Circulation & Cardiovascular Systems [Ch 32] EXAM2

List the functions of the vertebrate circulatory system

Transportation, temperature regulation, blood clotting, and immune function.

Interstitial Fluid

an extracellular fluid that fills the spaces between most of the cells of the body and provides a substantial portion of the liquid environment of the body. Formed by filtration through the blood capillaries, it is drained away as lymph. It closely resembles blood plasma in composition but contains less protein

Three Steps of Adaptive Immune Defenses.

1. Specific response to a pathogen, recognizes pathogen. 2. Mount a primary response. 3. Develop memory cells for next encounter.

Inflammatory Response

4 Cardinal Signs: Redness, Swelling, Heat, & Pain. 1. Injured tissue cells & mast cells release histamine and other chemical mediators, which cause capillaries to dilate & increase blood flow. 2. Resident macrophages & dentritic cells phagocytize pathogens & release cytokines, which stimulate the inflammatory response. 3. Neutrophils & monocytes squeeze through the capillary wall and phagocytize pathogens. 4. Blood clotting walls off capillary and prevents blood loss.

Erythrocyte

A cell that contains hemoglobin and can carry oxygen to the body. Also called a red blood cell (RBC).

Circulatory System

Moves substances to and from cells, usually via heart, blood, and blood vessels. (Flow of blood, carries oxygen, nutrients, & wastes)

Lymphatic Vessels

One way system that begins w/ lymphatic capillaries. -Take up excess tissue fluid. - Lymph: Fluid located w/in Lymphatic capillaries. ~ Lymph flows one way. ~ From a capillary to ever-larger lymphatic vessels. Finally to a lymphatic duct, which returns lymph to a subclavian vein.

Differentiate between open and closed circulatory systems .

Open: Blood vessels plus open spaces, contains Hemolymph, hemolymph is colorless, hemolymph carries nutrients but no oxygen. Ex: Grasshopper (Anthropod) Closed: Blood does not leave the vessels, contains blood, blood consists of cells and plasma, gas exchange and nutrient-for-waste exchange across the capillary walls, blood is red b/c it contains hemoglobin. Ex: Earthworm (Annelids), Squid & Octopuses (Molluscs)

Angina Pectoris

Painful squeezing sensation from myocardial oxygen insufficiency due to partial blockage of a coronary artery [chest pain]

Antibodies [Plasma]

Plasma protein produced by the immune system in response to specific pathogens & other foreign materials.

Albumin [Plasma]

Plasma protein that transports a breakdown of hemoglobin and various lipoproteins transport cholesterol

2 major circular pathways in the human cardiovascular system

Pulmonary Circuit & Systemic Circuit

The two major vascular pathways.

Pulmonary Circuit: Blood flows from the heart to lungs back to heart. Gas exchange occurs [O2 in, CO2 out] Systemic Circuit: Blood from the heart flows to the rest of the body and back to the heart. [Nutrients absorbed from small inestines & delivered wastes removed by filtration in Kidneys]

What keeps our hearbeat regular?

Pulse: expansion & rebound of the artery as the blood is pumped through it.

Ventricle

Pumping chamber; lower chamber of the heart

Diastole

Relaxation period of a heart chamber during the cardiac cycle. [Ventricular Relaxation]

Spleen [Lymphatic System]

Resident T cells and B cells respond to the presence of antigen in blood.

Hemoglobin (RBC)

Respiratory pigment. Contains 4 globin protein chains, each associated w/ heme (iron-containing group). Iron combines loosely w/ oxygen, this way oxygen is carried in the blood.

Red Bone Marrow [Lymphatic System]

Site for the origin of all types of blood cells.

Explain how the cells of animals with no circulatory system acquire nutrients and gases and get rid of wastes.

Some invertebrates (hydras & planarians) their thin body wall makes a circulatory system unnecessary. In hydras, cells are either part of an external layer, or they line the gastrovascular cavity. Each cell is exposed to water and can independently exchange gases and rid itself of wastes. Cells are specialized to complete digestive process. In Planarians, a trilobed gastrovascular cavity branches throughout the small flattened body. No cell is very far from one of the 3 digestive branches, so nutrient molecules can diffuse from cell to cell.

Osmotic Pressure [Capillary Exchange]

Tends to cause water to move from tissue fluid into blood.

Blood Pressure [Capillary Exchange]

Tends to cause water to move in the opposite direction.

Heart Attack

(Myocardial Infarction) Coronary artery becomes completely blocked.

T Cells

- Encounter specific antigen & reproduce -Memory Cell: Future infections - Directly attack infected host cells. *After the infection is gone only the memory cells remain, all the other cells die*

Structure of the Lymphatic System

Tonsils, Red Bone Marrow, Thymus, Spleen, & Inguinal Lymph Nodes.

Functions of the Circulatory System

Transport [connects all parts of the body], Body temperature regulation, Immune system cells [surveillance for antigens, blood clotting proteins.

