Bio 102: Chapter 42 & 43

A human red blood cell in an artery of the left arm is on its way to deliver oxygen to a cell in the thumb. To travel from the artery to the thumb and then back to the left ventricle, this red blood cell must pass through _____.

2 capillary beds

To adjust blood pressure independently in the capillaries of the gas-exchange surface and in the capillaries of the general body circulation, an organism would need a(n) ___

4 chambered heart

A patient with a heart rate of 70 beats per minute and a stroke volume of 70 mL/beat will have a cardiac output of ______

4,900 mL/minute

Stroke occurs when _____

A blood clot enters the cerebral circulation, blocking an artery and causing the death of brain tissue

You are a cardiologist interested in helping people with long QT syndrome be able to safely engage in exercise. What do you need to manage?

Abnormal electrical activity in the heart

By picking up hydrogen ions, hemoglobin prevents the blood from becoming too ____

Acidic

What is the direct cause of demineralization of the enamel on teeth?

Acids produced by bacteria

A normal event in the process of blood clotting is the ___

Activation of prothrombin to thrombin

Chambers A and B are separated by a membrane permeable to substance X. The concentration of X is 5% in A and 15% in B. The volume of A is three times that of B. What will occur?

Although diffusion is random, the result will be the net movement of X from B to A

Which lung structure is a tiny sac that functions as an interface between air and blood?

Alveoli

Consider the following reaction. If the pH of the blood was decreased, then the ________. CO2 + H2O ↔ H2CO3 ↔ HCO3- + H+

Amount of carbon dioxide would increase

_____ in carbon dioxide in your red blood cells, which causes _____ in pH, causes your breathing to speed up

An increase ... a drop

Cyanide poisons mitochondria by blocking the final step in the electron transport chain. Human red blood cells placed in an isotonic solution containing cyanide are likely to ___

Be unaffected

An oil-water mixture works as an insecticidal spray against mosquitoes and other insects because it ___

Blocks the openings into the tracheal system

The diagnosis of hypertension in adults is based on the ____

Blood pressure being greater than 140 mm Hg systolic and/or greater than 90 mm Hg diastolic

In order for blood to always flow unidirectionally through a closed circulatory system, the ______

Blood vessels farthest from the heart must have valves

The systemic circulation is the higher-pressure circuit to the

Body

Your diaphragm spasms. What bodily function will be most affected?

Breathing

The smallest airway through which inspired air passes before gas exchange occurs in the mammalian lungs is the ____

Bronchiole

High blood pressure in a mammal would most likely result in what?

Bursting of blood vessels in capillary beds

Compared to mammals that are not adapted for diving, diving mammals ______

Can store more oxygen in their muscles

Why does the velocity of blood slow greatly as blood flows from arterioles into capillaries?

Capillary beds have a total cross-sectional area much greater than the total cross-sectional area of the arterioles.

During most daily activities, the human respiration rate is most closely linked to the blood levels of _____

Carbon dioxide

Organisms with a circulating body fluid that is distinct from the fluid that directly surrounds the body's cells are likely to have a _______

Closed circulatory system

In the blood most of the oxygen that will be used in cellular respiration is carried from the lungs to the body tissues ____

Combined with hemoglobin

In order for the diaphragm to form properly, a layer of which tissue develops first?

Connective tissue

During aerobic exercise, the partial pressure of oxygen in muscle cells will ________, thus the rate of diffusion of oxygen into the muscle tissue from the blood will ________

Decrease; increase

Large proteins such as albumin remain in capillaries rather than diffusing out, resulting in the _____

Development of an osmotic pressure difference across capillary walls

Countercurrent exchange in the fish gill helps to maximize _____

Diffusion

Damage to the sinoatrial node in humans would _____

Disrupt the rate and timing of cardiac muscle contractions

What organism has no specialized respiratory structures?

Earthworms

A decrease of blood pH from 7.4 to 7.2 causes hemoglobin to ______

Give up more of its oxygen molecules

Under identical atmospheric conditions, freshwater ______

Has more dissolved oxygen than seawater

Your cousin is quite ill and needs Novalung. What organ will it be connected to?

Heart

You are a transplant doctor. When doing a transplant, you would use ECLS to do the work of what organs?

Heart and lungs

Your aunt is a cardiac surgeon performing surgery on a former marathon runner. Which of the following will she most likely find?

