Endocrine System Flashcards
Exam 4 (Final)
The Endocrine system:
What does it do?
Secretes hormones
The Endocrine system:
What does it control? What does it take part in?
Controls metabolism,
transports substances across cell membrane,
fluid and electrolyte balance,
growth and development, adaptation,
and reproduction
The Endocrine system:
How is hormone production maintained? What does it involve?
Hormone production is maintained by a negative or positive feedback loop involving the hypothalamic–pituitary axis.
Endocrine Dysfunction:
What occurs?
Subnormal hormone production as a result of gland destruction or malformation
Endocrine Dysfunction:
What else can occur?
Hormone excess
Endocrine Dysfunction:
How does production of abnormal hormone occur?
Production of abnormal hormone resulting from gene mutation
Endocrine Dysfunction:
How do hormone receptor disorders result?
Hormone receptor disorders resulting from autoimmune processes
Endocrine Dysfunction:
Disorders of hormone transport or metabolism result in what?
Disorders of hormone transport or metabolism, resulting in increased levels of “free” hormones in the blood
The Hypothalamus and Pituitary Gland
What do they share?
They share two connecting pathways:
The Hypothalamus and Pituitary Gland
They share two connecting pathways: what are they?
- a rich vascular network that connects hypothalamus to anterior pituitary,
- and nerve fibers that link the hypothalamus with the posterior pituitary.
The Hypothalamus and Pituitary Gland:
What do they control?
They control the
thyroid gland,
adrenal glands,
gonads, and
exert control over growth and metabolism.
The Hypothalamus and Pituitary Gland:
What is referred to as the master gland?
Pituitary is referred to as the master gland.
The Hypothalamus and Pituitary Gland:
What is hypothalamus?
Hypothalamus is the coordinating center of the brain.
The Thyroid and Parathyroid Glands
What does the thyroid gland do?
Thyroid gland- Produces, stores, and secretes thyroid hormones T3 and T4
The Thyroid and Parathyroid Glands
Each lobe of the thyroid contains what?
Each lobe of the thyroid gland contains two parathyroid glands.
The Thyroid and Parathyroid Glands
What synthesizes T3 and T4?
Tyrosine (amino acid) and iodide synthesize T3 and T4, stored in the colloid of the follicular cell until needed.
The Thyroid and Parathyroid Glands
What helps transport T3 and T4? Where are they manufactured?
Plasma proteins help to transport T3 and T4 , and are manufactured in the liver.
The Thyroid and Parathyroid Glands
What kind of condition can damage to liver produce?
Damage to liver can produce a condition that resembles hyperthyroidism.
Thyroid and Parathyroid hormones
Thyroid hormones: What are they and what produces them?
The follicular cells of the thyroid glands produce thyroid hormones thyroxine (T4) and triiodothryronine (T3).
Thyroid and Parathyroid hormones
Thyroid hormones: What do T3 and T4 do? What does this lead to?
Both T3 and T4 increase metabolism, which causes an increase in oxygen use and heat production in all tissues.
Thyroid and Parathyroid hormones
Thyroid hormones: What produces calcitonin?
The parafollicular cells produce Calcitonin
Thyroid and Parathyroid hormones
The parafollicular cells produce Calcitonin:
What does calcitonin inhibit?
Inhibits calcium reabsorption in the GI tract
Thyroid and Parathyroid hormones
The parafollicular cells produce Calcitonin:
What does calcitonin increase?
Increases calcium excretion from kidney
Thyroid and Parathyroid hormones
Parathyroid hormone: What is produced by?
Produced by the parathyroid glands
Thyroid and Parathyroid hormones
Parathyroid hormone: What does it promote?
Promotes bone resorption
Thyroid and Parathyroid hormones
Parathyroid hormone: What does it increase?
Increases calcium reabsorption
Increases calcium blood levels
Thyroid and Parathyroid hormones
What does vitamin D do?
Vitamin D acts on intracellular enzymes in intestinal mucosa to increase calcium absorption.
The Pancreas:
Has what kind of functions?
Endocrine functions
Exocrine functions
The Pancreas:
Endocrine functions: What occurs?
The Islets of Langerhans secrete hormones into the blood. They are composed of cell types:
The Pancreas:
Endocrine functions: The Islets of Langerhans secrete hormones into the blood. They are composed of cell types: What are they?
Alpha cells
Beta cells
Delta cells
The Pancreas:
Endocrine functions: The Islets of Langerhans secrete hormones into the blood. They are composed of cell types:
Alpha cells?
