What is a Hormone?
Substance produced in one part of the body(endocrine system), passes through the bloodstream and is carried to other distant organs or tissues, where it acts to modify their structure or function.
What causes an increase in blood calcium levels?
Parathyroid hormone: controls the distribution of calcium and phosphate in the body. High levels of the hormone cause transfer of calcium from bones to the blood.
What are the symptoms of diabetes mellitus?
Increased Thirst, Frequent urination, Fatigue and weakness, Blurred vision, Abdominal pains, Nausea and vomiting, Sudden weight loss or gain, Skin infections like abscess, pimples, Impotence, Fluid retention (especially in legs and feet), Chronic itching, Poor healing of skin wounds, Decreased tolerance to cold, Increased heart rate, Dry scaly skin, Numbness of fingers and toes, Extreme hunger pangs, Hot and sweaty with clammy perspiration Heart tremors and palpitations, Apprehensive with no obvious reason, Nervousness, Disoriented, confused, inability to concentrate, Frequent headaches, dizziness,
Where are oxytocin and ADH stored?
The posterior lobe of the pituitary gland
What is the function of oxytocin?
Causes contraction of the uterus during labor and stimulates milk flow.
What is the function of ADH(Anti-diuretic hormone)?
Stimulates re-absorption of water by the kidney tubules to cause concentration of urine and also it stimulates contraction of muscular tissues of the capillaries and arterioles, raising the blood pressure.
What hormones are secreted by the adrenal medulla?
Epinephrine and nor-epinephrine
What does epinephrine regulate?
Helps regulate the sympathetic part of the autonomic nervous system.
What is the function of epinephrine?
In a moment of fight or flight, epinephrine is a powerful vaso-pressor that increases heart rate, cardiac output and blood pressure. It also increases the release of glucose from the liver for increased feeling of muscular strength.
What is nor-epinephrine?
A catecholamine that is the neurotransmitter of most sympathetic post-ganglionic neurons and also of certain tracts in the CNS.
When is nor-epinephrine released?
It is released in response to sympathetic stimulation primarily in response to hypo-tension.
What does nor-epinephrine cause in the human body?
It produces vaso-construction, an increase in heart rate, and elevation of blood pressure.
What hormones are secreted by the adrenal cortex?
The adrenal cortex produces a number of different corticosteroid hormones(Mineralocorticoids, Glucocorticoids, Androgens)
What mineralocorticoids(aldosterone) regulate?
they help regulate salt and water balance in the body.
What is the function of glucocorticoids(cortisol,cortisone)?
They are essential for the utilization of carbohydrates, fat and protein by the body and for normal response to stress.
What are androgens?
Any steroid hormone that promotes male secondary sex characters.
What are the cells of the pancreas?
Alpha cells, beta cells, and delta cells.
What hormone is secreted by the alpha cells?
What hormone is secreted by the beta cells?
secrete insulin and amylin
What hormone is secreted by the delta cells?
secrete somatostatin, and gamma cells, which secrete a polypeptide of unknown function.
What is the function of glucagon?
Causes an increase in blood sugar level and thus has an effect opposite to that of insulin.
What is the function of insulin?
Important in regulating the amount of sugar in the blood. Is stimulated by a high concentration of blood sugar. Lack of this hormone cause diabetes.
What is the function of somatostatin?
In the pancreas it suppresses secretion of insulin and glucagon.
What are the layers of the heart?
pericardium, myocardium, endocardium.
What is the function of the pericardium?
Keeps the heart contained in the chest cavity, prevents the heart from overexpanding when blood volume increases and limits heart motion.
What does the pericardium surround?
The heart and the proximal ends of the aorta, vena cava, and the pulmonary artery.
What does the pericardium consist of?
It consist of a triple-layered fluid-filled sac that surrounds the heart. The Fibrous Pericardium, Serous Pericardium(Parietal Pericardium, Visceral Pericardium).
