1 / 38

Chapter 10 The Endocrine System

Summary. IntroductionTwo types of glands and their secretionsRegulation of hormone secretionEndocrine glands, secretions and actions. Introduction. The nervous system provides rapid, brief control through fast traveling nerve impulses.The endocrine system provides slower, long-lasting control via hormones..

spencer
Download Presentation

Chapter 10 The Endocrine System

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

    1. Chapter 10 – The Endocrine System The secondary communication system

    2. Summary Introduction Two types of glands and their secretions Regulation of hormone secretion Endocrine glands, secretions and actions

    4. Introduction The nervous system provides rapid, brief control through fast traveling nerve impulses. The endocrine system provides slower, long-lasting control via hormones.

    5. Glands and Secretions 2 types Exocrine – Endocrine –

    6. Glands and Secretions 2 types cont’d Endocrine glands cont’d – hormones travel in the blood to a “target organ/cell”. How do hormones know which cell is the target cell?

    7. Regulation of Hormone Secretion Negative feedback – highly specialized homeostatic mechanism. The primary type of regulatory mechanism. Positive feedback – uncommon mechanism that amplifies changes rather than reversing them.

    8. Endocrine Glands Pituitary gland – about the size of a pea located deep in the cranial cavity in a small depression of the sphenoid bone – sella turcica. Considered one of the most important glands in the body because its secretions control other endocrine glands. (It is controlled by the hypothalamus.) Pituitary stalk (infundibulum) attaches the pituitary to the hypothalamus. 2 parts – anterior and posterior pituitary

    10. Endocrine Glands - Pituitary Anterior pituitary (adenohypophysis) secretes: Thyroid stimulating hormone (TSH) – Adrenocorticotropic hormone (ACTH) –

    11. Endocrine Glands - Pituitary Anterior pituitary Follicle Stimulating hormone (FSH) - stimulates the primary ovarian follicles in the ovary to start growing and maturing in females. Lutenizing Hormone (LH) – causes ovulation in females. In males it (interstitial cell stimulating hormone) stimulates interstitial cells in the testes to develop and secrete testosterone. Prolactin – stimulates breast development for lactation and milk production.

    12. Endocrine Glands - Pituitary Anterior pituitary Melanocyte stimulating hormone (MSH) – causes a rapid increase in the formation of melanin or pigment granules in specialized skin cells. Growth Hormone (GH) –

    14. Endocrine Glands - Pituitary Anterior pituitary Growth hormone Hyposecretion in early years – dwarfism Hypersecretion in early years – giantism Hypersecretion in adults - acromegaly

    15. Endocrine Glands - Pituitary Posterior pituitary (neurohypophysis) – structure is nervous tissue. Stores and secretes two hormones produced in the hypothalamus: Antidiuretic hormone (ADH) – acts to decrease urine volume by increasing the reabsorption of water by the kidney. The water enters the blood stream and increases blood volume.** Oxytocin –

    17. Endocrine Glands - Thyroid Located in the neck just below the larynx. Secretes 3 hormones: *T3 and T4 both stimulate cellular metabolism. Cellular metabolism – chemical processes that result in growth, generation of energy, elimination of wastes, etc.

    20. Endocrine Glands - Thyroid Hormones T3 and T4 - abnormalities Grave’s Disease – Hyperthyroidism – over secretion of thyroid hormones; dramatically increases metabolism, weight loss, appetite, nervous irritability, exopthalmus (bugged eyes), ?goiter.

    21. Endocrine Glands - Thyroid Hormones T3 and T4 abnormalities Hypothyroidism – under secretion of thyroid hormones (can be caused by lack of iodine intake). Low metabolic rate, weight gain, decreased mental and physical vigor, hair loss, goiter (enlargement of thyroid).

    22. Endocrine Glands - Thyroid Hormones Calcitonin – decreases the amount of calcium in the blood by inhibiting the breakdown of bone (prevents hypercalcemia)

    23. Endocrine Glands – Parathyroid Glands Located on the posterior surface of the thyroid; usually 4 in number. Hormone is parathyroid hormone which prevents hypocalcemia.

    25. Endocrine Glands – Adrenal Glands Sit on the superior surface of the kidneys; actually two glands in one. Adrenal cortex – outer part secretes hormones called corticoids: Androgens – weak male hormones (no effect in adult males but ? increase sex drive in females). Mineralocorticoids (aldosterone) – help control the amount of mineral salt in the blood, primarily Na.

    27. Endocrine Glands – Adrenal Glands Adrenal Cortex – hormones Glucocorticoids – 3 functions: Help maintain normal blood glucose levels through increased gluconeogenesis (conversion of amino acids and fatty acids to glucose in the liver). Essential in maintaining normal blood pressure. With hormones from the adrenal medulla provide and anti-inflammatory effect.

    29. Endocrine Glands – Adrenal Glands Adrenal cortex – hormones Hypersecretion of glucocorticoids = Cushing’s Syndrome, moon face, buffalo hump; often caused by a tumor. Hyposecretion of glucocorticoids = Addison’s disease, muscle weakness, low blood sugar, nausea, anorexia, weight loss.

    30. Endocrine Glands – Adrenal Glands Adrenal Medulla – secretes epinephrine and norepinephrine (catecholamines).

    32. Endocrine Glands – Pancreas Extends from the curve of the duodenum to the spleen. Has exocrine and endocrine functions Endocrine part consists of clumps of cells called Islets of Langerhans or pancreatic islets.

    33. Endocrine Glands – Pancreas Islets contain 2 types of cells Alpha – secrete a hormone called glucagon that accelerates the conversion of glycogen to glucose (glycogenolysis) in the liver. Beta – secrete insulin which lowers blood sugar. Glucagon and Insulin are antagonists.

    35. Endocrine Glands – Pancreas Blood sugar Normal 80-120 mg/dl Hypoglycemia Hyperglycemia Diabetes Type I – Type II –

    36. Endocrine Glands – Ovaries Female sex glands contain 2 different glandular structures: Ovarian follicle – secretes estrogen in response to stimulation by FSH. Corpus luteum – secretes mainly progesterone (some estrogen) in response to LH.

    37. Endocrine Glands – Testes Interstitial cells of the testes secrete testosterone.

    38. Endocrine Glands – Thymus Located in the chest (mediastinum between the lungs); functions to provide immunity; secretes hormone called Thymosin and others that help T-lymphocytes (immune cells) develop.

    39. Endocrine Glands – Pineal Gland Located in the brain; produces melatonin associated with normal sleep/wake cycles. This gland is the body’s internal clock.

More Related