Human Biology Test 3 Chapters 11, 12, 14

Chapter 12 What are precapillary sphincters and what are their functions?

-A ring of smooth muscle called precapillary sphincter surrounds the capillary where it branches off the arteriole and regulates blood flow into it. -Precapillary sphincters act as valves that open and close the capillary beds.

Chapter 11 What are the three major types of plasma proteins and the roles they perform?

-Albumins: make up more than half of the plasma proteins, most important in bloods water balancing ability-osmosis -Globulins: Have a variety of functions. transports lipids and fat-soluble vitamins. Others are antibodies that provide protection against many diseases. -Clotting proteins: Fibrinogen, allows blood to clot.

Chapter 14 What are alveoli, surfactant and respiratory distress syndrome?

-Alveoli: each bronchiole ends either with an enlargement, or more commonly called with a grapelike cluster of alveoli. -Phospholipid molecules called surfactant, which coats the alveoli, act to keep them open. -Some premature babies have not yet produced enough surfactant to overcome the attractions between the alveolar walls, as a result alveoli collapse after each breathe. This is called respiratory distress syndrome which makes breathing difficult for the premature newborn.

Chapter 12 Know the physical characteristics and function that is unique to each type of blood vessel.

-Arteries: muscular tubes that transport blood AWAY from the heart, delivering it rapidly to the body tissues. Has 3 layers -Arterioles: the smallest arteries, they are barely visible to the unaided eye, walls have the same 3 layers as arteries. Prime controllers of blood pressure and serve as gatekeepers to the capillary networks -Capillaries: microscopic blood vessels that connect arterioles and venules. Main function the exchange of materials between the blood and the body cells. -Venule: After the capillary bed, capillaries merge to form the smallest kind of vein, a venule. Venules then join to form larger veins. -Vein: Blood vessels that return the blood to the heart. Have same 3 layers found in arterial walls, but are thin the lumens are larger.

Chapter 11 What are the ABO and Rh blood types? Know which blood type a person can receive or donate depending on their blood type.

-Blood type O is a universal donor -Blood type AB is a universal recipient/acceptor Blood types are according to the presence or absence of certain molecules, mostly proteins, on the person's red blood cells. -Red blood cells with only the antigen A on their surface area are type A, only B antigen the type is B, blood with both antigens A and B its AB, and Neither A or B antigens present is type O. -Rh factor is important component of blood type. People with Rh are considered positive, without are negative. -Type A = Receives A, O -Type B = Receives B, O -Type AB = Receives A, B, AB, O -Type O = Receives O

Chapter 14 What is asthma?

-Bronchial muscle go into spasms that severely obstruct the flow of air. -A chronic condition characterized by recurring attacks of wheezing and difficulty breathing.

Chapter 11 Which is the most abundant type of leukocyte in the blood? Which releases histamine? Which attacks parasitic worms?

-Neutrophils are the most abundant leukocytes and phagocytes harmful microbes. -Basophils are leukocytes that secrete histamines, a chemical that attracts other white blood cells to the site of infection and causes blood vessels to dilate, increasing blood flow to the affected area, play a role in some allergic reactions. -Eosinophils contain substances that are important in the body's defense against parasitic worms, such as tapeworms and hookworms. They also lessen the severity of allergies.

Chapter 14 What are the functions of the following structures: nose,sinuses, larynx, trachea?

-Nose: filtration and cleansing, conditioning the air, and olfaction. -Sinuses: Lessen the weight of the head, warm and moisten inhaled air. -Larynx: The voice box or Adam's apple. Allows air but not other materials to pass to the lower respiratory system, source of the voice. -Trachea: The windpipe. Conducts air between the outside of the body and the lungs. The main airway, conducts air from the larynx to bronchi.

Chapter 11 What are the major components of blood? (Plasma, formed elements)

-PLASMA: a straw-colored liquid that makes up about 55% of blood. It serves as a medium in which materials are transported by the blood. Carries away cellular wastes, regulates temperature. -FORMED ELEMENTS: platelets, white blood cells, and red blood cells. Platelets or thrombocytes are essential to blood clotting. White blood cells or leukocytes perform certain mundane housekeeping duties such as removing wastes, toxins, damaged or abnormal cells, and serve as warriors in the body's fight against disease. Make up less than 1%of whole blood. Red blood cells or erythrocytes pick up oxygen in the lungs and ferry it to all the cells of the body. most numerous cells in blood, 45% of total blood volume.

