Cardiopulmonary Quiz 1 Practice

Isometric contraction is the best term to describe when the length of muscle fibers remains constant and the velocity of shortening is 0. In isometric contractions, the muscle generates force without changing length, such as when holding a static position or pushing against an immovable object. This type of contraction is important for maintaining posture and stability. Eccentric contraction refers to the lengthening of muscle fibers, while isotonic contraction involves muscle shortening with a constant tension.

Boyle's Law states that the pressure and volume of a gas are inversely proportional at a constant temperature. In the context of the lungs, when we inhale, the volume of the lungs increases, causing a decrease in pressure, which allows air to flow into the lungs. Similarly, when we exhale, the volume of the lungs decreases, causing an increase in pressure, which forces air out of the lungs. Therefore, Boyle's Law is applicable in the lungs as they act as a closed container during the process of breathing.

P=QR Pressure=Flow*Resistance

All of the factors mentioned in the options (frequency of stimulation, thickness of each muscle fiber, and the initial length of the muscle fiber) influence the strength of muscle contraction. The frequency of stimulation determines the rate at which muscle fibers contract, and a higher frequency leads to stronger contractions. The thickness of each muscle fiber affects the number of myofibrils present, which in turn affects the force generated during contraction. The initial length of the muscle fiber also plays a role as it affects the overlap of actin and myosin filaments, which impacts the force generated. Therefore, all of these factors contribute to the strength of muscle contraction.

Smooth muscle is the correct answer because it is the only type of muscle that is nonstriated and innervated by the autonomic nervous system. Skeletal muscle is striated and is innervated by the somatic nervous system, while cardiac muscle is striated and is innervated by both the autonomic and somatic nervous systems. Smooth muscle is found in the walls of organs, blood vessels, and other structures, and its contraction is involuntary and controlled by the autonomic nervous system.

High blood pressure in a patient with congestive heart failure can lead to increased pressure in the veins. This can cause the jugular veins in the neck to become engorged or swollen. This can be observed visually as the veins in the neck may appear more prominent or bulging. This is due to the impaired ability of the heart to pump blood effectively, leading to increased pressure in the veins and fluid accumulation in the body.

As the radius goes down resistance goes up

The statement is true because conduits for air, lymph, and blood primarily have unidirectional flow, except for air which is bidirectional. This means that air, lymph, and blood flow in one direction through their respective conduits, ensuring efficient transportation and distribution throughout the body. However, air flow is bidirectional as it can be inhaled and exhaled through the same pathway, allowing for the exchange of gases in the respiratory system.

When the chest wall expands, it creates more space in the chest cavity, allowing the lungs to expand. As the lungs expand, the volume of the chest cavity increases. This increase in volume leads to a decrease in pressure within the chest cavity. Therefore, as the chest wall expands, volume increases and pressure decreases.

A twitch is the correct term to describe when a muscle is stimulated with a single electrical shock, resulting in a quick contraction followed by immediate relaxation. This term is used to describe the brief and isolated response of a muscle to a single stimulus. It is different from summation, which refers to the increased force of contraction when multiple stimuli are applied rapidly, and from incomplete and complete tetanus, which involve sustained contractions of varying degrees.

Complete tetanus is the best term to describe a smooth sustained contraction with no visible relaxation between twitches. In complete tetanus, the muscle fibers are stimulated at a high frequency, causing them to contract and remain contracted without any periods of relaxation. This results in a continuous and sustained contraction of the muscle, with no visible twitches or breaks in the contraction.

Cardiac muscle is the correct answer because it is striated, meaning it has a striped appearance, and it is innervated by the autonomic nervous system. Unlike skeletal muscle, which is under voluntary control, cardiac muscle is involuntary and is responsible for the contraction of the heart. Smooth muscle, on the other hand, is also involuntary but is not striated and is found in organs such as the intestines and blood vessels.

Skeletal muscle is the correct answer because it is the only muscle type that is both striated and innervated by the somatic nervous system. Striated muscles have a striped appearance due to the arrangement of contractile proteins, and skeletal muscles fall under this category. Additionally, the somatic nervous system controls voluntary movements, which includes the contraction and relaxation of skeletal muscles. Cardiac muscle, found in the heart, is also striated but is innervated by the autonomic nervous system. Smooth muscle, found in the walls of organs, is not striated and is innervated by the autonomic nervous system.

