Learning Curve ch 37 bio 122

Imagine a planet that has a similar atmospheric pressure to Earth (760 mmHg) but different concentrations of gases in its atmosphere. On this hypothetical planet, oxygen makes up 10% of the atmosphere, carbon dioxide makes up 15%, and nitrogen makes up the remaining 75%. Based on this information, what is the partial pressure of oxygen on this new planet?

76 mmHg

Which of the choices represents a step in gas transport and/or gas exchange? Please choose the correct answer from the following choices, and then select the submit answer button. the diffusion of O2 from the lungs of a horse into its bloodstream the diffusion of CO2 out of mouse cells into a mouse's bloodstream the transport of O2 in the circulatory system of a frog All of these choices are correct. the exhalation of CO2 by a human into his or her environment

All of these choices are correct.

A researcher has sectioned a mouse embryo and notices that certain muscle components (especially myosin) aggregate around the early-stage cartilage of the ribs. Which of the statements is true of these presumptive muscles? These muscles (when they are fully developed) will help to maintain a constant volume in the thoracic cavity. Because they associate with the ribs, these muscles are likely developing intercostal muscles. These muscles likely only serve a supportive role for the ribs and will play no role in breathing. Because they associate with the ribs, these muscles are likely components of the diaphragm.

Because they associate with the ribs, these muscles are likely developing intercostal muscles.

Which of the statements is true regarding CO2 in the mammalian bloodstream? Please choose the correct answer from the following choices, and then select the submit answer button. CO2 is mainly transported through the mammalian bloodstream in the form of bicarbonate ions or carbonic acid. Unlike oxygen, CO2 is transported through the mammalian bloodstream by myoglobin. In the mammalian bloodstream, CO2 is much less soluble than O2. Like oxygen, CO2 is transported through the mammalian bloodstream via hemoglobin; however, CO2 binds to hemoglobin at amine groups rather than heme groups. All CO2 is transported through the mammalian bloodstream as a dissolved gas and is carried directly in the plasma.

CO2 is mainly transported through the mammalian bloodstream in the form of bicarbonate ions or carbonic acid.

Which of the statements about open and closed circulatory systems is correct? Please choose the correct answer from the following choices, and then select the submit answer button. Closed circulatory systems operate under lower pressure than open circulatory systems. Closed circulatory systems use muscular hearts to pump blood through blood vessels, whereas open circulatory systems lack any kind of muscular pump. Closed circulatory systems deliver materials at slower rates than open circulatory systems. Closed circulatory systems can more effectively control the flow of blood to specific body regions than open circulatory systems. Closed circulatory systems have lower resistance to flow than open circulatory systems.

Closed circulatory systems can more effectively control the flow of blood to specific body regions than open circulatory systems.

A researcher has introduced molecules of human myoglobin and hemoglobin into a solution containing oxygen. Which of the statements is true of human hemoglobin and myoglobin?

Compared to human hemoglobin, human myoglobin will likely bind to oxygen molecules more quickly when introduced into the oxygen-containing solution.

All of the statements are true except: -Breathing is controlled by both voluntary and involuntary mechanisms. -Decreasing levels of oxygen in the blood are detected by chemoreceptors in the kidney. -Chemoreceptors involved in the homeostatic control of breathing are located in the brainstem and the carotid and aortic bodies. -Stronger or more frequent contraction of respiratory muscles helps to remove excess CO2 from the blood. -As an organism's activity level increases, the level of CO2 in the blood will increase and stimulate faster or stronger breathing.

Decreasing levels of oxygen in the blood are detected by chemoreceptors in the kidney.

How is a fetus able to extract O2 from its mother's blood?

Fetal hemoglobin has a higher affinity for O2 than maternal hemoglobin.

A scientist is evaluating the hemoglobin in mountain goats compared to the hemoglobin in normal barnyard goats. How will the hemoglobin in these two goat species compare? Given that mountain goats tend to live at higher altitudes, hemoglobin in these goats will have more heme groups than the hemoglobin of barnyard goats. Given that mountain goats tend to live at higher altitudes, these goats will have hemoglobin with a greater oxygen-binding affinity compared to the hemoglobin of barnyard goats. As these are both goat species, mountain goats and barnyard goats will have the same type of hemoglobin (with the same binding affinity for oxygen). Given that barnyard goats tend to live at lower altitudes, hemoglobin in these goats will have more heme groups than the hemoglobin of mountain goats. Given that barnyard goats tend to live at lower altitudes, these goats will have hemoglobin with a greater oxygen-binding affinity compared to the hemoglobin of mountain goats.

