BIO211 chapter 17, BIO211 chapter 18

Hormone

Chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another

Target Cell

cells that have receptors for a particular hormone

Ligand

Any molecule that bonds specifically to a receptor site of another molecule.

Hormonal Stimulation

the stimulus for the release of many hormones from their associated endocrine gland is the binding of another hormone

Humoral Stimulation

release of a hormone in response to changes in level of nutrient or ion in the blood

Nervous Stimulation

release of a hormone in response to stimulation by the nervous system

Steroid Hormone

class of hormones that can pass through the cell membrane; can be stored in the body

Biogenic Amine

class of neurotransmitters that are enzymatically derived from amino acids but no longer contain a carboxyl group (such as the neurotransmitters norepinephrine, serotonin, or dopamine)

Protein Hormone

A hormone composed of a long chain of amino acids

Water-Soluble Hormone

a hormone that cannot pass through the plasma membrane on its own, so it influences target cells indirectly, through second messenger systems. Second messenger systems initiate enzyme cascades within the cell that ultimately activate certain enzymes. They include protein and peptide hormones, such as those secreted by the pancreas and pituitary gland

Second Messenger

a molecule that is generated when a specific substance attaches to a receptor on the outside of a cell membrane, which produces a change in cellular function

Local Hormone

hormones that act locally without first entering the blood stream

Autocrine Stimulation

secretions from the cell may attach to the cell's own surface receptors

Paracrine Stimulation

adjacent cells act on each other

Eicosanoid

a class of fatty acids that locally regulate blood vessel vasodilation, temperature elevation, WBC activation, and other physiologic processes involved in immunity

Prostaglandin

A lipid soluble hormone that promotes blood supply to an area

Lipid Soluble Hormones

-steroid and thyroid hormones

-act on intracellular receptors that directly activate genes

-can enter cell

Carrier Proteins

Proteins that bind solutes and transport them across the plasma membrane

Water Soluble Hormones

(all amino acid-based hormones except thyroid hormone)

Act on plasma membrane receptors

Act via G protein second messengers

Cannot enter cell

Intracellular Enzyme Cascade

The binding of the hormone to the receptor results in specific "information" being passed in a signal conduction pathway

Synergistic

describes organisms that are cooperative in action, such as hormones that reinforce each other's activity

Permissive

hormones that allow other hormones to act

Antagonistic

hormones that block the action of others

Hypothalamo-hypophyseal tract

the tract of nerve fibers (axons) that transports antidiuretic hormone and oxytocin from the hypothalamus to the posterior pituitary

Hypothalamo-hypophyseal portal system

portal veins that shunt blood carrying regulatory hormones from hypothalamus to the anterior pituitary

Neurosecretory cells

Neurons of the hypothalamus that secrete neurohormone rather than neurotransmitter

Regulatory hormones

Control release of hormones from anterior pituitary

Releasing hormones

Hypothalamic hormones that stimulate the release of hormones from the anterior pituitary

Inhibiting hormones

hormone secreted by the hypothalamus that can suppress secretion of hormones by the anterior pituitary

Glycogeneolysis

glycogen phosphorylase, breakdown of glycogen into glucose

Gluconeogenesis

the making of glucose from a non-carbohydrate source such as amino acids or glycerol

Glycogenesis

formation of glycogen from glucose

Lipolysis

the breakdown of fats and other lipids by hydrolysis to release fatty acids

Lipogenesis

the process of converting protein into fatty acids

Hyperthyroidism

excessive activity of the thyroid gland

Graves disease

an autoimmune disorder that is caused by hyperthyroidism and is characterized by goiter and/or exophthalmos

Hypothyroidism

underactivity of the thyroid gland

Hashimoto thyroiditis

The most common cause of hypothyroidism.

Cushing syndrome

group of signs and symptoms produced by excess cortisol from the adrenal cortex

Addison disease

chronic syndrome resulting from a deficiency in the hormonal secretion of the adrenal cortex

Stress response

During times of stress, the hypothalamus signals the pituitary gland to produce CRH which in turn signals the adrenal glands to increase the production of cortisol

Diabetes mellitus

a group of metabolic disorders characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both

Diabetes insipidus

hyposecretion of ADH

Type 2 diabetes

typically adult onset progressive disorder in which body cells become less responsive to insulin

type 1 diabetes

typically early childhood onset diabetes in which no beta-cell production of insulin occurs and the patient is dependent on insulin for survival

Hypoglycemia

abnormally low level of sugar in the blood

Hyperglycemia

excessive sugar in the blood; a sign of diabetes mellitus

Arteries

Blood vessels that carry blood away from the heart, oxygenated except for the pulmonary arteries.

