Anatomy flashcard Set 3 (Post Midterm 2 Content)

Endocrine, Repsiratory, GIT, Urinary and Reproductive

Pituitary gland development

Anterior lobe = externally attached during development, an outgrowth of the oral ectoderm which budded off and attached to the posterior lobe

Posterior lobe = direct outgrowth of CNS via stalk (infundibulim)

Anterior pituitary hormones

FSH, LH, GH, TSH, ACTH, Prl and MSH

Posterior pituitary homrones

Vasopressin (ADH) and oxytocin

Hypothalamus connection to anterior pituitary

From nerves which send their messanger hormones in through a primary capillary, which links up via a portal vein to a secondary capillary system within the target site.

Hypothalamus connection to posterior pituitary

Supraoptic nucleus travels down stalk and initiates majority release of Vassopressin; Paraventriculular nucleus travels down stalk and initiates majority release of oxytocin (neurons direclty).

Thyroid gland

Activated by TSH release from anterior pituitary. Within thryoid follicle, thryoglobuline is released and Iodine is added to create T₃ and T₄. These are then released to the blood and help regulate metabolism (stimulate oxygen use, metabolic rate, cellular metabolism and growth/development).

Parafollicular cells (C-cells)

Contained wtihin the thyroid, produce calcitonin (decreases Ca in body fluids, increases Ca in bones)

Parathyroid glands

4 total, placed on each of the 4 corners of the posterior surface of the thryoid gland. Produce parathyroid hormone (decreases Ca in bones, increases Ca in body fluids)

Adrenal cortex hormones

Made of 3 different cells = 3 different hormones produced. Outermost: Mineralcorticoids (aldosterone); Glucocorticoids (cortisol) and Androgens

Chromaffin cells

Post ganglion neuronal cells within the medulla of the adrenal gland that do not contain an axon. Instead, they directly release hormones into the bloodstream (epinephrine and norepinephrine).

Adrenal medulla

Release epinephrine and norepinephrine (fight or flight response).

Pancreas

Made up of exocrine portions which are ducts and inner islets that contain capillaries. The islets are the main endocrine regulator/component and contain 3 different cell types for 3 different hormones

Pancreatic hormones

All within the islet:

1. Alpha cells = glucagon (glucose synthesis, raises blood sugar)

2. Beta cells = insulin (glucose uptake, decreases blood sugar, synthesis of glycogen)

3. Delta cells = Somatostatin (Inhibits secretion of glucagon and insulin)

Diabetes Mellitus

Inability to produce or use inuslin to manage blood sugar levels (causes hyperglycermia and excretion of glucose in the urine). Two types:

1. (10%) = Automimmune disease which destroys isulin secreting (beta) cells. Can be managed with injections of insulin. Called insulin-dependent

2. (90%) = Target cells become less responsive to insulin, correlating with obesity and age. Called insulin independent (insulin is there, the cells just aren’t reacting to it). Managed with diet and exercise.

Pineal gland

Physiological role unclear, secretes melatonin (thought to help with internal clock/sleep cycles).

Lower level vertebrate pineal gland

Closer to the surface of the skin so that it can be impacted/receptive to light changes (bright during day, dark at night etc). Humans have evolved away from this

Thymus gland

Produces T-lymphocytes (maturation).

Kidneys hormones

Erythropoitein (increase RBC production) and renin (increase blood pressure through RAS pathway)

Heart hormones

Atrial natiuretic peptide (decreases blood pressure)

Adipose tissue hormones

Leptin (decreases hunger, feeling of fullness = appetite suppressant)