Trace a drop of blood through the human heart.

-Blood enters the Inferior or Superior Vena Cava and empties into the Right Atrium. (O2-poor) -Passes through the Tricuspid Valve into the Right Ventricle. -Enters the Pulmonary Semilunar Valve into the Pulmonary Trunk. -Enters the lungs to become O2 rich blod. -4 Pulmonary Veins carry (O2-rich) and empty into left Atrium -Passes through the Bicuspid Valve into the left ventricle. -Sends blood through the Aortic Semilunar Valve into the aorta and then throughout the rest of the body.

B Cells

-Encounter specific antigen & start to reproduce. -Makes 2 types of cells ~Plasma Cells: Produce lots of antibodies, current infection protective protein. ~ Memory Cells: Future infection.

Immunity

Ability of the body to protect itself from foreign substances and cells, including disease causing agents.

Atherosclerosis

Accumulation of fatty materials (cholesterol) between the inner linings of arteries.

The overall role of the circulatory system

All animal cells require a steady supply of oxygen and nutrients, and their waste products removed. In most animals these tasks are facilitated by a circulatory system which moves fluid between various parts of the body.

Explain how the exchange of materials and gases exchange of materials occurs in the capillaries

All exchanges happen beneath the cells & capillaries. Capillaries are very narrow and tiny RBCs (must go through single file). Walls of capillaries are very thin to facilitate diffusion [concentration gradient] of nutrients, gases, and wastes. Blood enters a capillary at the arterial end (rich in O2 & nutrients). Osmotic Pressure & Blood Pressure are the primary control movements of fluid. At the arterial end, O/P is lower than B/P H2O exits a capillary at arterial end. Midway, B/P is lower, there is no net movement of H2O. Solutes dissolve according to their concentration gradient. O2 & Nutrients diffuse OUT of the capillary; CO2 & wastes diffuse INTO the capillary. RBC & Plasma remain in capillary. Substances that leave a capillary contribute to tissue fluid. At the Venule end, B/P has fallen even more, O/P is greater & H2O moves into the capillary. Excess tissue fluid is collected by the lymphatic system.

Arganular Leukocytes (WBC)

Also called mononuclear cells, lack obvious granules and include the monocytes and the lymphocytes.

Antigen

Any substance that stimulates the immune system to react.

Open Circulatory System

Arrangement of internal transport in which blood bathes the organs directly, and there is no distinction between blood and interstitial fluid. - Heart pumps hemolymph via vessels - Vessels empty into tissue spaces

Pulmonary Circuit

Circulatory pathway between the lungs and the heart. Gas exchange occurs (O2 in, CO2 out)

Lymphocytes (Adaptive Immune Defenses)

B & T Cells. - Capable of recognizing antigens. - Have antigen receptors on their plasma membrane. - The receptor protein's shape allows it to combine w/ a specific antigen.

Systemic Circuit

Circulatory pathway of blood flow between the tissues and the heart. Blood from the heart to the rest of the body & back to the heart. Nutrients absorbed (from small intestine) & delivered wastes removed by filtration in Kidneys.

2 types of circulatory fluids

Blood (Never leaves blood vessels, no mixing) & Hemolymph (mixture of blood and interstitial fluid)

Closed Circulatory System

Blood is confined to vessels and is kept seperate from the interstitial fluid. - Heart pumps blood to capillaries - Gases and materials diffuse to and from nearby cells - Vessels return blood to heart w/out contact between blood and tissues. - Circulates in 1 direction around a loop.

Vein

Blood vessel that arises from venules and transports blood toward the heart.

Artery

Blood vessel that transports blood away from the heart.

Capillary

Microscopic blood vessel; gases and other substances are exchanged across the walls between blood and tissue fluid.

Inguinal Lymph Node [Lymphatic System]

Located in the groin area. Resident phagocytic cells engulf any foreign debris & pathogens. These phagocytes can then "present" these foreign materials to T Cells in the Lymph Node.

Describe the structure of the vertebrate cardiovascular system.

Closed circulatory system. Consists of a strong, muscular heart in which the atria recieve blood and the muscular ventricles pump blood through the blood vessels. Three kinds of blood vessels: Arteries [carry blood away from the heart], Capillaries [exchange materials with tissue fluid], Veins [return blood to the heart]. Arterioles (small arteries) branch into capillaries. Venules and veins collect blood from the capillary beds and take it to the heart. Venules drain blood from the capillaries, and then join to form a vein.Valves within the veins point, or open toward the heard preventing backflow.

Tonsils [Lymphatic System]

Collection of Lymphoid tissue that respond to pathogens in the pharnyx.

Platelet

Component of blood that is necessary to blood clotting.

Lymphatic System

Consists of lymphatic vessels and the lymphatic organs, transports lymph and lipids, and aids the immune system.

