{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}


Bio20B_Lecture7 - Bio 20B 7 Endocrine Hormones Continued...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Bio 20B 7: April 24, 2007 Endocrine / Hormones Continued Nervous System Hormones and other chemical signals bind to target cell receptors, initiating pathways that culminate in specific cell responses o Hormones convey information via the bloodstream to target cells throughout the body o Three major classes of molecules function as hormones in vertebrates Water Soluble – generally do not move through membranes Proteins and Peptides Amines derived from amino acids Lipid Soluble – can pass through lipid bi-layer Steroids Signaling Target Sites Using Hormones o Signaling by any of these hormones involves three key events Reception: signal is received on target cell Signal Transduction: secondary signal generated by hormone into the cell Response: might see a change in cytoplasm of cell or gene proliferation Freeman Fig. 47.3 (polypeptides, amino acid derivatives, and steroids targeting cells) What Happens Next? o Binding of a hormone to its receptor initiates a signal transduction pathway leading to response in the cytoplasm or a change in gene expression o The same hormone may have different effects on target cell that have Different hormone receptors Different signal transduction pathways Different proteins for carrying out the response The Human Endocrine System: An Overview o Hypothalamus: located in brain Freeman Fig. 47.4 part 1 Produces Corticotropin-Releasing Hormone ( CRH ): stimulates release from pituitary gland Antidiuretic Hormone ( ADH ): promotes reabsorption of water Oxytocin o Thyroid gland: located on windpipe Freeman Fig. 47.4 part 2 Thyroxine : increases metabolic rate and heart rate; promotes growth Calcitonin : decreases blood Ca + o Adrenal glands: located on top of kidneys Freeman Fig. 47.4 part 3
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Epinephrine : many effects related to short-term stress response: adrenaline Cortisol : many effects related to short-term and long-term stress response, regulation of blood glucose Aldosterone: increases reabsorption of Na + by kidneys o Kidney: an organ Freeman Fig. 47.4 part 4 Produces Erythropoietin (EPO): increases synthesis of red blood cells o Testes Freeman Fig. 47.4 part 6
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 6

Bio20B_Lecture7 - Bio 20B 7 Endocrine Hormones Continued...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon bookmark
Ask a homework question - tutors are online