Given that mountain goats tend to live at higher altitudes, these goats will have hemoglobin with a greater oxygen-binding affinity compared to the hemoglobin of barnyard goats.

What is the main benefit of having hemoglobin in the blood? Please choose the correct answer from the following choices, and then select the submit answer button.

It increases the amount of oxygen that can be carried in the blood.

Which of the statements about myoglobin is true? Please choose the correct answer from the following choices, and then select the submit answer button. When fully saturated, myoglobin carries more O2 molecules than hemoglobin. Myoglobin is found within vertebrate muscle cells. Myoglobin binds O2 with the same affinity as hemoglobin. Myoglobin has a lower affinity for O2 than hemoglobin.

Myoglobin is found within vertebrate muscle cells.

Which of the statements about veins is true? Please choose the correct answer from the following choices, and then select the submit answer button. The blood pressure within the veins is much lower than the blood pressure within the arteries. Veins located in the head have one-way valves that help prevent blood from pooling due to gravity. Only 20% of the total blood volume resides in the venous circulation at any given time. Veins have thicker walls than arteries.

The blood pressure within the veins is much lower than the blood pressure within the arteries.

If heart rate decreases 30% followed by stroke volume decreasing 10%, then what effect do these decreases have on the total cardiac output

The cardiac output decreases by 37%.

Which of the changes occurs during exhalation? Please choose the correct answer from the following choices, and then select the submit answer button. Intercostal muscles elevate the ribs. The volume of the thoracic cavity increases. The diaphragm relaxes and pushes up. Negative pressure in the lungs increases. None of the answer options is correct.

The diaphragm relaxes and pushes up.

A researcher is studying a strain of mice that only incorporates 50% of the necessary iron into their hemoglobin molecules. Which of the statements is likely true regarding these mutant mice?

The hemoglobin in these mutant mice will be able to bind half the number of oxygen molecules compared to the hemoglobin of normal or wild-type mice.

Which of the statements about insect respiration is true? Please choose the correct answer from the following choices, and then select the submit answer button. Air enters the bodies of insects through the mouth. Air sacs in many insects hold air for use during the night. The insect respiratory system is composed of a series of branching tubes called tracheae. After diffusing through the walls of the tracheoles, oxygen is delivered to the body tissues by the circulatory system.

The insect respiratory system is composed of a series of branching tubes called tracheae.

A researcher is culturing cells that require oxygen to live in an incubator where the gas levels are carefully regulated. If the researcher observes that the pO2 in the incubator is 200 mmHg, what can the researcher deduce about the pO2 of her cells?

The pO2 of her cells is less than or equal to 200 mmHg.

At any given point along the length of the gill lamella, how does the pO2 of the blood flowing through the blood vessels in the lamella compare to the pO2 of the water flowing over the gill lamella? Please choose the correct answer from the following choices, and then select the submit answer button. The pO2 in the blood is equal to the pO2 of the water. The pO2 of the blood is higher than the pO2 of the water. The pO2 of the blood never exceeds 50% of the pO2 of the water. The pO2 of the blood is lower than the pO2 of the water. The pO2 of the blood is variable and cannot be compared to the pO2 of the water.

The pO2 of the blood is lower than the pO2 of the water.

Which of the statements is true? The repolarization of the pacemaker cells following an action potential allows the heart to relax between contractions. Pacemaker cells repolarize by opening voltage-gated sodium channels. The rapid depolarization phase of the action potential in pacemaker cells results from the influx of sodium through voltage-gated sodium channels. The resting membrane potential of cardiac pacemaker cells gradually becomes more negative on its own.

The repolarization of the pacemaker cells following an action potential allows the heart to relax between contractions.

Which of the statements is accurate? Please choose the correct answer from the following choices, and then select the submit answer button. Larger, more complex animals and smaller, simpler animals rely on bulk flow and diffusion to deliver oxygen to their cells. Circulation requires a pump to generate pressure to drive flow, whereas ventilation does not. The same amount of oxygen enters the blood through diffusion as is transported by circulation. Only Oxygen, not carbon dioxide, moves across the respiratory surface by diffusion. Ventilation increases the concentration of oxygen in the air on the inside of the respiratory surface.

