Endocrine physiology

Question 1

what are the characteristics of endocrine glands specifically?

Answer 1

ductless, secrete hormones directly into bloodstream; they secrete internally and hormones only act on target cells

Question 2

what are the characteristics of exocrine glands?

Answer 2

have ducts, secrete hormones into ducts that lead to body surface; secrete externally and deliver to specific site

Question 3

what is a paracrine secretion?

Answer 3

a substance that affects the cell that secreted it as well as nearby cells

Question 4

what is an autocrine secretion?

Answer 4

a substance that affects only the cell that secreted it

Question 5

general characteristics of endocrine system overall?

Answer 5

it’s a chemical communication system, it can take several seconds to an hour to relay info, it’s very precise and will only target cells that respond to specific hormone, hormones have no effect on other cells

Question 6

what are the major endocrine glands?

Answer 6

hypothalamus, parathyroid glands, pancreas, pineal gland, thymus, ovary, testis, kidney, pituitary gland

Question 7

how do hormones create changes?

Answer 7

by altering metabolic processes, they may affect enzymatic activity of a cell, and they may alter the rate of membrane transport of a substance

Question 8

what is upregulation and when does it happen?

Answer 8

an increase in the number of receptors on a target cell, it occurs in response to a decrease in hormone level

Question 9

what is downregulation and when does it happen?

Answer 9

a decrease in the number of receptors on a target cell, it occurs in response to a large amount of hormone level

Question 10

what happens to hormones once they’re done functioning?

Answer 10

they’re secreted through urine

Question 11

what are the 2 types of hormones (chemical composition-wise)? and how do they get to a cell?

Answer 11

1. steroid hormones: lipids, produced from cholesterol; easily diffuse through cell membrane; process: when it gets to target cell (through bloodstream) it diffuses through membrane, and once in it binds in cytoplasm or nucleus (the binding is HRC), HRC activates cell DNA, goes to MRNA, and directs synthesis
2. protein hormones (non-steroid): amino acids, cannot pass through cell membrane; process: when it gets to target cell, hormone binds to a receptor on membrane, HRC happens, which activates adenylate cyclase in the cell, which form cyclic AMP, which brings forth synthesis