Chapter 11 What are the three major classes of formed elements?

-Platelets or thrombocytes are essential to blood clotting. -White blood cells or leukocytes perform certain mundane housekeeping duties such as removing wastes, toxins, damaged or abnormal cells, and serve as warriors in the body's fight against disease. Make up less than 1%of whole blood. -Red blood cells or erythrocytes pick up oxygen in the lungs and ferry it to all the cells of the body. most numerous cells in blood, 45% of total blood volume.

Chapter 11 Where do the formed elements arise from?

-Red bone marrow fills the cavities within many bones and is the birthplace and nursery for the formed elements. -Its sponge-like framework supports fat cells, but it also supports the undifferentiated cells called blood stem cells that divide and give rise to all the formed elements.

Chapter 11 What are the main functions of blood?

-TRANSPORTATION, PROTECTION, and REGULATION -Blood serves as a transportation system. -It carries vital materials to all the cells of the body and carries away the wastes that cells produce. -White blood cells help protect us against disease-causing organisms -Clotting mechanisms help protect us from excessive blood loss when a vessel is damaged. -Buffers in the blood help regulate the acid-base balance of body fluids -Helps regulate body temperature by absorbing heat produced in metabolically active regions and distributing it to cooler regions and to the skin, where the heat is dissipated.

Chapter 12 Which chambers function as a receiving chamber and which are the main pumps?

-The Atria are the receiving chambers for blood returning to the heart. -The ventricles are the main pumps.

Chapter 12 What is pulse, vasoconstriction and vasodilation?

-The alternate expansion and recoil of arteries create a pressure wave called a pulse, that moves along the arteries with each heartbeat. -Vasoconstriction: Reduction in size of diameter of lumen, reduction in blood supply, increase in blood pressure to next vessel -Vasodilation: Larger lumen diameter space, blood supply goes up, decrease blood pressure to next vessel.

Chapter 12 What are the two main circuits of blood flow from the heart?

-The right side of the heart pumps blood through the pulmonary circuit, which transport blood to and from the lungs. Contains blood low in oxygen. -The left side of the heart pumps blood through the systemic circuit, which transports blood to and from body tissues.

Chapter 12 What is the septum and the two types of chambers found in the heart?

-The septum separates the 2 halves of the heart. -Each haf has 2 chambers 1. Atrium: upper chamber, smaller and thin walled (plural form is atria) the receiving chambers 2. Ventricle: lower chamber, larger and more muscular. Ventricles are pumps.

Chapter 14 What is tidal volume, vital capacity, residual volume and total lung capacity? Focus on these and not the others.

-Tidal volume: Amount of air inhaled or exhaled during a normal breath. -Vital capacity: Maximum amount of air that can be inhaled or exhaled in a single forced breathe. -Residual capacity: The amount of air that remains in the lungs after exhaling as much air as possible. -Total lung capacity: The total volume of air contained in the lungs after the deepest possible breath, is calculated by adding the residual volume to the vital capacity. 6000 ml in men, 4500 ml in women.

Chapter 12 What are the three main layers of the heart? What are the physical characteristics that allow them to perform their function?

1. Myocardium: the wall of the heart, mostly cardiac muscle tissue. Its contractions are responsible for the heart's incredible pumping action. 2. Endocardium: Thin lining of cavities of heart, reduces resistance to blood flow through the heart. 3.Pericardium: Thick fibrous sac that holds the heart in the center of the chest (thoracic) cavity and slides over the surface of the heart without hampering its movements, even when they are vigorous.

Chapter 12 What are the three mechanisms employed by the body to move blood from the lower parts of the body toward the heart?

1. Valves in veins prevent backflow of blood. 2. contraction of skeletal muscle squeezes veins 3.Breathing causes pressure changes that move blood toward the heart

Chapter 11 What is anemia?

A condition in which the blood's ability to carry oxygen is reduced, can result from too little hemoglobin, too few red blood cells, or both.

Chapter 11 When whole blood is centrifuged what layers would be observed?

After separation, the uppermost layer in the test tube consists of plasma, 55%. The formed elements are found in two layers below the plasma. Just below the plasma is a very, very thin layer consisting of platelets and white blood cells. The red blood cells are packed at the bottom of the test tube, take up 45%.

