Chapter 23

Lungs as respiratory surface

- Lungs: An internal sac, lined with moist epithelium, where gases are exchanged between inhaled air and the blood. - snails, some spiders, some amphibians, birds, reptiles, mammals

Tracheal system (tracheae as respiratory surface) In insects, an extensive network of branching internal tubes called tracheae, used in respiration.

- Trachea begin near body's surface and branch down to narrower tubes that extend to most cells - Gas exchange occurs via diffusion across the moist epithelium that lines the tips of the tubes - Almost every body cell is near respiratory surface so no needed assistance from circulatory system

2. Describe the three main components of circulatory systems.

3 main components: central pump, a vascular system (set of tubes), and a circulating fluid

Negative pressure breathing

A breathing system in which lower air pressure in the lungs causes air to enter the lungs.

closed circulatory system

A circulatory system in which blood is confined to vessels and is kept separate from the interstitial fluid.

open circulatory system

A circulatory system in which the circulating fluid is pumped through open-ended vessels and out among the body cells. In an animal with an open circulatory system, the circulating fluid and interstitial fluid are the same.

Stem cell

A relatively unspecialized cell that can give rise to one or more types of specialized cells.

cardiovascular disease: definition, frequency, how does it work

A set of diseases of the heart and blood vessels,that results when the cardiovascular system cannot perform its normal functions. Accounts for 40% of all US deaths, killing more than 1 million people per year. Heart muscles require O2 rich blood in tissue. When blood exits the heart, the coronary arteries branch off the aorta to feed heart muscle. If the coronary arteries are blocked than heart muscle can die from lack of O2. This event and subsequent failure of the heart to function properly is called a heart attack.

Trace the path of a breath of air as it travels to and from the deepest portions of the lungs.

Air enters nasal cavity or mouth, then travels to pharynx, larynx (voice box), trachea (windpipe), bronchi, bronchioles, and bronchioles end in grapelike cluster of air sacs called alveoli where gas exchange occurs. Goes in opposite direction after gas exchange. During exhalation outgoing layer moves over pair of vocal cords within the larynx. You produce vocal sounds by flexing muscles in voice box as air rushes by.

what are 4 types of respiratory surfaces and the types of animals that use them

Skin- Earthworm Gills- Fish Tracheal system- Insects Lungs- Humans

Explain how stem cells can be used to fight leukemia.

Stem cells, which are produced in red bone marrow, can continually reproduce and create both WBC and RBC so they can be used to create healthy WBC (that could help fight the spread of cancer) and RBC (may be lack of due to overcrowding in bone marrow)

Explain how the cardiovascular system contributes to homeostasis.

The cardiovascular system contributes to homeostasis by keeping relatively constant internal conditions. It helps control chemical balance of fluid that surrounds cells by exchanging nutrients and wastes with the interstitial fluid. Cardiovascular system also helps control composition of blood by moving it through organs that regulate the bloods content such as the liver, lungs, kidneys. Also helps regulate body temperature, hormone distribution, and helps provide defense against foreign invaders.

Explain how the circulatory and respiratory systems cooperate to facilitate gas exchange.

The circulatory system transports gases and other substances to and from body cells. Within all cells, the process of cellular respiration requires O2 and glucose to produce water, CO2, and ATP. All working cells need a steady supply of O2 from the environment and need to constantly dispose of CO2. The respiratory system consist of several organs that facilitate exchange of )o2 and CO2 between cells and the environment.

Osmoregulation

The control of the gain or loss of water and dissolved solutes in an organism. Osmoregulation is based largely on regulating solutes because water follows the movement of solutes by osmosis.

Explain how cigarette smoking affects public health

The public can be affected by tobacco smoke because secondhand cigarette smoke is a substantial health hazard, especially to children.