Her patient's heart has larger than average left and right ventricles

Blood and interstitial fluid are considered to be the same body fluid in what group of animals?

Insects

What is the function of a circulatory system?

It brings a transport liquid into close contact with all cells in the body

If a molecule of CO2 released into the blood in your left toe is exhaled from your nose, it does NOT pass through what structure?

Pulmonary Vein

The greatest difference in the concentration of respiratory gases is found in what pair of mammalian blood vessels?

Pulmonary vein and Superior vena cava

From the superior vena cava, blood flows to the ____

Right atrium

The driving force for the diffusion of oxygen from hemoglobin into tissues is

The difference in PO2 levels between the blood (100 mm Hg when oxygenated) and body tissues (40 mm Hg at rest).

The lungs of humans form from

The embryonic foregut

Which of the following respiratory systems is not closely associated with a blood supply?

The tracheal system of an insect

Which event of the cardiac cycle occurs when systolic blood pressure is measured?

The ventricles contract, carrying blood into the aorta, and blood flows into the relaxed atria

Humans infected with some types of parasitic worms develop a condition called elephantiasis, which is characterized by swelling of the limbs. What would most likely cause of elephantiasis?

The worms are blocking the lymph vessels

Countercurrent exchange is evident in the flow of _____

Water across the gills of a fish and the blood within those gills

Compared with the interstitial fluid that bathes active muscle cells, blood reaching these cells in arteries has a

higher P(O2)

flow of air into the lung of a mammal

larnyx → trachea → bronchi → bronchioles → alveoli

Blood returns to the heart via the _____.

pulmonary veins

Sequence of blood flow (beginning at the vena cava) through birds and mammals

vena cava → right atrium → right ventricle → pulmonary artery

When the air in a testing chamber is specially mixed so that its oxygen content is 10% and its overall air pressure is 400 mm Hg, then PO2 is ______

40 mm Hg

A person with a tidal volume of 450 mL (milliliters), a vital capacity of 4000 mL, and a residual volume of 1000 mL would have a potential total lung capacity of ____

5000 mL

Atmospheric pressure at the summit of Mount Everest is about one third the pressure at sea level, which is 760 mm Hg. If oxygen makes up 21% of the atmosphere by volume, the partial pressure of oxygen (PO2) on Mount Everest is approximately _______

53 mm Hg

Most carbon dioxide is carried from the body tissues to the lungs ___

As bicarbonate ions (HCO3 -)

An anthropologist discovers the fossilized heart of an extinct animal. The evidence indicates that the organism's heart was large, was well-formed, and had four chambers, with no connection between the right and left sides. A reasonable conclusion supported by these observations is that the animal was ____

Endothermic and had a high metabolic rate

Your aunt is a biochemical engineer assigned to improve the ECMO machine. This would help with

Gas exchange of oxygen and carbon dioxide

Your cousin finishes an Ironman triathlon. Which of the following is most likely?

His heart will have increased leakiness following the race

What mechanisms are used to regulate blood pressure in the closed circulatory system of vertebrates?

I) Changing the force of heart contraction II) Constricting and relaxing smooth muscle in the walls of arterioles III) Opening or closing precapillary sphincters

How are gases transported in insect bodies?

In tracheal systems

From the pulmonary veins, blood flows to the ____

Left atrium

The pulmonary circulation is the lower-pressure circuit to the

Lung

In an open circulatory system, blood is _____

Not always confined to blood vessels and is under lower pressure than in closed circulatory systems

One feature that amphibians and humans have in common is

Number of circuits for circulation

Capillary beds are the site of

Nutrient and oxygen delivery to tissues

Atrial systole _______

Occurs at the same time as ventricular diastole

What event occurs first during atrial and ventricular diastole?

The atria and ventricles are relaxed, and blood flows into the atria

Why do the circulatory systems of land vertebrates have separate circuits to the lungs and to the rest of the body?

