The Endocrine System

Question 1

glands

Answer 1

secrete hormones

Question 2

hormones

Answer 2

signalling molecules that are secreted directly into the bloodstream to travel to a distant target tissue
at that tissue, they bind to receptors, inducing a change in gene expression or cellular functioning

Question 3

peptide hormones

Answer 3

• made from amino acids
• small as ADH or large as insulin
• derived from larger precursor polypeptides cleaved during post-translational modifications –> Golgi apparatus modifications –> activate hormone and direct it to the correct cellular location –> packaged into vesicles and released via exocytosis
• cannot pass through the plasma membrane => bind to extracellular locations (receptors)
• first messenger -> transmission of second signal (second messenger)
• second messenger