Hormones - o catecholamines - secreted by adrenal medulla,...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Hormones hormone - regulatory chemical secreted by endocrine gland only target cell can respond to hormone (but blood carries hormone throughout the body) neurotransmitter - only diffuse a short distance, but may be chemically similar to hormones o effects the postsynaptic neuron o neurohormone - chemicals secreted from neurons into blood o some molecules work as both neurotransmitters and hormones targets ligand-gated receptors on target cells o messages sometimes relayed through 2nd messenger, magnified through enzyme cascade paracrine regulation - using chemicals as local regulators in an organ pheromone - chemical released into the environment o used as communication between animals types of hormones - polypeptides - chains of amino acids (never more than 100) o insulin, ADH glycoproteins - polypeptides (w/ over 100 amino acids) attached to carbohydrate o FSH, LH amines - derived from tyrosine/tryptophan amino acids
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: o catecholamines - secreted by adrenal medulla, includes adrenaline/noradrenaline o melatonin, thyroid hormone steroids- lipids derived form cholesterol o sex steroids - secreted by testes, ovaries, placenta, adrenal cortex o corticosteroids - secreted only by adrenal gland lilophilic hormones - fat soluble, includes steroids/thyroxine lilophobic hormones - water soluble, all other hormones most releases of hormones controlled by the brain hormones that enter cells- lipophilic hormones easily enter cells (can pass plasma membrane) either finds receptor in cytoplasm or inside nucleus (either way, eventually reaches nucleus) hormone response elements - DNA segments binding to hormones hormones that do not enter cells- lipophobic hormones cant pass plasma membrane have to bind to receptors 2nd messenger needed within the cell to get the reactions started...
View Full Document

Ask a homework question - tutors are online