Ch. 6 Immunity
Which of the following cells is a part of the innate immune system and specializes in killing virus-infected and cancer cells?
A. Helper T cells
B. B cells
C. Natural Killer (NK) cells
D. Plasma cells
C. Natural Killer (NK) cells
The parasympathetic nervous system is responsible for:
A. Increasing heart rate
B. Initiating fight-or-flight response
C. Resting and digesting functions
D. Activating skeletal muscle reflexes
C. Resting and digesting functions
Which muscle fiber type is most resistant to fatigue?
A. Type IIx
B. Type IIa
C. Type I
C. Type I (slow oxidative)
What is the equation for cardiac output?
A. Blood Pressure × Resistance
B. Heart Rate × Stroke Volume
C. Heart Rate + Stroke Volume
D. Stroke Volume ÷ Heart Rate
B. Heart Rate × Stroke Volume
Which type of white blood cell becomes a macrophage once it enters tissue and helps destroy pathogens?
A. Basophil
B. Monocyte
C.Neutrophil
D. T cell
B. Monocyte
What brain region helps plan and coordinate voluntary movement?
A. Brain stem
B. Cerebellum
C. Motor cortex
D. Thalamus
C. Motor cortex
What is the basic contractile unit of a muscle fiber?
A. Myofibril
B. Sarcomere
C. Sarcolemma
D. Motor unit
B. Sarcomere
At what percentage of VO₂ max does stroke volume typically plateau in untrained individuals?
A. 20–30%
B. 40–60%
C. 70–90%
D. Stroke volume does not plateau in untrained individuals
B. 40–60%
Which chemical is released by phagocytes and contributes to swelling (edema)?
A.Bradykinin
B. Cortisol
C. Histamine
D. IgA
A.Bradykinin
What brain structure is especially involved in exercise-induced improvements in learning and memory?
A. Hippocampus
B. Medulla
C. Occipital lobe
D. Pons
A. Hippocampus
Which type of muscle contraction occurs when force is produced without a change in muscle length?
A. Concentric contraction
B. Eccentric contraction
C. Isotonic contraction
D. Isometric contraction
D. Isometric contraction
What is the relationship between pressure, resistance, and blood flow?
A. Blood Flow = Resistance / ΔPressure
B. Blood Flow = ΔPressure × Resistance
C. Blood Flow = ΔPressure / Resistance
D. Blood Flow = ΔPressure − Resistance
C. Blood Flow = ΔPressure / Resistance
How long does it typically take for immune cell levels to return to normal after a bout of prolonged intense exercise?
A. 30 minutes
B. 1 hour
C. 3–24 hours
D. 48–72 hours
C. 3–24 hours
This proprioceptor detects muscle tension and helps prevent injury by inhibiting overactive muscles.
A. Alpha motor neuron
B. Cerebellum
C. Golgi tendon organ
D. Muscle spindle
C. Golgi tendon organ
What is the term for age-related loss of muscle mass?
A. Atrophy
B. Cachexia
C. Myopathy
D. Sarcopenia
D. Sarcopenia
How does afterload (MAP) affect stroke volume?
A. Higher afterload increases stroke volume by improving venous return
B. Higher afterload inhibits stroke volume by making it harder for the heart to eject blood
C. Higher afterload has no effect on stroke volume
D. Higher afterload enhances contraction strength, increasing stroke volume
B. Higher afterload inhibits stroke volume by making it harder for the heart to eject blood
***DOUDBLE POINTS***
After a long/intense workout, the immune system is suppressed for a few hours. What is this period called?
Open Window
***Double Points***
The withdrawal reflex involves what sequence of events?
A. Brain ➡️ Motor cortex ➡️ Muscle
B. Sensory neuron ➡️ Interneuron ➡️ Alpha motor neuron
C. Vestibular input ➡️ Cerebellum ➡️ Motor neuron
D. Autonomic nerve ➡️ Sympathetic ganglion ➡️ Effector
B. Sensory neuron ➡️ Interneuron ➡️ Alpha motor neuron
*** DOUBLE POINTS***
The sarcomere shortens during contraction because of this theory?
sliding filament theory
*** Double Points ***
What locally produced molecule helps increase blood flow during exercise by causing vasodilation of arterioles?
💡 Hint: It’s a gas released by the endothelium and plays a key role in relaxing smooth muscle.
Nitric oxide