Describe the path of blood as it makes one full circuit through the body, including the heart.

two large veins empty oxygen-poor blood into the right atrium b. the blood is received in the right ventricle, which pumps the oxygen-poor blood to the lungs via c. two pulmonary arteries d. as the blood flows through the lung capillaries, (gas exchange) CO2 diffuses out of blood abd O2 diffuses into the blood. e. The newly O2 rich blood flows through pulmonary veins to f. The left atrium of the heart, this completes the pulmonary circuit g. The left ventricle receives blood pumped from left atrium h. The O2 rich blood leaves the left ventricles through the aorta (largest blood vessel in body) that branch into coronary arteries that supply i. the head and arms and abdominal region and legs. Within each organ arteries branch into arterioles and capillaries that penetrate tissue (gas exchange across thin wall of capillary). The o2 poor blood goes from capillaries to venules to veins j. O2 poor blood from head and upper body is channeled in superior vena cava (a large vein) k. O2 poor blood from lower body flows through inferior vena cava. Both superior and inferior vena cava complete the systemic circuit by returning blood to heart

Describe the components of blood and their functions.

Blood Transports, Regulates, and protects. Plasma o 90% water o 10% salts, proteins and other molecules o Cells o Red blood cells (erythrocytes) • Carb-containing molecules on the surface of red blood cells determine blood type • RBC are disk shaped and have indetations in the middle so there is more surface area • RBC contain hemoglobin (which contains iron) that can bond to oxygen and deliver oxugen to cells • Lack nuclei and other organelles so more hemoglobin allowed o White blood Cells (leukocytes) • Fight infection and are larger than RBC • Contain nuclei and organelles o Platelets • Bits of cytoplasm-enclosed membrane that aid clotting • Release molecules that convert fibrogen (protein in plasma) to thread-like protein called fibrin • Fibrin molecules create dense network to form a patch (a scab)

Describe the three phases of gas exchange in humans.

1. Breathing: The ventilation of the lungs by alternate inhalation and exhalation, supplying a lung or gill with O2-rich air or water and expelling CO2-rich air or water. When lungs breathe, large and moist internal structure exposed to air. O2 diffuses across lining of lung cells and into surrounding blood vessels. 2. Transport of gases by the circulatory system: o2 is transferred to blood through capillaries and to rest of body by circulatory system 3. Exchange of gases with body cells: o2 diffuses from RBC into body cells which release co2 into blood. O2 used for cellular respiration. Co2 is waste product and through circulatory system it returns to lungs and is exhaled.

Hypertension: definition, how many people it effects, and why is it called "silent killer"

Abnormally high blood pressure consisting of a persistent systolic blood pressure higher than 140 and/or diastolic blood pressure higher than 90. This condition can lead to a variety of serious cardiovascular disorders. o Affects ¼ of adult population of US o "silent killer" = often doesn't express outward symptoms but increases risk of heart disease, heart attack, or stroke

1. Explain why most animals require a circulatory system.

All organisms must exchange materials and energy with its environment. Simple animals such as hydras only use diffusion to exchange materials. Most animals, however, are too large and complex for exchange to take place by diffusion alone. In particular, oxygen needs to be brought into the body and carbon dioxide needs to be released.

Osmoregulator

An organism whose body fluids have a solute concentration different from that of its environment and that must use energy in controlling water loss or gain.

Osmoconformers

An organism whose body fluids have a solute concentration equal to that of its surroundings. Osmoconformers do not have a net gain or loss of water by osmosis.

Relate the anatomy of the human urinary system to its functions.