The outermost layers of the pericardium is...
What is the function of the fibrous pericardium?
Being a strong layer of connective tissue it acts as a tough outer coat that holds the heart in place and keeps it from overfilling with blood.
How many layers does the serous pericardium have?
Two Parietal Pericardium and Visceral Pericardium
What does the fluid in the parietal pericardium do?
This small amount of fluid, the pericardial fluid, acts as a lubricant to allow normal heart movement within the chest. Avoids friction
What other name does the visceral layer have?
Epicardium which lies on the heart and is considered a part of the heart wall.
What does the myocardium consist of?
consists mainly of cardiac muscle cells, called bundles, squeeze blood through the heart in the proper directions: inferiorly through the atria and superiorly through the ventricles.
What is the endocardium?
is an innermost, thin, smooth layer of epithelial tissue that lines the inner surface of the heart chambers and valves.
Where is Sinoatrial Node(SA) located?
is a specialized bundle of neurons and is in the upper part of the right atrium of the heart(Right chamber).
What is the function of the SA?
To originate muscle contractions and regulate the rhythm of the heart and also it originates the electrical impulse for the entire conduction system of the heart. Dictates the heart rate at 70 - 80 beats per minute when the body is at rest.
What causes the lub sound in the heart?
sound is produced when the atrioventricular valves in the heart close.
What causes the dup sound in the heart?
sound is created when the semilunar valves (aortic and pulmonary) close.
Why is the dup sound louder than the lub sound in the heart?
because the cusps of the semilunar valves are more rigid than the atrioventricular valves (mitral and tricuspid).
What occurs during systole?
is when the heart contracts and the blood is pushed out of the heart into the arteries. The auricles contract anti-phase to the ventricles and chiefly serve to optimally fill the ventricles with blood.
What occurs during diastole?
is when the heart relaxes and blood fills the ventricles
What is the difference between veins and arteries?
Arteries are the carriers of red oxygenated blood (exception: pulmonary arteries which carry de-oxygenated blood from the heart to the lungs). Whereas veins carry bluish-red de-oxygenated blood (exception: pulmonary veins which carry oxygenated blood from the lungs to the heart)
What are the main characteristics of arteries?
1) they are able to withstand the immense pressure of the blood as it is forced out of the heart directly.
2) it flows fast, in spurts, reflecting the rhythmic pumping action of the heart because its under great pressure.
3) have thick and elastic muscular walls which the resistance to pressure comes largely from thee elastic fibres.
4) have no valves.
What are the main characteristics of veins?
1) carry blood towards the heart.
2) the blood is not under great pressure, it flows more slowly and smoothly.
3) have relatively thin and slightly muscular walls.
4) have internal valves along their length to prevent back flow of blood. These valves are folds of the inner walls, shaped like half-moons(semi-lunar)
What is the difference between atherosclerosis and arteriosclerosis?
Arteriosclerosis, also known as hardening of the arteries, occurs when the arterial walls thicken and then harden as calcium deposits form. If the coronary vessels are affected, this is known as coronary artery disease. Atherosclerosis is another type of hardening of the arteries in which lipids, particularly cholesterol, build up on the side arterial walls.
What happens during ventricular contraction?
This is when the ventricles contract and eject blood into the lungs (from the right ventricle) or into the systemic circulation (from left ventricle). Forcing blood into the aorta and pulmonary artery.
What does the P waves indicate in a normal electrocardiogram?
What is Atrial Depolarization?
is the spread of impulse from the SA node over atria. Depolarization is when contraction happens, the electrical impulse is what drives the contraction, so it's the electricity firing (depolarizing) that makes the heart contract.
What are the names of all the heart valves?
atrioventricular valves(tricuspid, mitral)
separating the atria from the ventricles; and semilunar valves(aortic, pulmonary) separating the ventricles from their great vessels.
What do the atrioventricular valves consist of?
consist of a flap of endothelium with a core of connective tissue.
