26

Sits in front of the trachea at the level of C7-T1 Right and left lob which sit either side connected by the isthmus

Question 27

Thyroid gland - hormones

Answer 27

Triidothyronine (T4) - increases BMR, synthesis sodium potassium pump Thyroxine (T3) - body temperature, increase heart rate, blood pressure and contractility, body growth Calcitonin - increase calcium uptake by bones

Question 28

Parathyroid glands

Answer 28

Four, rice-sized Two superior and two inferior Lie on the posterior surface of the lobe of the thyroid gland

Question 29

Parathyroid glands - hormones

Answer 29

Chief cells secrete the hormones Increase calcium in the blood Calcium is removed from the bone tissue into the blood

Question 30

Adrenal gland

Answer 30

Small, yellow, lobular glands that lie superomedial to the kidneys Behind the peritoneum Surrounded by fat Inner medulla and outer cortex Right - pyramid shaped Left - flatter and slightly larger

Question 31

Adrenal glands - function

Answer 31

Regulation of mineral homeostasis Regulation of glucose homeostasis Promote puberty Triggering fight-or-flight response

Question 32

Adrenal glands - cortex hormones

Answer 32

Mineralocorticoids - increase Na+ and water reabsorption into blood, increase blood volume and pressure Glucocorticoids - cortisol, metabolism growth, blood sugar levels, anti-inflammatory Androgens - growth spurts, growth of auxiliary and pubic hair, libido

Question 33

Adrenal glands - medulla hormone

Answer 33

Epinephrine and norepinephrine - enhances effects of nervous system during stress response

Question 34

Pancreas

Answer 34

12-15cm long, leaf shaped Lies horizontally, deep to the stomach Cover in front by peritoneum Endocrine and exocrine Four parts - uncinate process, head, body and tail Central branching duct Ducts join with common bile duct

Question 35

Pancreas - hormones

Answer 35

Glucagon - raise blood glucose Insulin - lowers blood glucose Somatostatin - inhibits insulin and glucagon secretion, suppresses reabsorption of nutrients Pancreatic polypeptide - inhibits somatostatin secretion, suppresses gallbladder contraction