Anatomy of urinary system a. Blood enters kidney by the renal artery i. Renal artery branches into millions of thin blood vessels ii. Supplies blood to nephron (tubule and its associated blood vessels, each kidney has a million )by capillaries b. Filtered blood leaves via renal vein 23. Nephrons carry out functions of urinary system 24. Blood pressure force water and solutes from blood through a filter at the start of the nephron tubule, making filtrate a. Filtrate passes through tubule, where water and important nutrients are reabsorbed into the bloodstream and wastes are secreted into filtrate b. Filtrate becomes more concentrated, resulting in urine c. Urine leaves nephron and collects in the kidney via ureter d. Stored in urinary bladder and is expelled periodically through the urethra 25. Functions performed by each nephron (summary of what was just said) a. Filtration i. Water and other small molecules are forced from the blood through capillary wall into a kidney tubule, forming filtrate b. Reabsorption i. Water and important solutes are reclaimed from filtrate and put back in blood c. Secretion i. Ions and drugs are transported into filtrate, gets more concentrated until it is urine d. Excretion i. Urine passes from kidneys to outside 26. When solute concentration of body fluids raises too high, (not enough water is present), brain increases levels of a hormone called ADH in the blood which signals the nephrons to reabsorb more water from the filtrate, increasing the body's water content 27. When body fluids become too dilute, ADH levels drop, kidneys reabsorb less water, and urine is clear 28. When kidneys fail, body is unable to rid itself of wastes a. A person can function on one kidney but not zero b. Dialysis, filtration of the blood by a machine that mimics the action of a nephron can be used but it takes 4-6 hours 3 days a week and is expensive 29. There are not enough kidney donors for people who need kidneys

Leukemia

Cancer of the white blood cells (leukocytes), characterized by excessive production of these cells, resulting in an abnormally high number in the blood. The large number of defective WBC overcrowd bone marrow cells that produce RBC and platelets, casuing severe anemia and impaired clotting.

Gills as respiratory surface

Gills: An extension of the body surface of an aquatic animal, specialized for gas exchange and/or suspension feeding. Lobsters, fishes Gills have greater respiratory surface area (because many branch points) than the rest of body surface As water passes over gills, gases diffuse between water and blood, and then blood carrier o2 to rest of body

a. Compare the structures of open and closed circulatory systems; central pump:

In Closed circulatory system: heart is the chambered muscular organ in vertebrates that pumps blood received from veins to arteries, thereby maintaining the flow of blood through the entire circulatory system. Atrium: heart chamber that collects blood from body or lungs via veins. Ventricle: a heart chamber that pumps blood to the body or lungs via arteries. In Open circulatory system: tubular heart that runs length of body

Explain how blood is returned to the heart.

In a capillary, the oxygen rich blood and nutrients flow from an artery to an arteriole and then the capillaries. The oxygen and nutrients diffuse out of the capillary and into tissue cells. Meanwhile, co2 and wastes diffuse out of tissue cells and into capillaries, into venules and veins. Skeletal muscle contracts and pushes the oxygen poor blood up veins (superior and inferior vena cava) and back to the right atrium.

how a shortage of iron interferes with oxygen transport

Iron is important in structure of hemoglobin, so an iron shortage causes less hemoglobin to be produced. Irondefiency is the most common cause of anemia.

How smoking interferes with oxygen transport

It exposes your respiratory tissues to potentially damaging chemicals. Tobacco smoke contains more than 4,000 different chemicals (some are toxic) attached to its carbon particles. The epithelial tissue lining our respiratory system is very delicates, its best protection is mucus covering the cells and the beating hairlike cilia that sweep dirt and microorganisms off their surfaces. Tobacco smoke destroys the cells that line the bronchi and trachea, destroying their cilia so more toxins will not be swept out so they can build up.

20. Describe the functions of the kidneys. Explain how the structure of the human kidney contributes to the process of osmoregulation.

Kidneys a. Contains 100 miles of thin tubes called tubules and capillaries b. When blood circulates through the body, some of it is filtered and plasma enters kidney tubules where it is then called filtrate c. Filtrate has substances that the body needs and substances that they need to dispose d. Kidneys refine filtrate, getting rid of urea (nitrogen-containing compound produced from proteins and nucleic acids) but don't get rid of all nutrients and cause dehydration

Describe the process of breathing and explain how it is controlled.

