BIO 479 Lecture Notes - Lecture 5: Adrenocorticotropic Hormone, Transfer Rna, Pituitary Gland

• School: University of Maine
• Department: Biology
• Course: BIO 479
• Professor: Rebecca Holberton

Document Summary

Regula(cid:2210)on of homeostasis major endocrine mechanisms. Posi(cid:2210)ve feedback = to "beef up" metabolic or behavioral ac(cid:2210)vi(cid:2210)es above normal levels. Results in a con(cid:2210)nua(cid:2210)on of or increase in signal produc(cid:2210)on. Rese(cid:2224)ng new set point, self-establishing a new homeosta(cid:2210)c level. Storm > cns (cid:336)auditory and vision(cid:337) (cid:336)crh(cid:337) > pituitary (cid:336)acth(cid:337) > adrenal cortex (cid:336)cor(cid:2210)sol(cid:337) > raise level to increase feeding rate. Can only maintain set points for only so long, posi(cid:2210)ve feedbacks mechanisms are only "crutches"! Nega(cid:2210)ve feedback restores metabolic or behavioral ac(cid:2210)vi(cid:2210)es to their original set point. Broad categories of endocrine cells types and products: The signal is decreased and is self-regula(cid:2210)ng. Protein, "protein-pep(cid:2210)de" hormones - amino acids, amines, pep(cid:2210)des, and proteins. "protein hormone" producers: high rates of protein synthesis. Lots of dna transcrip(cid:2210)on, enzymes, mrna, trna ribosomes. Non-protein (cid:336)steroid/steroid-like(cid:337) hormone producers: make proteins (cid:336)enzymes(cid:337) too but Steroids comes from cholesterol ; cholesterol made in liver, gonads, and adrenal cortex. Lots of enzyma(cid:2210)c ac(cid:2210)vity = lots of protein synthesis.