Skeletal muscle is innervated by the somatic nervous system in which acetylcholine is excitatory.

Isotonic contraction is the correct term to describe when the force of contraction remains constant throughout the shortening process. In isotonic contraction, the muscle shortens while maintaining a constant tension or force. This type of contraction is commonly seen in activities such as lifting weights or performing bicep curls, where the muscle shortens as it contracts against a constant load.

The answer is both because smooth muscle is innervated by the autonomic nervous system which uses Norepinephrine in excitatory actions and Acetylcholine in inhibitory actions

When resistors are connected in parallel, the total resistance across the total path is always less than the resistance through any single path. This is because in a parallel circuit, the current has multiple paths to flow through, and each path offers less resistance compared to a single path. As a result, the total resistance decreases, allowing more current to flow through the circuit.

Negative feedback is a type of control system that is considered the workhorse for controlling homeostasis. It helps maintain stability by reversing any deviations from the desired set point. In negative feedback, the output of the system is used to counteract the input, thereby reducing the deviation. This control system contains an odd number of inverse relationships, meaning that the output of the system opposes the input. This ensures that the system self-regulates and maintains equilibrium.

Both A and C are correct. The alveolar PO2 is greater than the PO2 found in the lung capillary because oxygen diffuses from the alveoli into the capillary, resulting in a higher partial pressure of oxygen in the alveoli. Similarly, the alveolar PCO2 is less than or equal to the PCO2 found in the lung capillary because carbon dioxide diffuses from the capillary into the alveoli, resulting in a lower partial pressure of carbon dioxide in the alveoli.

The left bronchial tube has a sharper angel to compensate for the position of the heart, thus the more direct rout of infection would be to travel into the right lung

The blood pressure actually decreases as it flows from the heart out to the peripheral circulation. This is because the resistance to blood flow increases as the blood vessels become smaller and more numerous in the peripheral circulation. As a result, the pressure exerted by the blood on the walls of the blood vessels decreases. Therefore, the statement "The blood pressure increases as it flows from the heart out to the peripheral circulation" is false.

Summation is the term that best describes when a second electrical shock is administered before complete relaxation of the muscle. Summation occurs when the muscle is stimulated again before it has fully relaxed from the previous stimulation, causing a stronger contraction. This can result in a sustained contraction and increased muscle tension. In contrast, a twitch refers to a brief and single contraction of the muscle, while incomplete tetanus is a sustained contraction with partial relaxation, and complete tetanus is a sustained contraction without any relaxation.

The percent blood volume is highest in the venous system because veins have a larger capacity to hold blood compared to arteries. Veins are thin-walled and have valves that prevent backflow of blood, allowing them to accommodate a larger volume of blood. Additionally, veins act as a reservoir for blood, storing it and releasing it when needed, such as during exercise or in cases of blood loss. Arteries, on the other hand, have thicker walls and are responsible for carrying oxygenated blood away from the heart to the rest of the body.

Mercury is 13.6 times more dense than blood or water. This means that for every unit of volume, mercury weighs 13.6 times more than the same volume of blood or water. In other words, mercury is much denser and heavier compared to blood or water.

Capillaries have the highest cross-sectional area and surface area compared to arteries, veins, and the aorta. This is because capillaries are the smallest blood vessels in the body and are responsible for the exchange of oxygen, nutrients, and waste products between the blood and surrounding tissues. The large number and small size of capillaries allow for a greater total cross-sectional area, which facilitates efficient exchange of substances. Additionally, the extensive branching and network of capillaries increase the overall surface area available for exchange. Therefore, capillaries have the highest cross-sectional area and surface area among the given options.

Both a and c are correct because in the graph, as the volume increases (as shown in column A), the pressure decreases (as shown in column B). This relationship between volume and pressure is consistent with Boyle's Law, which states that as the volume of a gas increases, the pressure of the gas decreases, assuming constant temperature. Therefore, both statements a and c accurately describe the relationship between volume and pressure in the given graph.

i.e
lbs per sq in (psi)
dynes/sq cm
P = Energy/Volume or Work/Volume

The statement suggests that the nesting of cycles in complex systems does not decrease the stability of the regulated variable. In complex systems, the nesting of cycles can actually enhance stability by providing feedback loops that help regulate and maintain the variable within desired limits. These feedback loops can help counteract disturbances and maintain equilibrium, ultimately contributing to stability rather than decreasing it.

