Stress and Homeostasis

Question 1

What is homeostasis?

Answer 1

balanced. maintain stable internal conditions necessary for survival. (goldie locks)

Question 2

What are stressors in the context of homeostasis?

Answer 2

External or internal conditions that challenge homeostasis, requiring the body to adapt.

Question 3

What is the body’s response to stress

Answer 3

Adaptation, which helps restore homeostasis. Failure to adapt leads to illness or death.

Question 4

What is a negative feedback loop in homeostasis?

Answer 4

opposes a change to return the body to a set point (e.g., thermoregulation, blood sugar regulation). Brake petal STOP

Question 5

Give an example of a positive feedback loop

Answer 5

Childbirth: Baby’s head presses on cervix, signals brain to release oxytocin, increases contractions, more pressure on cervix, leading to further contractions.

Question 6

What is the central stress response?

Answer 6

Brain-based response involving arousal, alertness, and inhibition of non-essential functions (e.g., reproduction, growth).

Question 7

What is the peripheral stress response?

Answer 7

Increased respiration, cardiovascular tone, and nutrient distribution to the brain, heart, and skeletal muscles.

Question 8

What are the three phases of the stress response?

Answer 8

1. Alarm 2. Resistance 3. Exhaustion

Question 9

What happens during the alarm phase of stress?

Answer 9

The body detects the stressor and initiates the “fight or flight” response through the hypothalamus.

Question 10

What is the role of the hypothalamus in stress?

Answer 10

The hypothalamus acts as the control center, triggering the stress response by communicating with effectors.

Question 11

What is the HPA axis?

Answer 11

Hypothalamus-Pituitary-Adrenal axis: A system that regulates stress through cortisol production, promoting adaptation to chronic stress.

Question 12

What is the role of cortisol in stress?

Answer 12

A glucocorticoid hormone that increases blood glucose, regulates Na+/K+ balance, and suppresses immune responses during stress.

Question 13

What is the sympatho-adrenal medullary (SAS) system?

Answer 13

A stress response system mediated by the sympathetic nervous system, secreting catecholamines (epinephrine and norepinephrine) for “fight or flight.”

Question 14

What are catecholamines and their role in stress?

Answer 14

Hormones like epinephrine and norepinephrine that increase heart rate, blood pressure, and prepare the body for acute stress.

Question 15

What happens during the exhaustion phase of stress?

Answer 15

body’s compensatory mechanisms fail, leading to potential illness, disability, or death if homeostasis is not restored.

Question 16

What is compensatory reserve in stress?

Answer 16

The body’s ability to maintain homeostasis before its compensatory mechanisms are overwhelmed.

Question 17

What factors affect compensatory reserve?

Answer 17

Age, health status, duration and intensity of the stressor

Question 18

How can clinical management increase compensatory reserve?

Answer 18

By addressing the underlying problem (e.g., stopping blood loss, providing IV fluids, administering vasopressors).

Question 19

What is the function of the autonomic nervous system in stress?

Answer 19

It controls involuntary responses, with the sympathetic division activating the “fight or flight” response and the parasympathetic division promoting rest.

Question 20

What is physiological stress?

Answer 20

Any external or internal condition that challenges the homeostasis of a cell or organism.

Question 21

What is adaptation in response to stress?

Answer 21

body adjusts to restore homeostasis after a stressor.

Question 22

What are the central functions during a stress response?

Answer 22

Arousal, alertness, cognition, and inhibition of non-essential functions like reproduction and growth.

Question 23

What are the peripheral functions during a stress response?

Answer 23

Increased respiration, cardiovascular tone, and nutrient delivery to vital organs (brain, heart, skeletal muscles).

Question 24

What are peripheral chemoreceptors?

Answer 24

Receptors that detect changes in blood pH and help regulate breathing and oxygenation.

Question 25

What is the role of the control center in homeostasis?

Answer 25

It processes information from receptors, compares it to the set point, and stimulates a response to maintain balance.

Question 26

What is the role of the hypothalamus in homeostasis?

Answer 26

It regulates body functions such as temperature, blood pressure, and circadian rhythms through homeostatic mechanisms.

Question 27

What is an effector in homeostasis

Answer 27

An organ or tissue that acts to restore homeostasis in response to signals from the control center.

Question 28

What is the role of the renal tubules in homeostasis?

Answer 28

They reabsorb water and adjust blood osmolality as part of the homeostatic response to dehydration or fluid imbalance.

Question 29

What is a stressor in the context of homeostasis?

Answer 29

Any physical, chemical, or environmental factor that causes a deviation from the body’s normal state.

Question 30

What is the role of receptors in homeostasis?

Answer 30

They detect changes in the environment and forward the information to the control center for processing.

Question 30

What is the role of a negative feedback loop in homeostasis?

Answer 30

It reduces or opposes a change to bring the body back to its set point, maintaining balance.

Question 31

What is the positive feedback loop in homeostasis?

Answer 31

It amplifies or enhances a change, pushing the body further from the set point, often seen in processes like childbirth and blood clotting.

Question 32

What is thermoregulation?

Answer 32

The process by which the body maintains a stable internal temperature, usually through negative feedback mechanisms.

Question 33

How does the body regulate blood glucose?

Answer 33

Insulin lowers blood glucose when high; glucagon raises it when low, both through negative feedback loops.

Question 34

What is the role of epinephrine in the stress response?

Answer 34

It increases heart rate, blood pressure, and energy availability for the "fight or flight" response.

Question 35

What is the role of norepinephrine in the stress response?

Answer 35

It helps maintain blood pressure and enhances the contractility of cardiac muscles during stress.

Question 36

What is the autonomic nervous system's role in stress adaptation?

Answer 36

It regulates involuntary functions, with the sympathetic division activating during stress and the parasympathetic calming the body after.

Question 37

What happens when compensatory mechanisms fail during stress?

Answer 37

The body can no longer maintain homeostasis, leading to illness, disability, or death.

Question 38

How does the body compensate during hemorrhage?

Answer 38

increases heart rate, constricts blood vessels, and redirects blood flow to vital organs to maintain tissue oxygenation.

Question 39

What are glucocorticoids, and how do they function in stress?

Answer 39

Hormones like cortisol that help the body respond to stress by increasing blood glucose and suppressing inflammation.

Question 39

What are vasopressors, and how do they help in stress management?

Answer 39

Medications that constrict blood vessels, raising blood pressure to improve blood flow to vital organs during stress or injury.

Question 40

What role does cortisol play in the stress response?

Answer 40

Cortisol increases blood glucose, regulates immune response, and helps the body manage prolonged stress.

Question 41

What is the "fight or flight" response?

Answer 41

physiological reaction triggered by the sympathetic nervous system that prepares the body to face or escape danger.

Question 42

What is the sympathetic nervous system?

Answer 42

division of the autonomic nervous system that activates the body’s "fight or flight" response during stress.

Question 42

What is the parasympathetic nervous system?

Answer 42

division of the autonomic nervous system that promotes "rest and digest" functions after the stressor has passed.