Autonomic Nervous System and CVP function

Question 1

What are the two main divisions of the autonomic nervous system involved in controlling blood pressure?

Answer 1

Sympathetic and parasympathetic nervous systems.

Question 2

How does the sympathetic nervous system affect blood pressure?

Answer 2

It increases heart rate (positive chronotropy) and contractility (positive inotropy), leading to increased cardiac output and higher blood pressure.

Question 3

What is the role of the parasympathetic nervous system in blood pressure regulation?

Answer 3

It decreases heart rate and contractility, which lowers stroke volume and cardiac output, resulting in decreased blood pressure.

Question 4

What is the primary function of the cardiovascular system?

Answer 4

To provide perfusion by delivering oxygenated blood to tissues.

Question 5

What are the determinants of blood pressure?

Answer 5

Cardiac output (stroke volume and heart rate), peripheral vascular resistance, blood volume, blood viscosity, and elasticity of blood vessel walls.

Question 6

What is the relationship between stroke volume and blood pressure?

Answer 6

An increase in stroke volume leads to an increase in blood pressure.

Question 7

How does peripheral vascular resistance affect blood pressure?

Answer 7

Higher peripheral vascular resistance (vasoconstriction) increases blood pressure, while lower resistance (vasodilation) decreases blood pressure.

Question 8

What centers in the medulla control the sympathetic and parasympathetic nervous systems?

Answer 8

The cardiac accelerator center (activates sympathetic) and the cardiac inhibitory center (activates parasympathetic).

Question 9

Where are baroreceptors located, and what is their function?

Answer 9

Baroreceptors are located in the carotid sinus and aortic arch, and they sense blood pressure changes.

Question 10

What happens to baroreceptor firing when blood pressure increases?

Answer 10

The firing rate of baroreceptors increases with higher blood pressure, which sends signals to the central nervous system to adjust blood pressure accordingly.

Question 11

Describe the response of the autonomic nervous system to decreased blood pressure.

Answer 11

Baroreceptor firing decreases, leading to reduced parasympathetic activity (increased heart rate) and increased sympathetic activity (vasoconstriction), raising blood pressure.

Question 12

Describe the response of the autonomic nervous system to increased blood pressure.

Answer 12

Baroreceptor firing increases, activating the parasympathetic system (decreasing heart rate and contractility) and inhibiting the sympathetic system (reducing peripheral resistance), lowering blood pressure.

Question 13

What is perfusion, and why is it important?

Answer 13

Perfusion is the delivery of oxygenated blood to tissues; it’s essential for maintaining cellular function and overall health.

Question 14

What is the role of the vagus nerve in heart regulation?

Answer 14

The vagus nerve activates the parasympathetic nervous system, which decreases heart rate and contractility.

Question 15

What is the normal body temperature range for humans?

Answer 15

97 to 99 degrees Fahrenheit (approximately 36.1 to 37.2 degrees Celsius).

Question 16

Why is it crucial to maintain body temperature within the normal range?

Answer 16

It ensures that normal metabolism occurs and that the body functions adequately.

Question 17

What happens to the body if thermoregulation fails?

Answer 17

The body may not function properly and can ultimately lead to expiration.

Question 18

What are thermoreceptors and what is their role?

Answer 18

Thermoreceptors sense changes in body temperature and compare it to the set point in the hypothalamus.

Question 19

Where are thermoreceptors located in the body?

Answer 19

In the skin and the preoptic area of the hypothalamus.

Question 20

What is the function of warm-sensitive neurons in the hypothalamus?

Answer 20

They activate the parasympathetic system to cause vasodilation and activate sweat glands, promoting heat dissipation.

Question 21

How do cold-sensitive neurons in the hypothalamus respond to decreased body temperature?

Answer 21

They activate the sympathetic system to cause vasoconstriction, minimizing heat loss.

Question 22

Describe the response when body temperature increases above the hypothalamic set point.

