BIOL 1201 : Exam Notes
Document Summary
When a platelet contacts a damaged blood vessel, it is stimulated to release thromboxane a2. Thromboxane a2 in turn stimulates ascular spasm and attracts additional platelets to the injured site. Local regulator: only needs stuff from right around the area to fix the problem not the whole body. Chemical signaling in animals: two major systems, endocrine, secreting hormones into the blood, nervous, secreting neurotransmitters into the synapse (junction) Similarities: many hormones are neurotransmitters, some neurons secret hormones, both systems involve cells communicating with other cells. Types of hormones: lipid soluble, bind to cytoplasmic receptors (steroids, water soluble, bind to membrane bound receptors (proteins, figure 45. 6. Speed of response: gene regulation, most often results in a slow response (steroid hormones, figure 45. 8. Direct cytoplasmic response: generally a rapid response (water soluble hormones, figure 45. 7. Endocrine glands: glands that secrete (release) hormones into the blood stream, table 45. 1- all listed. Class produced: figure 45. 4 focus on left hand side.