Lymphocytes (WBC)

Contain T-cells and B-Cells which each play a distinct role in adaptive immunity. - Helper T-Cell: Initiates and influences most of the other cell types involved in adaptive immunity. -Cytotoxic T-Cell: Attacks infected cells that contain viruses. -B-cell: Main function is to produce anti-bodies. Each B-cell produces just one type of antibody, which is specific for one type of antigen.

Granular Leukocytes (WBC)

Contains spherical vesicles, or granules, filled w/ enzymes & proteins that these cells use to help defend the body against invading micobes and other parasites.

Systole

Contract period of the heart during the cardiac cycle. [Ventricular Contraction]

Stroke

Cranial arteriole bursts or is blocked by an embolus

Thymus [Lymphatic System]

Lymphoid organ where T cells mature.

Adaptive [Acquired Immunity]

Depends primarily on B & T cells, both capable of binding to and "recognizing" specific antigens. Generate memory against a pathogen [ex:vaccine], Generate primary response, takes 10-14 days to reach peak & get rid of pathogen, Makes memory cells, Secondary exposure to the pathogen peak-response is stronger than primary in 2-3 days

Innate Immune Defense

Do not distinguish 1 type of threat (bacteria, virus, protists, ect.) from another, no memory of the pathogen. Occurs immediately/shortly after an infection occurs. "Same steps every time" - Physical & Chemical Barriers (Keeps everything out) -Inflammatory response -Phagocytes and Natural Killer Cells - Protective proteins [Complement & Interferons]

Atrium

Filling chamber; particularly an upper chamber of the heart lying above a ventricle.

Explain how the heartbeat originates and how the rate & rhythm are controlled.

First the atria contract (while the ventricles relax) and then the ventricles contract (while the atria relax). The rhythmic contraction of the atria and ventricles is due to the internal (intrinsic) conduction system. The SA node initiates the heartbeat about every .85 second by automatically sending out an excitation impluse, which causes the atria to contract. When the impulse reaches the AV node, it signals the ventricles to contract.

Lymph

Fluid, derived from tissue fluid, that is carried in lymphatic vessels.

Atrioventricular node (AV)

Found in the base of the right atrium very near the septum. Relay station, causes a slight pause in the signal from the SA node so that the ventricles are full of blood before they contract.

Sinoatrial node (SA)

Found in the upper dorsal wall of the right atrium. Called the pacemaker b/c it usually keeps the heartbeat regular. They initiate the signal that causes the cardiac cells of the atria to contract nearly simultaneously.

Platelets

Function: Aid clotting Result from fragmentation of large cells in the red bone marrow. When a blood vessel is damaged these cells clump at the site of the puncture and partially seal the leak.

Red Blood Cells

Function: Carry Oxygen throughout the body, remove Carbon Dioxide from body. Small, biconcave disks that at maturity lack a nucleus and contain the respiratory pigment hemoglobin. Manufactured in the red bone marrow of the skull, ribs, vertebrae, and the ends of long bones. The hormone erythropoietin (produced by Kidneys) stimulates production.

White Blood Cells

Function: Fight infections Larger, have a nucleus, lack hemoglobin, & appear translucent. 5 main types- Granular Leukocytes, Neutrophils, Argranular Leukocytes, Monocytes, Lympocytes.

Plasma

In vertebrates, the liquid portion of blood; contains nutrients, wastes, salts, and proteins.

Function of the Lymphatic System.

Includes Lymphatic Vessels & the Lymphoid Organs. Has 3 main functions that contribute to Homeostasis: - Lymphatic Capillaries absorb excess tissue fluid & return it to the bloodstream. -In the Small Intestine, Lymphatic Capillaries [Lacteals] absorb fats in the form of lipoproteins and transport them to the blood stream. - Lymphoid organs and Lymphatic Vessels are sites of production and distribution of Lymphocytes(B & T Cells), which help defend the body against Pathogens.[bacteria & viruses, abnormal cells (cancer cells), foreign proteins (toxins)]

Monocytes (WBC)

Largest, tend to migrate into tissues in response to chronic, ongoing infections, where they differentiate into later phagocytic macrophages.Release growth factors that increase the production of different types of WBC by the bone marrow.

Neutrophils (WBC)

The most abundant and are able to squeeze through capillary walls and enter the tissues, where they phagocytize and digest bacteria.

The components of blood

Two main portions; a liquid portion (plasma) & the formed elements (cells and platelets). Plasma: Contains many types of molecules. Some proteins buffer the blood, maintain osmotic pressure, blood clotting, contains the proteins Albumin & Antibodies. Formed Elements: Red Blood Cells (erythocytes), White Blood Cells (Leukocytes), and Platelets (Thrombocytes)

Arteriole

Vessel that takes blood from an artery to capillaries.

Venule

Vessel that takes blood from capillaries to a vein.

Leukocyte

White blood cells (WBC) that work with the immune system to defend against infectious disease.