Physiology Lab Quizzes (Exam 2)

In response to an acute physiological stress, our body initiates a series of activities to maintain homeostasis. Which of the following tissue(s) initiate the stress response? Choose ONE.

hypothalamus

During which phase of the general adaptation syndrome (GAS) is the risk for physiological harm, such as reduced immunity and increased susceptibility to physical or mental illness, greatest?

exhaustion phase

Based on the stress physiology lab manual, what is the best time to measure heart rate upon submerging a hand and forearm into a cold water (i.e., during a Cold Pressor Test)?

1 minute

During final exams week, James notices he's getting frequent headaches and feels constantly on edge, despite usually managing stress well. Which general adaptation syndrome James is likely experiencing?

Resistant phase

Which structure is common to both the neurally-mediated and endocrine-mediated stress responses?

hypothalamus

Use the marker, cursor, and data pad to calculate heart rate in the following LabChart trace. Choose ONE.

(beats / seconds)*(60 ) = bpm

Which device converts physiological signals into analog electrical signals? Choose ONE.

transducer

During which General Adaptive Syndrome phase, glucocorticoid is released?

resistance phase

Which of the following is an earliest indication of an acute physiological stress response during a Cold Pressor Test? Choose ONE.

Increased heart rate

Randy is rock climbing in Yosemite National Park when he falls from the face of the mountain. Luckily, at the last minute he reaches out and grabs hold of the edge of a rock with his right hand. Based on the properties of skeletal muscle only (not connective tissue or bone), will Randy be able to produce more force to pull himself up if his arm is fully extended or partially flexed? Choose ONE.

partially flexed

The force exerted by a muscle is dependent on two factors, one of which is the number of activated motor units. What is this known as? Choose ONE.

recruitment

If a drug reduced the frequency of action potentials, what is another way our nervous system control force production in a muscle in vivo? Choose ONE.

recruitment

Why does the force of a tetanic contraction greater than that of a twitch contraction? This is because:

More Ca2+ is released in a tetanic contraction.

The decrease in active force that occurs at lengths longer than the optimal length is caused by:

insufficient overlap of actin and myosin filaments.

At the neuromuscular junction, the somatic motor neuron releases a neurotransmitter that acts upon on the skeletal muscle to initiate contraction. What type of neurotransmitter receptor is on the skeletal muscle? Choose ONE.

nicotinic cholinergic

Calcium release to cytoplasm of skeletal muscle cells is an important step in generating muscle contraction. What is the immediate step leading to calcium release?

Activation of RyR channels occurs in sarcoplasmic reticulum

You are testing the effects of apnea and cold on the MDR. Would apnea alone produces the same magnitude of effect on heart rate compared to combining these stimuli? Choose ONE.

No. Heart rate would be lowest in the apnea and cold conditions

The effect of the sympathetic nervous system during mammalian dive reflex is through increase the release of __________, causing ______________in the limb, skin, intestines, and kidneys. Choose ONE.

norepinephrine, vasoconstrict

Other than bradycardia, what physiological response is characteristic of mammalian dive reflex? Choose ONE.

peripheral vasoconstriction

Why did you want to normalize the data in the Mammalian Dive Reflex experiment? Choose ONE.

Because of our research question.

How does the autonomic nervous system produce bradycardia during the MDR? Choose ONE

It increases parasympathetic activity.

Imagine you had tested 64 subjects, divided into four groups so that 16 subjects were assigned to each of the four conditions (no apnea, apnea alone, cold alone, and apnea plus cold). What type of study design would this be? Choose ONE.

randomized control

In the experiment described above, what type of statistical test would be MOST appropriate? Choose ONE.

one-way ANOVA

The Chicago Bulls basketball team has arrived in Denver for a game against the Nuggets. Prior to the game, the athletes breathe 100% oxygen for 10 minutes. What sensor(s) detect(s) the change in partial pressure of O2 in these athletes? Choose ONE.

peripheral chemoreceptors

What will happen to activity of neurons in the respiratory control center if blood oxygen levels decrease or carbon dioxide levels increase? Choose ONE.

Activity will increase.