The large decrease in blood pressure as blood moves through the lungs may prevent efficient circulation through the rest of the body

Carbon dioxide levels in the blood and cerebrospinal fluid affect pH. This enables the organism to sense a disturbance in gas levels as _____

The medulla oblongata, which is in contact with cerebrospinal fluid, monitors pH and uses this measure to control breathing

The sun shining on a tidal pool during a hot day heats the water, causing some water to evaporate. Because the water has become warmer and saltier, _______

The oxygen content will decrease

An electrocardiogram (ECG) provides information about _______

The rhythm of heart contractions

Circulatory systems compensate for ___

The slow rate at which diffusion occurs over large distances

An advantage of gas exchange in fresh water, compared with gas exchange in air, is that ____

Water loss through evaporation across the respiratory surface can be minimized

Dentists sometimes give a patient antibiotics after a teeth-cleaning procedure, especially if the patient is older or has heart disease. What is the best explanation for this?

Antibiotics help kill the bacteria that move from the mouth to the bloodstream, and prevent the bacteria from contributing to atherosclerosis

________ is a hormone that is released from the ________ to stimulate the production of red blood cells

Erythropoietin; kidney

Which barrier(s) must O2 and CO2 cross to pass between air and blood inside lungs?

Extracellular fluid, epithelial cells, capillary wall

True or false? The pressure inside the human chest cavity is always positive, so the lungs stay relatively inflated even upon exhalation

False

The only vertebrates in which blood flows directly from respiratory organs to body tissues without first returning to the heart are the _____.

Fishes

To become bound to hemoglobin for transport in mammals, atmospheric molecules of oxygen must cross _______

Five membranesin and out of the cell lining the lung, in and out of the endothelial cell lining an alveolar capillary, and into the red blood cellto bind with hemoglobin

If the osmotic pressure on the venous side of capillary beds is lower than the hydrostatic pressure, then _______

Fluid will tend to accumulate in tissues

In what organism does blood flow from the pulmocutaneous circulation to the heart before circulating through the rest of the body?

Frogs

How has the avian lung adapted to the metabolic demands of flight?

Gas exchange occurs during both inhalation and exhalation

Small swollen areas in the neck, groin, and axillary region are associated with _____

Increased activity in the immune system

The amount of oxygen bound to hemoglobin ___

Increases in the presence of high concentrations of oxygen

From the capillaries of the abdominal organs and hind limbs, blood flows to the ____

Inferior vena cava

What is the function of the left ventricle?

It pumps systemic blood to the lungs via the pulmonary circulation

Blood returning to the mammalian heart in a pulmonary vein drains first into the

Left atrium

Which of the following events would you predict as carbon dioxide is released from your muscles into the surrounding capillary bed?

Oxygen delivery to muscle is increased when more carbon dioxide is produced by the muscle

What is the direct cause of gum disease?

Plaque formed by bacteria

The circulatory systems of bony fishes, rays, and sharks are most similar to the _______

Portal system of mammals

What is the function of valves?

Prevent backflow of blood

Hyperventilation (rapid inhalation and exhalation) can result in respiratory alkalosis (increased blood pH). Why?

Rapid breathing depletes the blood of carbon dioxide, thus the blood pH increases.

What would be the consequence if we were to reverse the direction of water flow over the gills of a fish, moving water inward past the operculum, past the gills, then out the mouth? This reversal of water flow would _______

Reduce efficiency of gas exchange

When you hold your breath, which of the following blood gas changes first leads to the urge to breathe?

Rising CO2

People who produce very little saliva often have more cavities. What is the best explanation for this?

Since saliva normally helps neutralize acid and replace minerals on teeth, a lack of saliva leads to more cavities

What develops the greatest pressure on the blood in the mammalian aorta?

Systole of the left ventricle

What would you expect of a species that has a high resting cardiac output?

The animal likely has a very long distance between its heart and its brain

A rabbit taken from a meadow near sea level and moved to a meadow high on a mountainside would have some trouble breathing. Why?

The partial pressure of oxygen in the air at high elevations is lower than at sea level

Although having evolved independently, the tracheal tubes of mammals and insects are both supported by rigid tissues. The trachea of a mammal is supported by cartilage, and the tracheae of an insect are supported by chitin. What selective pressure most likely led to the convergent evolution of these respiratory structures?

When air is the respiratory medium, there is a greater risk that the tracheal tubes will collapse

While jogging, a person has a stroke volume of 130 ml/beat and a heart rate of 120 beats per minute. If their resting stroke volume was 70 ml/beat and resting heart rate was 60 beats per minute, how did this person's cardiac output change?q

increased from 4,200 ml/minute to 15,600 ml/minute after jogging