Endocrine and Cardiovascular Systems Lectures

Flashcards covering vocabulary and key concepts from lectures on the endocrine and cardiovascular systems.

Nonsteroid Hormone

Whole protein; utilizes a second messenger; must fit with a specific receptor site like a lock and key; acts like a first messenger by signaling another hormone to go do what it needs to do.

Steroid Hormone

Receptor sites are in the cell's nucleus; small, fat-soluble, enters the target cell through its membrane and attaches to its receptors in the nucleus.

Positive Feedback Mechanism

Amplifies what the body is already doing; an example is oxytocin during labor.

Negative Feedback Mechanism

The body creates high or low hormone levels to restore balance; for example, when blood sugar goes up, the pancreas releases insulin to bring it down.

Prostaglandins

Found in a wide variety of tissues; influences cAMP production; controls activities of widely separated organs and neighboring cells; affects respiratory rate, blood pressure, GI secretions, and inflammation.

Pituitary Gland

Located below the hypothalamus; made up of an anterior part (adenohypophysis) and a posterior part (neurohypophysis).

Adenohypophysis (Anterior Pituitary)

Releases hormones such as thyroid-stimulating hormone (TSH), luteinizing hormone (LH) which acts with FSH, adrenocorticotropic hormone (ACTH), and growth hormone.

Neurohypophysis (Posterior Pituitary)

Releases antidiuretic hormone (ADH) and oxytocin (OT).

Thyroid Gland

Located in the neck just below the larynx; releases hormones such as T3, T4, and calcitonin, which affects calcium levels in the blood and bone.

Parathyroid Gland (PTH)

Increases the concentration of calcium in the blood, having the opposite effect of calcitonin from the thyroid gland.

Adrenal Gland Hormones

Sits right on top of the kidneys; has two separate glands: adrenocortex (outer part) and adrenomedulla (inner part), each releasing different sets of hormones.

Gluconeogenesis

The process in liver cells that convert amino acids to glucose.

Estrogen

Secreted from the ovarian follicle; involved with breast development, external genitalia, and the menstrual cycle.

Testosterone

Interstitial cells secrete it into the blood, producing sperm, beard growth, changes in voice, and muscular development.

Thymus Gland

Assists with the immune system.

Pineal Gland

Helps with the circadian cycle and releases melatonin to help with sleep.

Blood Plasma

The liquid part of the blood containing chemicals needed by the cells, nutrients, oxygen, and salts.

Globulins

Include antibodies that help protect us from infection circulating in the plasma.

Albumin

Helps retain water in the blood by osmosis and is administered IV as a plasma volume expander.

Platelets

Thrombocytes

Granular Leukocytes

Neutrophils, eosinophils, and basophils; they all help fight infections.

Myeloid Tissue

Red bone marrow.

Red Blood Cells (RBCs)

Biconcave disc in shape; has no nucleus; surface area allows more oxygen to be carried.

Anemia

A condition where the body doesn't have enough healthy red blood cells or they don't function properly, caused by inadequate numbers of red blood cells, deficiency of normal hemoglobin, or low levels of hemoglobin.

Heart Location

Located in the thoracic cavity between the sternum and in front of the body's thoracic vertebrae.

Coverings of the Heart (Pericardium)

The inner layer is called the visceral pericardium (or epicardium), and the outer layer is the parietal pericardium.

Atrioventricular Valves

The valve on the right is called the tricuspid valve, and the valve on the left is called the bicuspid or mitral valve.

Pulmonary Valve

The pulmonary artery allows blood going to the lungs to flow out of the right ventricle during systole, preventing it from flowing back into the ventricle during diastole.

Aortic Valve

Blood flows out of the left ventricle up into the aorta but prevents backflow.

Chordae Tendineae

String-like structures that attach to the edges of the leaflets of the AV valves and to the wall (help to open and close.

S1 Heart Sound

Valves are closed during ventricular systole.

S2 Heart Sound

SL (Semilunar) valves are closed during ventricular diastole.

Pulmonary Circulation

Takes deoxygenated blood to the lungs for oxygenation.

Coronary Circulation

Gives heart muscle oxygenated blood and comes straight off the aorta. Includes the right coronary, and left anterior descending arteries

MI

Myocardial Infarction; heart attack

Electrical Conduction Pathway

Sinoatrial (SA) node, AV node, AV bundle (bundle of His), and subendocardial branches (Purkinje fibers).

P Wave

Occurs with depolarization of the atria.

QRS Complex

Depolarization of the ventricles.

T Wave

Electrical activity generated by repolarization of the ventricles.

Arteries

Pumps arterial blood from the heart all over the body. Composed of outer layer (tunica externa), middle layer (tunica media), and inner layer (tunica intima).

Veins (Venous System)

Joined together to carry blood to the right atrium after it is circulated.

Mechanisms for Venous Return

Strong beating heart, adequate arterial blood pressure, valves in the veins, pumping action of skeletal muscle, and changing pressures in the chest cavity caused by breathing.

Hepatic Circulation

Veins from the spleen, stomach, pancreas, gallbladder, and intestines do not pour their blood directly into the inferior vena cava, instead their blood goes into the hepatic portal vein