Chapter 12 What is the cardiac cycle? Know the difference between systole and diastole.

All the events associated with the flow of blood through the heart chambers during a single heartbeat are collectively called the cardiac cycle. -All chambers relax and blood passes through atria into ventricles. Atria contract, ventricles contract, heart relaxes, and cycle begins again -Systole: contraction -Diastole: relaxation

Chapter 11 What is agglutination?

Blood clumping, or to agglutinate. Can be damaging or even fatal.

Chapter 11 What kind of tissue is blood classified as?

Blood is classified as a CONNECTIVE TISSUE because it contains cellular elements suspended in a matrix, called plasma.

Chapter 12 What is coronary circulation?

Coronary circulation nourishes the heart muscle. -Cells of the heart muscle themselves obtain little nourishment from blood flowing through the heart's chambers. Instead, an extensive network of vessels, the coronary circulation, services the tissues of the heart. -The first 2 arteries that branch off the aorta are the coronary arteries, they give rise to numerous branches, ensuring that the heart receives a rich supply of oxygen and nutrients. -Coronary veins: blood passes through capillary beds, enter coronary veins and flows into right atrium.

Chapter 14 What are the ways carbon dioxide is transported in the blood? What is the main way?

Dissolved in blood plasma, carried by hemoglobin, or as a bicarbonate ion. -70% bicarbonate ion, the main way

Chapter 14 Why are there rings of cartilage in the trachea?

GIves the general appearance of vacuum cleaner hose. They are C-shaped; the open ends of the rings face the side of the trachea next to the esophagus, which allows the esophagus to expand and compress the trachea when a large mass of food is swallowed. its branches prevents these airways from collapsing during each breath when the rapid flow of air into the lungs creates a drop in pressure.

Chapter 12 What is the path that blood takes in regards to blood vessels when it leaves the heart and circulates through the body before returning to the heart? Ex. Heart---->arteries---->arterioles etc.

Heart --> Artery --> Arteriole --> Capillary --> Venule --> Vein --> Heart

Chapter 12 Where does gas exchange take place and by what means. Hint. movement down its concentration gradient.

Heart --> Artery --> Arteriole --> Capillary --> Venule --> Vein --> Heart

Chapter 11 What is hemolytic disease of the newborn? How is it treated?

If the baby's red blood cells, which bear Rh antigens, accidently pass into the mother;s bloodstream, she will produce anti-Rh antibodies. Usually this doesn't have any bad effects associated with the first pregnancy. however, if antibodies are present in the maternal blood from a previous pregnancy with an Rh-positive child or from a transfusion of Rh-positive blood, the anti-Rh antibodies may pass into the blood of the fetus during a subsequent pregnancy. This transfer can occur because anti-Rh antibodies unlike red blood cells, can cross the placenta. These anti-Rh antibodies may destroy the fetus's red blood cells, as a result the child may be stillborn or very anemic at birth. -The Rh-positive cells are killed bu injecting RhoGAM, a serum containing antibodies against the Rh antigens, at the seventh month of pregnancy and shortly after delivery if the baby is Rh positive.

Chapter 14 What mechanisms are involved in breathing? Hint. know what happens to volume and pressure of the thoracic cavity during inhalation and exhalation and why.

Inhalation: -Air moves into the lungs when the size of the thoracic cavity increases, this increase causes the pressure in the lungs to drop below atmospheric pressure. the increase is due to the contraction of both the diaphragm and intercostal muscle. -Also called inspiration. Exhalation: -Also called expiration -Does not require work, occurs when the muscle of the rib cage and the diaphragm relax.

Chapter 12 What two characteristics allow heart cells to beat on their own when outside the heart and also to beat in unison?

It is an inherent property of the cells, but it is partly due to the type of connections between heart muscle cells. The cell membranes of adjacent cardiac muscle cells interweave with one another at specialized junctions called intercalated disks. -The heart muscle does not need outside stimulation to beat, the tendency is intrinsic within the heart muscle itself.

Chapter 14 How does carbon dioxide regulate breathing rate?

Peripheral chemoreceptors in the medulla are near its surface , where they are bathe in cerebrospinal fluid.

