Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings PowerPoint ® Lecture Presentations for Biology Eighth Edition Neil Campbell and Jane Reece Lectures by Chris Romero, updated by Erin Barley with contributions from Joan Sharp Chapter 45 Hormones and the Endocrine System

Fig. 45-2a Next to each type of signaling, explain whether it triggers a response in the cells that secrete them, neighboring cells, or cells anywhere in the body. Blood vessel Response (a) Endocrine signaling (b) Paracrine signaling (c) Autocrine signaling

Fig. 45-2b Compare and contrast the two types of signaling. Response (d) Synaptic signaling Neuron Neurosecretory cell (e) Neuroendocrine signaling Blood vessel Synapse Response

Fig Suppose you were studying a cell’s response to a particular hormone, and you observed that the cell continued to respond to the hormone even when treated with a chemical that blocks transcription. What could you surmise about the hormone and its receptor? Signal receptor TARGET CELL Signal receptor Transport protein Water- soluble hormone Fat-soluble hormone Gene regulation Cytoplasmic response Gene regulation Cytoplasmic response OR (a) NUCLEUS (b)

Fig Fill in the missing information. Second messenger Adenylyl cyclase G protein-coupled receptor GTP Protein kinase A

Fig How do steroid hormone receptors directly regulate gene expression? Hormone (estradiol) Hormone-receptor complex Plasma membrane Estradiol (estrogen) receptor DNA Vitellogenin mRNA for vitellogenin

Fig How can the same hormone have different effects on cells? Glycogen deposits  receptor Vessel dilates. Epinephrine (a) Liver cell Epinephrine  receptor Glycogen breaks down and glucose is released. (b) Skeletal muscle blood vessel Same receptors but different intracellular proteins (not shown) Epinephrine  receptor Different receptors Epinephrine  receptor Vessel constricts. (c) Intestinal blood vessel

Fig What hormone is responsible for the reabsorption of the tadpoles’ tail? What role does that hormone play in animals? (a) (b)

Fig Highlight the glands and organs involved in regulating metabolism. Circle glands and organs involved in reproduction. Major endocrine glands: Adrenal glands Hypothalamus Pineal gland Pituitary gland Thyroid gland Parathyroid glands Pancreas Kidney Ovaries Testes Organs containing endocrine cells: Thymus Heart Liver Stomach Kidney Small intestine

Fig Compare and contrast the pathway taken when the blood glucose level is too high or low. Homeostasis: Blood glucose level (about 90 mg/100 mL) Glucagon STIMULUS: Blood glucose level falls. Alpha cells of pancreas release glucagon. Liver breaks down glycogen and releases glucose. Blood glucose level rises. STIMULUS: Blood glucose level rises. Beta cells of pancreas release insulin into the blood. Liver takes up glucose and stores it as glycogen. Blood glucose level declines. Body cells take up more glucose. Insulin

Fig Why is PTTH names a neurohormone? Highlight the gland it triggers and explain the resulting pathway triggered by the production of PTTH. Ecdysone Brain PTTH EARLY LARVA Neurosecretory cells Corpus cardiacum Corpus allatum LATER LARVA PUPAADULT Low JH Juvenile hormone (JH) Prothoracic gland

Fig How are the roles of the hypothalamus, posterior pituitary, and anterior pituitary glands related? Spinal cord Posterior pituitary Cerebellum Pineal gland Anterior pituitary Hypothalamus Pituitary gland Hypothalamus Thalamus Cerebrum

Table 45-1b Pick 1-2 hormones from this table. Highlight the names under the hormone column. Justify why its regulation is critical to human survival.

Table 45-1c Pick 1-2 hormones from this table. Highlight the names under the hormone column. Justify why its regulation is critical to human survival.

Table 45-1d The amount of melatonin produced by the pineal gland is regulated by the amount the light/dark cycles. If melatonin production increases as the evening goes on, why would the pineal gland make more in the winter than in the summer?

Fig How are these hormones different than those in figure 45.17? Posterior pituitary Anterior pituitary Neurosecretory cells of the hypothalamus Hypothalamus Axon HORMONE Oxytocin ADH Kidney tubulesTARGETMammary glands, uterine muscles

Fig Explain why this is a positive feedback mechanism. Suckling Pathway Stimulus Hypothalamus/ posterior pituitary Positive feedback Example Sensory neuron Neurosecretory cell Blood vessel Posterior pituitary secretes oxytocin ( ) Target cells Response Smooth muscle in breasts Milk release +

Fig What two types of signals are triggered by the hypothalamus? Hypothalamic releasing and inhibiting hormones Neurosecretory cells of the hypothalamus HORMONE TARGET Posterior pituitary Portal vessels Endocrine cells of the anterior pituitary Pituitary hormones Tropic effects only: FSH LH TSH ACTH Nontropic effects only: Prolactin MSH Nontropic and tropic effects: GH Testes or ovaries Thyroid FSH and LHTSH Adrenal cortex Mammary glands ACTHProlactinMSHGH MelanocytesLiver, bones, other tissues

Fig Suppose a lab test of two patients, each diagnosed with excessive thyroid hormone production, revealed elevated levels of TSH in one but not the other. Was the diagnosis of one patient necessarily incorrect? Explain. Cold Pathway Stimulus Hypothalamus secretes thyrotropin-releasing hormone (TRH ) Negative feedback Example Sensory neuron Neurosecretory cell Blood vessel Anterior pituitary secretes thyroid-stimulating hormone (TSH or thyrotropin ) Target cells Response Body tissues Increased cellular metabolism – Thyroid gland secretes thyroid hormone (T 3 and T 4 ) –

Fig How are iodine levels related to the formation of a goiter? Normal iodine uptake High level iodine uptake

Compare and contrast the two pathways that regulate blood calcium levels.

Fig a The adrenal medulla and cortex are involved in the stress response. Label the two structures in terms of whether it is involved in short term or long term stress response. Stress Adrenal gland Nerve cell Nerve signals Releasing hormone Hypothalamus Anterior pituitary Blood vessel ACTH Adrenal cortex Spinal cord Adrenal medulla Kidney

Fig b Fill in the missing information. (a) Short-term stress response Effects of epinephrine and norepinephrine: 2. Increased 3. Increased 4. Increased Change in blood flow patterns, leading to alertness and decreased digestive, excretory, and reproductive system activity Adrenal gland Adrenal medulla Kidney

Fig c (b) Long-term stress response Effects of mineralocorticoids: Effects of glucocorticoids: blood volume and blood pressure 2. Possible suppression of immune system * 1. Adrenal gland Kidney Adrenal cortex *prostaglandins promote pain, inflammation, fever, protects stomach lining. NSAIDS inhibit enzymes that produce prostaglandins. So too much NSAIDS = weak stomach lining = ulcer