The correct answer is "All of the above." This means that the pressure at the mouth (Pm) can be 0 mm Hg relative to atmospheric pressure, 760 mm Hg, or the same as resting alveolar pressure. In other words, the pressure at the mouth can be any of these options, as they are all equivalent.

Incomplete tetanus is the term that best describes an increasing frequency of electrical shocks administered to a muscle that causes the relaxation period between twitches to decrease and the strength of the contraction to increase. In incomplete tetanus, the muscle fibers are stimulated at a high frequency, which leads to a sustained contraction with brief relaxation periods. This results in an increase in the strength of the contraction and a decrease in the relaxation time between twitches.

In the bronchial tree, the total cross-sectional area of each branch level initially decreases for the first 3-4 generations from the trachea. This means that the diameter of the bronchi decreases as the branching occurs. However, after these initial generations, the total cross-sectional area starts to increase and becomes greater than that of the previous branch point. This increase in cross-sectional area allows for a larger surface area for gas exchange in the alveoli, ensuring efficient oxygenation of the blood.

The correct answer is 150-200 ml. The conducting zone of the respiratory system, which includes the first 16 generations of branching, contains smooth muscle, cilia, and mucus-secreting cells. It also contains a certain amount of dead space air, which refers to the air that remains in the conducting zone and does not reach the respiratory zone where gas exchange occurs. On average, this dead space air in the conducting zone is about 150-200 ml.

Turbulence increases the resistance to airflow so A is correct and B is incorrect. C would be correct if it read: Turbulence INCREASES as airflow velocity increases

The correct metabolic equation for internal respiration is C6H12O6 + 6 O2 --> 6 CO2 + 6 H2O + ATP. This equation represents the process of cellular respiration, where glucose (C6H12O6) and oxygen (O2) are converted into carbon dioxide (CO2), water (H2O), and ATP (energy). This equation accurately reflects the products and reactants involved in the metabolic process of internal respiration.

A control system that acts as a switch to turn on and is considered an "open loop." This suggests that the control system does not rely on feedback from the output to adjust its behavior. Instead, it operates based on predetermined inputs and does not make any corrections based on the actual output. This type of control system is known as feed forward, as it only considers the input and does not take into account the output or any feedback information.

An extremely obese person is more likely to have problems breathing when laying down because their diaphragm is too long. The diaphragm is a muscle located beneath the lungs that helps in the process of breathing. In obese individuals, excess fat accumulation in the abdomen can push the diaphragm upwards, reducing its ability to expand and contract properly. This can lead to difficulties in taking deep breaths while lying down, causing problems with breathing.

During pregnancy, the mother's body needs to supply oxygen and nutrients to the fetus, which requires an increase in blood flow. To accommodate this, the body adds another resistance bed in parallel, which refers to the blood vessels in the placenta. This additional resistance bed causes a decrease in total peripheral resistance (TPR), which is the resistance to blood flow in the systemic circulation. As a result, the mother will experience a drop in blood pressure.

Cardiac muscle is the correct answer because it is designed to function at a shorter length than its optimal length. Unlike skeletal muscle, which requires a certain length to generate maximum force, cardiac muscle contracts forcefully even when it is stretched. This property allows the heart to pump blood efficiently, as it can contract forcefully even when the heart chambers are filled with blood. Smooth muscle, on the other hand, can also function at shorter lengths, but it is not as efficient or powerful as cardiac muscle.

Skeletal muscle serves as a pump for both lymph and air. Skeletal muscles are responsible for the movement of lymph, which is a clear fluid that circulates throughout the body and helps remove waste products and toxins. Additionally, skeletal muscles also play a crucial role in breathing by contracting and relaxing to facilitate the movement of air in and out of the lungs. Therefore, the correct answer is that skeletal muscle acts as a pump for both lymph and air.