The same amount of oxygen enters the blood through diffusion as is transported by circulation.

Which of the statements about bird respiration is true? Please choose the correct answer from the following choices, and then select the submit answer button. Air flowing through the air channels in the lungs moves in a tidal fashion. Oxygen is exchanged between the air, the bloodstream in the lungs, and the air sacs. It takes four ventilation cycles for a single breath of air to move through a bird's respiratory system. The unidirectional flow of air through a bird's lungs maintains a larger concentration gradient for diffusion than can be obtained through tidal breathing. Bird lungs receive fresh air only during inhalation.

The unidirectional flow of air through a bird's lungs maintains a larger concentration gradient for diffusion than can be obtained through tidal breathing.

A man has just learned that he has a blockage in one of his arteries. Which of the statements is true regarding this blockage? This blockage will likely decrease the resistance to flow in his circulatory system, and as a result, will decrease the rate of blood flow. This blockage will likely increase the resistance to flow in his circulatory system, and as a result, will decrease the rate of blood flow. This blockage will likely increase the resistance to flow in his circulatory system, and as a result, will increase the rate of blood flow. This blockage will likely decrease the resistance to flow in his circulatory system, and as a result, will increase the rate of blood flow.

This blockage will likely increase the resistance to flow in his circulatory system, and as a result, will decrease the rate of blood flow.

Which of the factors affects the rate of diffusion of a substance? Please choose the correct answer from the following choices, and then select the submit answer button. viscosity direct supply of metabolic energy (ATP) concentration gradient presence of other solutes

concentration gradient

Cardiac output equals:

heart rate times stroke volume.

Which of these changes would increase the rate of oxygen diffusion from the air into the body cells of a flatworm? Please choose the correct answer from the following choices, and then select the submit answer button. increasing the surface area of the body increasing the partial pressure of oxygen inside the cells increasing the thickness of the body wall increasing the surface area of the body and the partial pressure of oxygen inside the cells All of these choices are correct.

increasing the surface area of the body

Which of the choices describes the correct path of air through the human respiratory system?

larynx, trachea, bronchi, bronchioles, alveoli

What percentage of oxygen in the air is typically extracted by the mammalian lung when an animal is resting?

less than 25%

At the venous end of a capillary, the blood pressure is _____ the osmotic pressure and fluid _____ the blood vessel.

lower than; moves into

Which of the choices is an example of bulk flow during gas exchange in vertebrates? Please choose the correct answer from the following choices, and then select the submit answer button. movement of hemolymph throughout the body movement of oxygen from the lungs into the bloodstream movement of water past a respiratory surface movement of carbon dioxide from body cells into the bloodstream All of these choices are correct.

movement of water past a respiratory surface

The pulmonary veins carry:

oxygenated blood from the lungs to the left atrium.

In which of the heart chambers would deoxygenated blood be found?

right atrium and right ventricle

Which of these chemicals will not pass through the phospholipid bilayer of a membrane? Please choose the correct answer from the following choices, and then select the submit answer button. carbon dioxide sodium ions molecular oxygen

sodium ions

In the disease elephantiasis, lymph vessels become blocked because of infection with parasitic worms. Which of the processes would be impacted by this disease?

the return of excess interstitial fluid to the bloodstream

Dilated pupils, inhibited digestive activity, increased respiratory rate, and release of glucose from the liver are all signs of activity of:

the sympathetic division of the autonomic system.

Why do cells in the airways of the lungs produce mucus? Please choose the correct answer from the following choices, and then select the submit answer button. to move oxygen into solution so that it can diffuse into the bloodstream to prevent the diffusion of blood into the alveoli to trap pathogens and guard against infection to decrease the surface tension (of liquids) in the lung

to trap pathogens and guard against infection

Which of the choices describes the correct path of air through a BIRD'S respiratory system?

trachea, posterior air sacs, lungs, anterior air sacs, trachea

The binding of one O2 molecule to hemoglobin makes it easier for additional O2 molecules to bind. Please choose the correct answer from the following choices, and then select the submit answer button. true false

true