Anatomy

Question 1

Where is the pituitary found?

Answer 1

In the sella turcica in the body of the sphenoid within the middle cranial fossa

Question 2

What type of tissue is the pituitary gland?

Answer 2

Ant = True epithelial tissue
Post = Neural tissue (extension of the Hypothalamus)

Question 3

How’d you differntiate ant/post pituitary on histology?

Answer 3

Ant stains dark

Post stains light

Question 4

What would you see on close histology of the ant pituitary?

Answer 4

Two different cell types:

• Acidophils (Stain lighter)
• Basophils (stain heavily)

Question 5

What types of cells are acidophils, and what do they make?

Answer 5

• Somatotrophs (GH)

- Mammotrophs (Prolactin)

Question 6

What types of cells are basophils and what do they make?

Answer 6

• Corticotrophs [ACTH & MSH]
• Thyrotrophs [TSH]
• Gonadotrophs [LH & FSH]

Question 7

What hormones are secreted by the post pituitary?

Answer 7

Oxytocin

ADH (Vasopressin)

Question 8

Describe the arterial supply of the pituitary?

Answer 8

ICA
-> Sup & Inf Hypophyseal arteries

Sup -> Hypophyseal portal system

Inf -> Post Pituitary

Question 9

How does the hypothalamus communicate with the pituitary?

Answer 9

Ant - Through hypophyseal portal system

Post - Neurons in the infandibulum

Question 10

Venous drainage of the pituitary?

Answer 10

Hypophysial veins into cavernous sinus

Question 11

Describe the locaiton of the thyroid?

Answer 11

C5-T1

Thyroid cartilae to 6th tracheal ring

Question 12

Where is the thyroid isthmus found?

Answer 12

Between tracheal rings 2 & 4

Question 13

What 3 strap muscles overlie the thyroid?

Answer 13

Omohyoid
Sternohyoid
Sternothyroid
[NOT THE Thyrohyoid]

Question 14

What nerves supply the thyroid & where are they found?

Answer 14

Recurrent Laryngeal Nerve (between trachea/oesophagus)

Sup Laryngeal Nerve (Close to Sup Thyroid Art)

Question 15

Describe the arterial supply of the thyroid?

Answer 15

Sup Thyroid artery - ECA

Inf Thyroid Art - Subclavian

Question 16

Describe the venous supply of the thyroid?

Answer 16

Sup & Middle Thyroid Vein - IJV

Inf Thyroid Vein - Brachiocephalic Vein

Question 17

Where does lymph drain from the thyroid?

Answer 17

Deep Cervical Lymph nodes

Question 18

Describe the histological structure of the thyroid?

Answer 18

Cuboidal epithelial cells arranged in circles forming Follicles

C or Clear cells interspersed

Question 19

What is found within thyroid follicles?

Answer 19

Glycoprotein called colloid bound to the thyroid hormones

Question 20

What do C cells do?

Answer 20

Secrete Calcitonin

Question 21

What 2 hormones do thyroid follicles secrete?

Answer 21

T3 - Triodothyronine

T4 - Thyroxine

Question 22

Where are the parathyroid glands found?

Answer 22

Lateral half of the post surface of each thyroid lobe. External to the fibrous capsule.

Question 23

At what level are the parathyroid glands found?

Answer 23

Sup - Inf border of cricoid

Inf - Inf poles of thyroid

Question 24

Blood supply of parathyroid glands?

Answer 24

Arterial - Inf Thyroid Arteries (Subclavian Art)

Venous - Sup/Middle Thyroid Veins (IJV)

Question 25

Describe the histological appearance of the parathyroids?

Answer 25

Two main cell types: - Chief Cells (numerous and pale staining) - Oxyphil cells (Less common & darker)

Question 26

How are the suprarenal glands peritonised?

Answer 26

Retroperitoneal

Question 27

Embryology of the suprarenal glands?

Answer 27

Cortex - Mesodermal epithelium | Medulla - Neuroectoderm

Question 28

Arterial supply of the adrenal gland?

Answer 28

Inf Phrenic --> Sup Suprarenal Arts Aorta --> Middle Suprarenal Arts Renal Arts --> Inf Suprarenal Arts

Question 29

Venous drainage of the adrenal gland?

Answer 29

Suprarenal Vein Drains into IVC on right and the renal vein on left

Question 30

What are the layers of the adrenal gland and what do they secrete?

Answer 30

Outside in: - Fibrous capsule - Zona Glomerulosa (Mineralocorticoids) - Zona Fasciculata (Glucocorticoids) - Zona Reticularis (Sex Steroids) - Medulla (Catecholamines e.g. epinephrine)

Question 31

How is the pancreas peritonised?

Answer 31

Retroperitoneal | Except tail which is intraperitoneal

Question 32

Describe the arterial supply of the pancreas

Answer 32

Splenic Art gives off pancreatic branches Coelic trunk --> Common hepatic --> Gastroduodenal --> Sup Pancreaticoduodenal Sup Mesenteric --> Inf Pancreaticoduodenal

Question 33

Cell types of the endocrine pancreas?

Answer 33

Alpha - glucagon Beta - Insulin Delta - Somatostatin F - Pancreatic Polypeptide All found in islets of langerhans (lightly stained and non-acinar)