week 5 learning curve chapter 37

this blockage will likely increase the resistance to flow in his circulatory system, and as a result, will decrease the rate of blood flow - the blockage will narrow the diameter of the vessel. The decreased diameter increases resistance. If you take the equation Q=P/R when R increases, the value of P/R decreases. Because Q=P/R, then Q flow will decrease as well

a man has just learned that he has a blockage in one of his arteries. Which of the statements is true regarding this blockage?

compared to human hemoglobin, human myoglobin will likely bind to oxygen molecules more quickly when introduced into the oxygen-containing solution - if myoglobin and hemoglobin were both in an oxygen-containing solution, more oxygen molecules would bind to myoglobin because it has a higher affinity for oxygen

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?

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

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?

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

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 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

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?

hemolymph

a school-aged child is dissecting a grasshopper as part of her biology class. as she breaks the exoskeleton, the grasshopper's circulatory fluid leaks out. this fluid would be referred to as:

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 - because atmospheric pressure decreases with altitude, the partial pressure of oxygen is lower at higher altitudes. In order for adequate oxygen delivery to tissues, you would predict the hemoglobin in mountain goats to have a higher affinity for oxygen to offset the lower partial pressures

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?

the affinity of hemoglobin for O2 has decreased

a shift to the right in the hemoglobin dissociation curve means that:

decreasing levels of oxygen in the blood are detected by chemoreceptors in the kidney answers that were true: - as an organism's activity level increases, the level of CO2 in the blood will increase and stimulate faster or stronger breathing - breathing is controlled by both voluntary and involuntary mechanisms - 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

all of these statements are true except:

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

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?

right

during heavy exercise, blood pH will decrease. This will result in a shift to the ________ of the hemoglobin dissociation curve shown

fetal hemoglobin has a higher affinity for O2 than maternal hemoglobin

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

there will be a net diffusion of oxygen from outside the cell to inside the cell

if the partial pressure of oxygen outside of a cell is 100 mmHg and the partial pressure of oxygen inside of a cell is 25 mmHg, which of the statements is correct?

76 mmHg - oxygen makes up 10% of the atmosphere. Multiply 760 mmHg by 0.10 and that gives the partial pressure of oxygen, 76 mmHg

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?

false

t or f: because plants do not have blood, or even hemolymph, you would never expect to find hemoglobin in plants.

true

t or f: diffusion is an effective way to exchange gases over short distances but not over large distances

false

t or f: if a hemoglobin molecule comes into close contact with a respiring cell, the presence of CO2 in the environment will cause hemoglobin to bind to more oxygen molecules (if it is not already bound to four)

false

t or f: in mammals, bulk flow only refers to the movement of oxygen (either into or out of the lungs and within the bloodstream). bulk flow never refers to the movement of carbon dioxide

true

t or f: the binding of one O2 molecule to hemoglobin makes it easier for additional O2 molecules to bind

false

t or f: the most important factor in the control of breathing is the amount of oxygen in the blood

false

t or f: ventilation only refers to the movement of oxygen into and out of air sacs or lungs. As a result, fish and other gilled animals do not experience ventilation

human

the muscles of which of these organisms would likely have the lowest myoglobin concentration?

the weight of a given volume of the gas

the partial pressure of one gas in a mixture is:

air moves into the lungs during inhalation and air moves out of the lungs during exhalation

what is meant by tidal ventilation?

it increases the amount of oxygen that can be carried in the blood

what is the main benefit of having hemoglobin in the blood?

less than 25%

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

the diaphragm relaxes and pushes up

which of the changes occurs during exhalation?

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

which of the choices describes the correct path of air through a bird's respiratory system?

movement of water past a respiratory surface

which of the choices is an example of bulk flow during gas exchange in vertebrates?

ventilation, diffusion across the respiratory surface, circulation, diffusion between blood and cells

which of the choices lists the correct order of steps of gas transport and exchange while breathing?

- the exhalation of CO2 by a human into his or her environment - the transport of O2 in the circulatory system of a frog - 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

which of the choices represents a step in gas transport and/or gas exchange?

concentration gradient

which of the factors affects the rate of diffusion of a substance?

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

which of the statements about bird respiration is true?

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

which of the statements about insect respiration is true?

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

which of the statements is accurate?

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

which of the statements is true regarding CO2 in the mammalian bloodstream?

increasing the surface area of the body

which of these changes would increase the rate of oxygen diffusion from the air into the body cells of a flatworm?

sodium ions

which of these chemicals will not pass through the phospholipid bilayer of a membrane?

- ventilation of the gills with the aid of an operculum - countercurrent exchange - gills with a large surface area - very thin lamellae

which of these choices increase(s) the amount of oxygen that a fish can extract from the surrounding seawater?

salmon (out of the choices: grasshoppers, humans, blue whales, sparrows)

which of these organisms would be able to extract the greatest percentage of oxygen from their respiratory medium?

to trap pathogens and guard against infection

why do cells in the airways of the lungs produce mucus?