Biology 252Lecture Chapter 20 21 22 23 24 practice questions

The central area of the chest cavity, containing the heart, major blood vessels, trachea, and esophagus.

The space between the parietal and visceral pericardium, filled with fluid to reduce friction during heartbeats.

A clear fluid that lubricates the pericardial membranes, reducing friction during heartbeats.

The outermost layer of the heart, also known as the visceral pericardium, is a serous membrane.

The thickest layer of the heart wall composed of cardiac muscle responsible for the heart's pumping action.

The inner lining of the heart chambers, composed of endothelium, and continuous with the lining of blood vessels.

The groove on the outside of the heart that separates the atria from the ventricles.

The thin-walled upper chambers of the heart, receiving blood from the body and the lungs.

The thick-walled lower chambers of the heart, pumping blood to the rest of the body and lungs.

A valve that controls blood flow between the right ventricle and pulmonary trunk.

A valve that controls blood flow between the left ventricle and the aorta.

The valve between the right atrium and the right ventricle.

The valve between the left atrium and the left ventricle.

The small, tough, fibrous cords that attach to the AV valve flaps and to the papillary muscles to prevent valve prolapse.

The fibrous tissue ring surrounding the valves of the heart, providing structural support and acting as an electrical insulator.

A condition characterized by the death of myocardial cells due to insufficient blood flow, usually caused by a blockage in a coronary artery.

The main artery in the body, carrying oxygenated blood from the left ventricle to the rest of the body.

The circulation of blood through the lungs, where oxygen is picked up and carbon dioxide is released.

The circulation of blood from the heart to the rest of the body, delivering oxygen and nutrients.

The group of specialized cells in the right atrium that initiate the heart's electrical impulses, setting the pace for heartbeats.

A specialized region of the heart's electrical conduction system that slows down electrical impulses before they reach the ventricles, allowing the atria to fully contract, ensuring proper blood flow.

The low-resistance pathways that allow for rapid transmission of electrical impulses between heart muscle cells.

The period of time during which a heart muscle cell cannot be re-stimulated, preventing tetanus (continuous contraction) and ensuring rhythmic heartbeats.

The electrical activity of the heart as recorded by an electrocardiogram (ECG).

The wave on an ECG that represents electrical activity of the atria, indicating atrial depolarization and contraction.

The wave on an ECG that represents electrical activity of the ventricles, indicating ventricular depolarization and contraction.

The wave on an ECG that represents electrical activity of the ventricles, indicating ventricular repolarization.

The contraction phase of the cardiac cycle, where blood is pumped out of the chambers.

The relaxation phase of the cardiac cycle, where the chambers fill with blood.

The volume of blood ejected from the heart with each contraction, a measure of the heart's pumping efficiency.

The total volume of blood pumped by the heart per minute, a measure of the heart's overall efficiency.

The lining of the blood vessels, composed of endothelium, a single layer of epithelial cells that is smooth to reduce friction and prevent blood clotting.

The middle layer of blood vessels, composed of smooth muscle, and responsible for vasoconstriction and vasodilation.

The outermost layer of blood vessels, providing structural support and anchoring the vessel to surrounding tissues.

The specialized capillaries that supply blood to the walls of large arteries and veins, ensuring their own nourishment.

A hardening and thickening of the arteries, often due to plaque buildup, leading to decreased elasticity and reduced blood flow.

The largest veins in the body, draining blood from the head, neck, and upper limbs and returning it to the heart.

The largest vein in the body, draining blood from the lower limbs, abdomen, and pelvis and returning it to the heart.

A network of veins that collects blood from the digestive organs and transports it to the liver, where nutrients are processed and detoxified.

The smallest lymphatic vessels, found throughout the body, responsible for collecting interstitial fluid and returning it to the bloodstream.

The largest lymphatic vessel in the body, collecting lymph from the left side of the body and draining it into the left subclavian vein.

The lymphatic vessel that drains lymph from the right upper limb, head, and neck, and empties into the right subclavian vein.

A type of white blood cell that is responsible for recognizing and destroying specific pathogens.

Small, bean-shaped lymphatic organs located along lymphatic vessels, responsible for filtering lymph and housing lymphocytes.

A small, soft organ located in the upper left quadrant of the abdomen, responsible for filtering blood, storing blood cells, and producing lymphocytes.

A type of immunity that is nonspecific and acts as a first line of defense against pathogens.

A group of proteins found in the blood that are involved in the destruction of pathogens.

