Chapter 13: Endocrine System (Objectives) - A&PII
Compare and contrast cretinism, myxedema, Grave's Disease, and goiter.
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Compare and contrast the two types of the disease Diabetes Mellitus.
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Define the term gonad, list the primary gonads in both sexes, and name the hormones that target those gonads.
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Describe how glucose levels are maintained in the blood. **
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Describe seasonal affective disorder (SAD) in terms of cause, symptoms, and treatment.
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Distinguish between Addison's Disease and Cushing's Syndrome.
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Distinguish between dwarfism, giantism, and acromegaly.
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Explain what is meant by "secondary sexual characteristics," name the hormone that causes their development in both sexes, and list target organs.
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Explain why so few cases of cretinism are seen today.
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Explain why the thymus gland decreases in size as we age.
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Name the gland (hormone) whose production is stimulated by sunlight.
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Name the hormones secreted by the ovary, distinguished which particular portion of the ovary secretes each, and name target organs and actions of those hormones.
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Name the three endocrine glands that are actually divided into two endocrine glands with different functions.
Pituitary Adrenal Thyroid
For each of the major endocrine glands, name the hormone(s) they secrete, identify the target organ if each hormone, and the effect of each hormone. **
Pituitary Gland: Anterior Lobe - Secretes growth hormone (GH), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and prolactin (PRL). Posterior Lobe - antidiuretic hormone (ADH) and oxytocin (OT). start at p. 500 FINISH LATER!
3. Define the term hormone and explain its general characteristics. **
A hormone is a substance secreted by an endocrine gland and transported in the blood, which has actions on its target cells. Characteristics: -Needed in small amounts (potent) -Produces long-lasting effects in the cells they target -Regulates metabolic processes (maintains homeostasis) -Regulated by negative-feedback mechanisms
Define the term gonadotropin, name two gonadotropins secreted by the anterior pituitary gland, and distinguish between them according to their actions.
A hormone that stimulates activity in the gonads (sex cell-producing organ). Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH) FSH: Female = stimulates maturation of an ovarian follicle and ovum Male = stimulates maturation of sperm in the testes LH: Female = causes ovulation Male = causes secretion of testosterone
Describe how calcium levels are maintained in the blood. **
Blood calcium levels are regulated by parathyroid hormone (PTH), which is produced by the parathyroid glands. PTH is released in response to low blood calcium levels. It increases calcium levels by targeting the skeleton, the kidneys, and the intestine.
1. Explain why the endocrine system is so closely related to the nervous system. **
Both systems are very closely related because they exert control over all other body systems through homeostasis. The endocrine system, like the nervous system, is all about communication as cells secrete chemicals that act on other cells. Whereas the nervous system releases neurotransmitter molecules at synapses, the endocrine system releases its characteristic substances, hormones, into the bloodstream.
2. Distinguish between an endocrine gland and an exocrine gland. **
Endocrine gland: "internal secretion" - secretes hormones directly into the bloodstream to act on target cells; are ductless Exocrine gland: "external secretion" - secretions enter tubes or ducts that lead to body surfaces (i.e. sweat); have ducts
Name the two hormones that work together to regulate water and electrolyte levels in the blood and therefore regulate blood pressure. **
Hormones of the Adrenal Cortex: angiotensin and aldosterone
Name the "master" of the anterior pituitary gland. **
Hypothalamus
4. Distinguish between a steroidal and non-steroidal hormone, in terms of composition and action. **
Steroid Hormones: Lipids that include complex rings of carbon and hydrogen atoms; derived from cholesterol; poorly soluble in water; sufficient quantity; can diffuse into cells relatively easily and are able to enter any cell in the body, although only target cells will respond. Chemistry: Sex hormones and adrenal cortex hormones Action: Hormone crosses membranes, hormone combines with nucleus, synthesis of mRNA activated, mRNA enters cytoplasm to direct synthesis of protein. Nonsteroid Hormones: amines, peptides, proteins, and glycoproteins; requires a receptor on the target cell membrane to allow the hormone to enter the target cell. Chemistry: Amines, proteins, peptides, glycoproteins, most hormones Action: Hormone binds to receptor on cell membrane, adenylate cyclase activated, ATP converted to cAMP, cAMP promotes a series of reactions leading to cellular changes.
Explain how the posterior pituitary gland does not produce hormones, but does secrete them. **
The cells that make up the posterior lobe (pituicytes) do not synthesize hormones. However, specialized neurons, whose axon endings enter the posterior lobe of the pituitary, secrete into the bloodstream two important hormones: ADH and OT.
Name the gland that requires iodine to produce most of its hormones. **
Thyroid Gland
