Reading in Saladin - Chapter 17

Reading in Saladin - Chapter 17

• Chapter Overview: Students are instructed to read the entire chapter, excluding Deeper Insight 17.3, and to ensure comprehension of the material using their own words, particularly regarding figures.

Chapter 17 Objectives

• Nervous vs. Endocrine Systems: Match characteristics of nervous and endocrine systems (Table 17.1). Nervous system uses electrical impulses/neurotransmitters, targeting specific cells, acting quickly & locally. Endocrine system uses hormones released into the bloodstream, with widespread and often slower effects.

• Communication Types: Differentiate between paracrine, autocrine, and direct communication (gap junctions). Paracrine action involves signal molecules affecting nearby cells (e.g., histamine and vasodilation). Autocrine action involves a cell affecting itself (e.g., hepcidin inhibiting intestinal iron absorption). Gap junctions facilitate direct communication between cells via biochemical pathways.

• Eicosanoid Production: Detail the steps in eicosanoid production, distinguishing between the actions of NSAIDs and SAIDs. Phospholipid to AA to eicosanoids. SAIDs are non-steroidal, while NSAIDs are steroidal.

• Endocrine Organ Types: Distinguish between endocrine organs (anterior pituitary gland, hypothalamus, etc), neuroendocrine organs(posterior pituitary gland), and secondary endocrine organs (skin, liver, kidney, etc).

• Hormone Classes: Identify examples from each class of hormone (cholesterol derivatives, amino acid derivatives, proteins and peptides). Hormones travel through blood, and some can pass through the phospholipid bilayer.

• Hormone Synthesis: Explain how hormones from each class are synthesized.

• Stimulation of Hormone Secretion: Distinguish, give examples of hormonal, neural, and humoral stimulation of hormone secretion. Hormonal: hypothalamus stimulating anterior pituitary. Neural: preganglionic fibers stimulating adrenal medulla. Humoral: low blood calcium levels stimulating parathyroid hormone (PTH) release.

• Carrier Protein Needs: Identify hormones that require carrier proteins for transport in the blood (e.g., steroid hormones and thyroid hormones), and those that do not (e.g., monoamines and many peptides).

• Target Cell Specificity & Saturation: Note that target cells are specific. Specificity means that a receptor only binds one type of hormone. Saturation occurs when all receptors are occupied, so no additional hormone will have a reaction.

• Hormone Receptor Locations: Identify possible locations of hormone receptors and explain why membranes' characteristics determine location.

• Transduction Process (cAMP): Detail the transduction process using cAMP as a second messenger.

• Transduction Process (IP3/DAG): Outline the alternative transduction process involving IP3/DAG.

• Hormone Receptor Regulation: Understand upregulation (increased sensitivity) and downregulation (decreased sensitivity) of target cell receptors.

• Hormone Interactions: Describe examples of synergistic, permissive, and antagonistic interactions between hormones.

• Hormonal Control Mechanisms: Detail the role of feedback loops in regulating hormonal control (e.g., hypothalamus -> anterior pituitary -> target cells). Negative feedback is often used.

• Hypothalamus-Pituitary Axis: Note the relationship between hypothalamus and pituitary (posterior and anterior), including releasing and inhibiting hormones.

• Hypothalamic Hormones: List and describe the 8 hormones produced by the hypothalamus, noting their target organs and functions.

• Anterior Pituitary Hormones: Name the six hormones synthesized by the anterior pituitary, and the two additional released from the pituitary gland.

• Posterior Pituitary Hormones: Detail the hormones released from the posterior pituitary, noting their stimuli for release, target tissues, and feedback mechanisms.

• Pituitary Gland Regulation: Review the hypothalamus-anterior pituitary axis mechanisms.

• Pineal & Thymus Glands: Briefly highlight specific hormones released by the pineal gland (melatonin) and the thymus (thymopoietin, thymosin, and thymulin).

• Pancreatic Islets: Identify alpha and beta cells and their hormones (glucagon, insulin).

• Diabetes Mellitus: Understand signs/symptoms and pathologies of type 1 and type 2 diabetes, noting the role of beta cells.

• Stress Response (GAS): Detail the stages and components of the General Adaptation Syndrome (alarm, resistance, exhaustion).

• Endocrine Functions of Tissues: Specific endocrine functions of skin, liver, kidneys, stomach, and small intestine, etc are outlined.

• Lab Activity Answers: Answers to selected lab questions are provided in list format.