Alpha cells which secrete glucagon
The Pancreas:
Endocrine functions: The Islets of Langerhans secrete hormones into the blood. They are composed of cell types:
Beta cells?
Beta cells which secrete insulin.
The Pancreas:
Endocrine functions: The Islets of Langerhans secrete hormones into the blood. They are composed of cell types:
Delta cells?
Delta cells which secrete somatostatin
The Pancreas:
Exocrine functions: What does it involve?
Involves the secretion of digestive enzymes into the duodenum.
The Pancreas:
What do C-peptide levels measure?
C-peptide levels measure the degree of beta-cell activity and can assist in dx of types 1 and 2 diabetes.
The Pancreas:
What do low C-peptide levels indicate? What does this lead to?
Low C-peptide = autodestruction of beta cells; no insulin production = type 1 diabetes
Insulin:
What is it?
Insulin is an anabolic hormone
Insulin:
What is it responsible for?
responsible for blood glucose concentrations and storage of carbohydrates, proteins, and fat
Insulin:
What does it facilitate:
Facilitates use of glucose for energy
Facilitates cellular transport of glucose, amino acids, and fatty acids across cell membranes
Insulin:
What increases the production of insulin?
Elevated plasma levels of glucose increase the secretion of insulin.
Insulin:
What decreases the production of insulin?
Lower levels of glucose decrease insulin output.
Insulin:
Insulin resistance: What is it a characteristic of?
It is a characteristic of type 2 diabetes mellitus.
Insulin:
Insulin resistance: What is it?
It is a physiologic condition in which a person needs more insulin to lower serum glucose effectively than would normally be required.
Insulin:
Insulin resistance: What does this eventually lead to?
Beta cell exhaustion results when the pancreas must keep up with the higher demands for insulin.
Glucose Regulation:
What is involved?
Glucagon
Somatostatin
Pancreatic polypeptide
Glucose Regulation:
Glucagon: What does it do?
Elevates blood glucose levels to enable entry and use by cells of the body by stimulating the secretion of insulin
Glucose Regulation:
Somatostatin: What does it do?
Inhibits the release of insulin and glucagon from the pancreas
Glucose Regulation:
Pancreatic polypeptide:
Has a role in smooth muscle relaxation of the gallbladder
The Adrenal Glands:
What are the two parts?
Adrenal gland cortex
Medulla
The Adrenal Glands:
Adrenal gland cortex: What are the hormones produced by it?
- Mineralocorticoids
- Glucocorticoids
The Adrenal Glands:
Adrenal gland cortex:
Mineralocorticoids- What do they do?
Reabsorption of sodium
Elimination of potassium
The Adrenal Glands:
Adrenal gland cortex:
Glucocorticoids- What do they do?
Responds to stress
Decreases inflammation
Alters metabolism of protein and fat
The Adrenal Glands:
Medulla- produces what hormones?
Epinephrine
Norepinephrine
The Adrenal Glands:
Medulla-
Epinephrine- What does it do?
Stimulates sympathetic system
The Adrenal Glands:
Medulla-
Norepinephrine- What does it do?
Increases peripheral resistance
Endocrine Disorders:
Effect what parts of the body?
Affect all body systems
Endocrine Disorders:
What are they caused by?
Caused by an overproduction or an underproduction of hormones
Endocrine Disorders:
What are signs and symptoms?
Vital signs
Energy level
Fluid and electrolyte imbalances
Heat and cold intolerance
Weight changes
Altered sleep patterns
Thyroid Dysfunction:
What are the most common ones?
The most common are
hyperthyroidism,
hypothyroidism, and
thyroid nodules.
Thyroid Dysfunction:
Hyperthyroidism: its severe form?
Thyrotoxicosis (Thyrotoxic crisis)
Thyroid Dysfunction:
Hypothyroidism: its severe form?
Myxedema coma
Thyroid Dysfunction
What are causes of thyroid dysfunction?
Causes of thyroid dysfunction:
Graves’ disease,
Hashimoto’s disease,
thyroiditis.
Signs and Symptoms of Hypothyroidism:
Lower body:
Pretibial edema
Muscle weakness/cramps
Loss of body hair, dry patchy skin, cold intolerance
Menstrual irregularities
Signs and Symptoms of Hypothyroidism:
Middle body:
Constipation
Slower heart beat,
elevated cholesterol