Veins

blood vessels that carry blood back to the heart. All veins, with the exception of the pulmonary veins, carry blood containing carbon dioxide and other waste products. The pulmonary veins carry oxygenated blood from the lungs to the heart.

Capillaries

Microscopic vessel through which exchanges take place between the blood and cells of the body

Formed Elements

erythrocytes, leukocytes, platelets

Erythrocytes

red blood cells, carry oxygen

Leukocytes

white blood cells, fight infection

Platelets

blood clotting, thrombocytes

Plasma

Fluid portion of blood

Plasma Proteins

albumins, globulins, fibrinogen in blood plasma

Whole Blood

refers to the mixture of both plasma and formed elements

Buffy Coat

a thin light colored layer of white blood cells and platelets than lie between a top layer of plasma and red blood cells in a centrifuge blood sample

Hematocrit

The percent of the volume of whole blood that is composed of red blood cells as determined by separation of red blood cells from the plasma usually by centrifugation.

Colloid

heterogeneous mixture whose particles never settle

Colloid Osmotic Pressure

pressure exerted by plasma proteins on permeable membranes in the body; synonym for oncotic pressure

Albumin

protein in blood; maintains the proper amount of water in the blood

Globulin

plasma protein; alpha, beta, and gamma (immune) globulins are examples

Fibrinogen

A blood protein essential to blood clotting. The conversion of fibrinogen to its active form (fibrin) is among the final steps in clot formation, and is triggered by thrombin.

Serum

plasma fluid after the blood cells and the clotting proteins have been removed

Regulatory Proteins

proteins involved in the expression of control genes, tropomyosin and troponin

Hemopoiesis

production of blood cells

Hemocytoblast

Stem cell that gives rise to all blood cells, resides in the red bone marrow.

Colony-stimulating factors (CSFs)

Protein that stimulates the growth and proliferation of white blood cells (granulocytes).

Erythropoiesis

production of red blood cells

Leukopoiesis

production of white blood cells

Thrombopoiesis

production of platelets

Hemoglobin

iron-containing protein in red blood cells that carries oxygen for delivery to cells

Heme

iron-based, pigment part of hemoglobin

Erythropoietin

a hormone secreted by the kidneys that increases the rate of production of red blood cells in response to falling levels of oxygen in the tissues.

Transferrin

-Iron transport protein

-Takes Iron from ferritin & transports iron to rest of body

Biliverdin

a bile pigment produced from hemoglobin breakdown

Bilirubin

orange-yellow pigment in bile; formed by the breakdown of hemoglobin when red blood cells are destroyed

Stercobilin

breakdown product of bilirubin that gives feces its brown color

Urobilin

brown pigment formed by the oxidation of urobilinogen; may be formed in the urine after exposure to air

Anemia

A condition in which the blood is deficient in red blood cells, in hemoglobin, or in total volume.

Surface Antigen

cell surface proteins that identify cells to immune system

Type A blood

A antigens and anti-B antibodies

Type B blood

B antigens and anti-A antibodies

Type AB blood

A and B antigens, no antibodies, universal recipient

Type O blood

no antigens, A and B antibodies, universal donor

Rh factor/Antigen D

protein type factor designated as + or -

Agglutination

Clumping of microorganisms or blood cells, typically due to an antigen-antibody interaction.

Hemolysis

the rupture or destruction of red blood cells.

Hemolytic disease of the newborn

This disease occurs in pregnancy if the second fetus is Rh+ while the mother is Rh-.

Hyperbilirubinemia

excessive level of bilirubin (bile pigment) in the blood

Diapedesis

passage of blood cells (especially white blood cells) through intact capillary walls and into the surrounding tissue

Chemotaxis

movement by a cell or organism in reaction to a chemical stimulus

Granulocytes

A group of leukocytes containing granules in their cytoplasm; neutrophils, eosinophils, basophils.

Agranulocytes

A group of leukocytes without granules in their nuclei; lymphocytes, monocytes.

Neutrophils

A type of white blood cell that phagocytizes invading microbes and contributes to the nonspecific defenses of the body against disease.

Eosinophils

Type of WBC is present in increased numbers during an allergic reaction, containing granules that are readily stained by eosin

Basophils

A circulating leukocyte that produces histamine.

Lymphocytes

Two types of white blood cells that are part of the body's immune system

T lymphocytes

form in the thymus and other lymphatic tissue and attack cancer cells, viruses, and foreign substances