Answer 22

The heat-loss center is activated, leading to dilation of skin blood vessels and activation of sweat glands, which dissipates heat.

Question 23

What occurs when body temperature decreases below the hypothalamic set point?

Answer 23

The heat-promoting center is activated, causing constriction of skin blood vessels and activation of skeletal muscles to generate heat (shivering).

Question 24

What are the two main centers in the hypothalamus that regulate body temperature?

Answer 24

The heat-loss center and the heat-promoting center.

Question 25

How does the body respond to fever?

Answer 25

The body temperature rises above normal, and mechanisms for heat dissipation may be impaired, leading to decreased overall function.

Question 26

What role does the preoptic area of the hypothalamus play in thermoregulation?

Answer 26

It contains thermoreceptors that help compare the body’s temperature with the hypothalamic set point.

Question 27

What physiological changes occur during shivering?

Answer 27

Skeletal muscles are activated to generate heat, increasing body temperature back to normal.

Question 28

What mechanism helps to cool the body down during excessive heat?

Answer 28

Sweating and vasodilation of blood vessels help dissipate heat.

Question 29

What is the primary function of energy systems in the body?

Answer 29

To provide ATP for daily activities and physiological processes.

Question 30

What are the two main factors involved in energy homeostasis?

Answer 30

Energy intake (food consumption) and energy expenditure (physiological processes and exercise).

Question 31

Which two systems primarily control energy metabolism?

Answer 31

Hormonal systems and neural systems.

Question 32

How does glucose play a role in energy metabolism?

Answer 32

Glucose is a key determinant of energy intake and output, influencing feeding behavior and energy expenditure.

Question 33

What happens to glucose after food is ingested?

Answer 33

It is absorbed into the GI tract, enters circulation, and is sent to the liver for glucose production.

Question 34

What role do incretins play in glucose metabolism?

Answer 34

Incretins stimulate the release of insulin in two phases, suppressing glucose production and inhibiting glucagon release.

Question 35

What is the traditional view of food intake regulation?

Answer 35

Controlled primarily by glucoreceptors comparing arterial and venous blood glucose levels.

Question 36

What is the contemporary view of energy balance in the body?

Answer 36

A complex network involving multiple systems, particularly the arcuate nucleus of the hypothalamus.

Question 37

What are orexigenic neurons, and what do they do?

Answer 37

Appetite stimulants in the arcuate nucleus, including Neuropeptide Y (NPY) and Agouti-related Peptide (AgRP).

Question 38

What are anorexigenic neurons and their function?

Answer 38

Appetite suppressants controlled by Proopiomelanocortin (POMC), leading to reduced feeding behavior.

Question 39

Which hormones influence the activity of orexigenic and anorexigenic neurons?

Answer 39

Leptin, PYY, ghrelin, and insulin.

Question 40

What role does leptin play in energy metabolism?

Answer 40

It reduces feeding behavior and helps inhibit obesity.

Question 41

How does exercise affect appetite and energy metabolism?

Answer 41

Acute exercise can temporarily suppress appetite and decrease ghrelin levels while increasing PYY levels.

Question 42

What is the effect of exercise on insulin resistance?

Answer 42

Exercise reduces insulin resistance, improving glucose metabolism.

Question 43

What is the role of Brain-Derived Neurotrophic Factor (BDNF) in exercise?

Answer 43

BDNF plays a crucial role in memory and learning, which is enhanced by exercise.

Question 44

How does aerobic exercise impact motor learning, according to research?

Answer 44

Aerobic exercise post-practice can improve performance and reduce error in motor tasks over time.

Question 45

Why is it important for physical therapists to understand energy metabolism?

Answer 45

They can educate and modify environmental and individual factors affecting patients’ energy intake and expenditure.

Question 46

What metabolic disorders can arise from energy metabolism failures?

Answer 46

Obesity and type II diabetes mellitus.