Chapter 11 What substances are found dissolved in blood?

Plasma proteins. Make up 7-8% of plasma. -Help balance water flow between the blood and the cells. -Most of the 50 or so types of plasma proteins fall under one of the three general categories. They are antibodies.

Chapter 11 What is the function of platelets and what are they formed from?

Platelets/thrombocytes play an important role in blood clotting. - They are fragments of larger cells called megakaryocytes and are formed in the red bone marrow when megakaryocytes break apart.

Chapter 12 Be able to trace the flow of blood from the right atrium to the aorta. Also know what veins empty into the right atrium.

Right atrium --> tricuspid valve --> right ventricle --> pulmonary semilunar valve --> pulmonary trunk --> right and left lung --> pulmonary veins --> left atrium --> bicuspid valve --> left ventricle --> pulmonary circuit --> aorta The right pulmonary veins empty into the right atrium.

Chapter 12 What is chordae tendineae and what is its function?

The AV valves are connective tissue flaps, called cusps, anchored to the wall of the ventricle by strings of connective tissue called the chordae tendineae-the heartstrings. These strings prevent the AV valves from flapping back into the atria under the pressure developed when the ventricles contract.

Chapter 12 How does the autonomic nervous system affect heart rate?

The autonomic nervous system and certain hormones make the necessary adjustments so that the heart rate suits the body's needs. -During times of stress, the sympathetic nervous system increases the rate and force of heart contractions. -During restful conditions, the parasympathetic nervous system dampens heart activity, in keeping with the body's more modest metabolic needs.

Chapter 14 Where are the respiratory centers located in the brain?

The basic rhythm is controlled by a breathing center in the medulla of the brain.

Chapter 14 Where does gas exchange take place in the lungs?

The pressure changes in the lungs are created by changes in the volume of the thoracic cavity, a relationship explained by the pleural membrane.

Chapter 14 What is the bronchial tree? What kind of muscle can be found there?

The repeated branching of air tubules in the lungs is reminiscent of a branching tree, the resemblance is so close that the system of air tubules is often called the bronchial tree. -The bronchioles have no cartilage, but their walls contain smooth muscle, which is controlled by the autonomic nervous system so that airflow can be adjusted to suit metabolic needs.

Chapter 11 What characteristics help red blood cells efficiently carry oxygen?

The shape is suited for transporting oxygen. It is a small flattened disk, flexible, has no nucleus, is biconcave shape which all maximizes the surface area of the cell, and has hemoglobin, which is the oxygen-binding pigment that provides the red color.

Chapter 12 Know the internal conduction system of the heart. What is the pacemaker of the heart, the AV node and purkinje fibers?

The sinoatrial (SA) node: pacemaker. located in right atrium, causes atria to contract, generates an electrical signal that sets the tempo of the heartbeat. -The tempo of the heartbeat is set by a cluster of specialized cardiac muscle cells, called the sinoatrial (SA) node, located in the right atrium near the junction of the superior vena cava. Since the SA node sends out impulses that initiates each heartbeat, it is often referred to as the pacemaker. -The signal reaches another cluster of specialized muscle cells call the atrioventricular (AV) node, located in the partition between the two atria, and stimulates it. -The atrioventricular bundle that runs along the walls between the ventricles forks into right and left branches then divides into many other specialized cardiac muscle cells, called purkinje fibers, that penetrate the walls of the ventricles.

Chapter 12 What are the types and names of valves found in the heart?

Valves (2 pairs) -Atrioventricular (AV) Valves: separates the atria from the ventricles. AV valve prevents backflow of blood from the ventricle to the atrium. "Lub"=closing of AV valves Tricuspid valve, on the right side of the heart, has 3 flaps. Bicuspid valve (or mitral) valve, on the left side of heart, has 2 flaps -Semilunar Valves: Separate the ventricles from the exit vessels. "Dup"=closing of the semilunar valves

Chapter 12 What is ventricular fibrillation and why is it dangerous?

When the heart's conduction system is faulty, cells may begin to contract independently, these cellular independence can result in rapid, irregular contractions of the ventricles called ventricular fibrillation, which render the ventricles useless as pumps and stop circulation. -It is dangerous because when the brain is no longer receiving blood, death will occur unless an effective heartbeat is restored quickly. Electric shock can be used to restore the heartbeat.