Negative pressure breathing: A breathing system in which lower air pressure in the lungs causes air to enter the lungs. o Inhalation (air pressure is higher in atmosphere than in lungs): diaphragm contracts (moves down) and rib cage expands as rib muscles contract; this allows space for incoming air molecules o Exhalation (air pressure is lower in atmosphere than in lungs): diaphragm relaxes (moves up) and rib cage gets smaller as rib muscles relaxes; this decrease space in lungs for air molecules so diffusion out of body o Nerves from breathing control centers in brainstem send signals and maintain respiratory rate 1. levels of co2 in blood affect breathing rate. Co2 levels in the blood rise as a result of exercise (output cellular respiration) 2. breathing control centers in the brain monitor the rising co2 levels in the blood 3. nerve signals trigger contraction of muscles (so more co2 is eliminated in exhaled air and more o2 provided to muscles) to increase breathing rate and depth

3. Know the structures and functions of the human pulmonary and systemic circuits.

Pulmonary circuit: conveys blood between heart and lungs, the path of blood only includes the heart and lungs Systemic circuit: conveys blood between heart and rest of body; the blood supplies nutrients and oxygen to body tissues and organs and picks up CO2 and other wastes from them

Pulse

Pulse: The rhythmic stretching of the arteries caused by the pressure of blood forced through the arteries by contractions of the ventricles during systole.

Inhalation (air pressure is higher in atmosphere than in lungs)

diaphragm contracts (moves down) and rib cage expands as rib muscles contract; this allows space for incoming air molecules

Exhalation (air pressure is lower in atmosphere than in lungs)

diaphragm relaxes (moves up) and rib cage gets smaller as rib muscles relaxes; this decrease space in lungs for air molecules so diffusion out of body

6. Know the structure of blood vessels and their functions.

i. Arteries: large vessels that carry blood away from the heart to other parts/tissues of the body 1. Epithelium layer 2. Middle smooth muscle layer which relaxes and contracts in response to signals from brain; smooth muscle can narrow or widen vessels , thereby regulating blood flow; thicker 3. Thicker connective tissue because more blood pressure. Connective tissue is elastic and allows vessels to stretch and recoil 4. Arterioles: A small vessel that conveys blood between an artery and a capillary bed. ii. Capillaries: A microscopic blood vessel that conveys blood between an artery and a vein or between an arteriole and a venule; enables the exchange of nutrients and dissolved gases between the blood and interstitial fluid. 1. Epithelium 2. Very thin walls to allow for gas exchange iii. Veins: In animals, a vessel that returns blood to the heart. 1. Epithelium 2. Thinner smooth muscle 3. Thinner connective tissue because less blood pressure 4. Valves that prevent backflow

blood pressure : definition, and how blood pressure is expressed, and typical blood pressure

o Blood pressure: The force that blood exerts against the walls of the blood vessels (particularly arteries, so they squeeze artery and see how much the mercury raises to measure b.p) o Expressed with blood pressure during systole as numerator and blood pressure in diastole as denominator o 120/80 is typical

a. Explain how the presence of carbon monoxide interferes with oxygen transport.

o Carbon monoxide can bond to hemoglobin even more tightly than it can bind to o2. So a carbon monoxide bond can interfere the delivery of o2 to body cells and therefore will interfere will cellular respiration and cause rapid death.

5. Explain how heart rate is regulated and detected by an EKG (ECG).

o Heart rate is regulated by pacemaker also called the SA (sinoatrial) node. SA node: a region of cardiac muscle that maintains the heart's pumping rhythm (heartbeat) by setting the rate at which the heart contracts by sending electrical impulses that make the atria contract. o electrocardiogram (ECG or EKG) : A record of the electrical impulses that travel through heart muscle during the cardiac cycle. o These electrical impulses can be detected by electrodes placed on the skin

Describe the functions of hemoglobin.

o Hemoglobin carries oxygen within RBC. Each hemoglobin molecule has 4 polypeptide chains each with attached chemical group called a heme o A heme has an iron center atom that can hold one o2 molecules o So hemoglobin holds up to 4 o2 molecules

Skin as respiratory surface

o Skin: earthworm o Moist skin that allows for gas exchange across its whole body surface o Must live in wet environments to keep skin moist o The capillaries and plasma membrane of cells are very close to outside environment so O2 and CO2 can easily diffuse across the skin.