Fundamentals Exam 2

Blood Stream

Where endocrine signals travel

Ducts

Where exocrine signals travel

Pancreas

Located under the stomach, secretes insulin (B cells), glucagon (A cells), and somatostatin (D cells)

Pituitary Gland

Master regulator of endocrine system

Peptide Hormones

Hormones made of amino acids, bind outside of the cell because proteins can’t enter the phospholipid bilayer unassisted, sent to lysosomes after binding to be broken down, synthesized as prehormones, stored in granules, cannot be administered orally

Small Protein Hormones

Low concentration in the blood, don’t need a carrier

Large Protein Hormones

Carried by a soluble protein similar to the receptor it binds to in a cell

Growth Hormone

Peptide hormone made of 191 AAs, made of alpha helices and random coils with receptor binding regions

Insulin

Peptide hormone made of 51 AAs, 2 chains joined by disulfide bonds, facilitates uptake of glucose through glucose transport proteins

Preproinsulin

Insulin precursor

Insulin receptor protein

Tetrapeptide that activates tyrosine kinase activity inside the cell membrane, uses GLUT 4 to open glucose pores

Steroid Hormones

Hormones that can enter the cell because of their hydrophobicity, modified versions of cholesterol, synthesized in the adrenal cortex, mostly involving oxidation of NADPH and enzymes from the P450 family of oxidases, can be administered orally

Glucocorticoids

Steroid hormones that increase metabolism of carbs, lipids and proteins, and can also function in immunosuppressive roles, released in response to stress, inhibits bone formation

Mineralocorticoids

Steroid hormones that regulate salt recovery and water volume in the kidneys, as well as raise blood pressure due to ion reabsorption

Androgens/Estrogens

Steroid hormones that aide in the development of sex hormones and supporting pregnancy, cholesterol-based, made in the adrenal glands and gonads after ACTH signaling from the anterior pituitary