What does the tricuspid valve prevent?
prevents backflow of blood from the RV to the RA, the tricuspid valve contains 3 flaps.
What does the mitral valve(bicuspid) prevent?
prevents backflow from the LV to the LA, It contains 2 valve flaps.
What does the chordae tendinea attach to?
Attach to the valve flaps are strings of collagen and attach to papillary muscles in the ventricle wall.(note: chordae tendinea have no association with the semilunar valves).
What does the aortic semilunar valve prevent?
prevents backflow from the aorta into the LV
What does the pulmonar semilunar valve prevent?
prevents backflow from the pulmonary trunk into the RV.
What are the vessels of the heart?
Arteries(aorta,descending aorta, pulmonary trunk artery, right pulmonary artery, left pulmonary artery). Veins(Superior vena cava, inferior vena cava, right pulmonary veins, left pulmonary veins)
Which are the heart arteries(toward)?
aorta,descending aorta, pulmonary trunk artery, right pulmonary artery, left pulmonary artery.
Which are the heart veins(away)?
superior vena cava, inferior vena cava, right pulmonary veins, left pulmonary veins.
What does plasma contain?
plasma proteins, nutrients, electrolytes, respiratory gases, hormones, buffers and wastes.
What are the main plasma proteins?
Albumin(maintain osmotic pressure), Globulins(antibodies), prothrombin and fibrinogen(both are blood clotting).
What is involved in the final step of blood clotting?
Fibrin, an insoluble protein forms an intricate network of threadlike structures called fibrils and causes the blood plasma to gel. The blood cells and plasma are enmeshed in the network of fibrils to form the clot
How is carbon dioxide transported in the blood?
An enzyme in RBCs called carbonic anhydrase causes CO2 and water to convert to carbonic acid. Since carbonic acid is a weak acid it qucikly dissociates into a hydrogen ion and a bicarboate ion. The hydrogen ions bind to the hemoglobin while the bicarbobate ions is transported in the blood.
How is oxygen transported in the blood?
Hemoglobin is the compound in red blood cells that carries oxygen from the lungs to body cells. The oxygen combines readily with the ion in hemoglobin, and hemoglobin can carry more than twenty times its own volume in oxygen. After releasing oxygen to the cells, hemoglobin collects carbon dioxide and carries it to the lungs where it is exhaled.
What do oxygen and CO2 bond with to be carried through the blood?
Both oxygen and carbon dioxide bond with haemoglobin. Oxyhaemoglobin is carried from the lungs, carboxyhaemoglobin is carried to the lungs
What does damage to platelets cause?
What is hilum?
that part of the lung that is not covered by pleura and through which blood vessels, bronchi, nerves and lymphatics enter and leave the lung.
What is the serous membrane called that is in contact with the lung?
The pleura of the thorax(pleura membrane) are the serous membranes which enclose the upper chest cavity.
What is the function of the pleura membrane?
it enclose the lungs and protect them from friction against the wall of the thorax.
How many layers does the pleura membrane consist of?
It is formed of two layers: the visceral and parietal pleura between which is lubricated by serous fluid.
What does the parietal pleura layer connect to?
The parietal pleura is the exterior layer of this pulmonary pleural sac, which connects to the thorax wall, the mediastinal membrane, and the diaphragm muscle.
How much carbon dioxide is transported in the blood as bicarbonate?
67% of CO2
What causes respiratory acidosis?
by excessive buildup of carbon dioxide in the body that disrupts the pH balance causing the blood to go overly acidic(rise of CO2 in the Blood)
What is the tidal volume?
Where are the inspiratory and expiratory centers located?
in the medulla and pons that coordinate respiratory movements.
What does surfactant do in lungs?
reduces the surface tension of fluid in the lungs and helps make the small air sacs in the lungs (alveoli) more stable.(keeps from collapsing when exhaling).
What kind of epithelium lines the trachea?
Pseudo stratified ciliated columnar.