A chemical that prevents microbial growth, such as sebum, a substance secreted by sebaceous glands in the skin.

A protein produced by cells in response to viral infections, interfering with viral replication and spreading.

An enzyme found in body fluids that breaks down bacterial cell walls.

A type of white blood cell that engulfs and destroys pathogens, including neutrophils and macrophages.

A type of white blood cell that is the first to arrive at the site of an infection, important for fighting bacteria.

The body's response to injury or infection, involving redness, swelling, heat, and pain.

The movement of leukocytes towards the source of infection, guided by chemical signals released by the infected tissues.

A type of immunity that is specific and involves memory cells, providing a quicker and stronger response to subsequent exposures to the same pathogen.

A type of lymphocyte that directly kills infected cells or cancer cells.

The primary lymphoid organ where T cells mature and become functional immune cells.

A state of unresponsiveness to specific antigens, preventing the immune system from attacking the body's own tissues.

A protein produced by B cells that binds to specific antigens, marking them for destruction.

The process of creating antibodies against a specific pathogen, either through natural infection or vaccination.

The process of transferring pre-made antibodies from a donor to a recipient, providing temporary protection against a specific pathogen.

The exchange of gases between the blood and the body tissues, where oxygen is delivered to the tissues and carbon dioxide is removed.

The process of moving air into and out of the lungs, creating pressure gradients that facilitate gas exchange.

A flap of cartilage that covers the opening to the larynx during swallowing, preventing food from entering the respiratory tract.

The paired folds of tissue located in the larynx that vibrate to produce sound when air passes through them.

The tube that carries air from the larynx to the bronchi.

The tiny air sacs in the lungs where gas exchange takes place between the air and the blood.

The serous membranes that surround the lungs, creating a pleural cavity filled with fluid that lubricates the lungs and allows them to expand and contract smoothly.

The pressure within the pleural cavity, typically lower than atmospheric pressure, which helps to keep the lungs expanded.

A substance produced by cells in the alveoli that reduces surface tension, preventing the alveoli from collapsing.

The presence of air in the pleural cavity, causing the lung to collapse due to the loss of negative pressure surrounding the lung.

The volume of air that can be inhaled and exhaled in one breath, a measure of lung capacity.

The process by which gases move across the respiratory membrane, from an area of high concentration to an area of low concentration.

The protein in red blood cells that binds to oxygen, allowing it to be transported throughout the body.

The chemical reaction that takes place in red blood cells where carbon dioxide reacts with water to form carbonic acid, which then dissociates into bicarbonate ions and hydrogen ions.

The tendency of hemoglobin to hold onto oxygen more strongly in the lungs where oxygen concentration is high and to release oxygen more readily in tissues where oxygen concentration is low.

A reflex triggered by stretch receptors in the lungs that helps to prevent overinflation of the lungs by inhibiting inspiration when the lungs are full.

The major regulator of respiration, monitoring the levels of carbon dioxide, oxygen, and hydrogen ions in the blood to adjust breathing rate and depth to maintain proper blood gas balance.

The part of the brain that controls the switching between inspiration and expiration, helping to create the rhythm of breathing.

The process of chewing food, breaking it down into smaller pieces that are easier to swallow and digest.

The outermost layer of the digestive tract wall, composed of serous membrane, which secretes fluid to lubricate the digestive organs and reduce friction.

The process of moving food through the digestive tract by coordinated muscle contractions.

The muscular sphincter that controls the flow of food from the stomach into the small intestine.

The process of mixing food with gastric juices in the stomach, creating a semiliquid mixture called chyme.

A protein-digesting enzyme secreted by the stomach in an inactive form, pepsinogen, which is activated by the acidic environment of the stomach.

A substance produced by the liver and stored in the gallbladder, which emulsifies fats in the small intestine, aiding in their digestion.

The primary cells of the liver, responsible for a wide range of functions, including bile production, detoxification, and nutrient processing.

The small, glandular structures scattered throughout the pancreas that produce hormones, such as insulin and glucagon, which regulate blood sugar levels.

The three bands of longitudinal smooth muscle in the large intestine that help to create the haustra, the pouches that give the colon its characteristic segmented appearance.

The primary hormone that stimulates the gallbladder to contract and release bile into the duodenum.

The digestive juice produced by the pancreas, containing enzymes that digest all major food groups, including carbohydrates, proteins, and fats.

The process of absorbing nutrients from digested food into the bloodstream.

The major function of the large intestine is to absorb water and electrolytes from the remaining indigestible food matter, forming feces.