CH 2 Temperature

Question 1

Balance between the heat produced or acquired by the body and the amount lost

Answer 1

Body temperature

Question 2

Warm-blooded

Answer 2

Homoiothermic

Question 3

Cold-blooded

Answer 3

Poikilothermic

Question 4

To maintain a relatively constant internal body temperature; monitors and acts to maintain temperatures that are optimal for normal cellular and vital organ function

Answer 4

Purpose of Thermoregulatory System

Question 5

What are the three primary components of the thermoregulatory system?

Answer 5

Thermoreceptors, regulating center, and effector organs

Question 6

Provides input to the hypothalamus

Answer 6

Thermoreceptors

Question 7

Temperature regulating center

Answer 7

Hypothalamus

Question 8

(skin temp); composed primarily of of free nerve endings and have a high distribution in skin

Answer 8

Peripheral Receptors

Question 9

(core temp); located in deep tissues (abdominal), nervous system, and hypothalamus

Answer 9

Central Thermoreceptors

Question 10

Demonstrate a larger distribution of cold receptors than warmth receptors; sensitive to rapid changes in temp

Answer 10

Cutaneous peripheral thermoreceptors

Question 11

Signals enter spinal cord through afferent nerves and travel to the hypothalamus via the lateral spinothalamic tract

Answer 11

Cutaneous peripheral thermoreceptors

Question 12

Sensitive to temperature chages in blood perfusing the hypothalamus; also initiate responses to converse or dissipate heat

Answer 12

Thermoreceptors in hypothalamus

Question 13

Particularly sensitive to core temperature changes and monitoring body warmth; permit feed forward responses to expected changes in core temp

Answer 13

Thermoreceptors in hypothalamus

Question 14

Coordinates heat production and loss processes (like a thermostat)

Answer 14

Hypothalamus

Question 15

Respond and function to increase and dissipate body heat

Answer 15

Effector Organs/Systems

Question 16

What are the primary effector systems?

Answer 16

Vascular, metabolic, skeletal muscle (shivering), and sweating

Question 17

Mechanisms are activated to conserve heat and increase heat production when?

Answer 17

When body temperature is lowered

Question 18

What are the heat conservation and production mechanisms?

Answer 18

Vasoconstriction of blood vessels, decrease of sweat gland, cutis anserina or piloerection (gooseflesh), shivering and hormonal regulation

Question 19

When the hypothalamus activates the sympathetic nerves, resulting in vasoconstriction of cutaneous vessels throughout the body

Answer 19

Vasoconstriction of blood vessels

Question 20

Significantly reduces the lumen of vessels and decreases blood flow near the surface of skin (where blood is normally cooled)- reducing the amount of heat lost

Answer 20

Vasoconstriction of blood vessels

Question 21

To reduce or to prevent heat loss by evaporation

Answer 21

Decrease sweat gland activity

Question 22

Hairs standing on end

Answer 22

Piloerection

Question 23

Goose flesh

Answer 23

Cutis anserina

Question 24

Functions to trap a layer of insulating air near the skin and decrease heat loss in lower mammals with greater hair covering

Answer 24

Cutis Anserina and Piloerection

Question 25

What mechanisms are designed to produce heat when decreased body temp occurs?

Answer 25

Shivering and hormonal regulation

Question 26

Primary motor center for shivering

Answer 26

Posterior hypothalamus

Question 27

Activated by cold signals from the skin and spinal cord

Answer 27

Posterior hypothalamus

Question 28

What can be partially suppressed through conscious cortical control and voluntary muscle activity?

Answer 28

Shivering reflex

Question 29

How does shivering work in response to cold?

Answer 29

Impulses from the hypothalamus activate efferent somatic nervous system causing increased tone of skeletal muscles to increase to a certain threshold level

Question 30

Function in thermal regulation is to increase cellular metabolism, which increases the body heat

Answer 30

Hormonal influences

Question 31

When increased metabolism occurs through circulation of hormones from the adrenal medulla: norepinephrine and epinephrine is called what?

Answer 31

Chemical Thermogenesis

Question 32

What is more important in infants than adults because hormones increase heat by 100% compared to 10-15% in adults?

Answer 32

Chemical Thermogenesis

Question 33

4 primary methods to dissipate excess heat from the body

Answer 33

Radiation, conduction, convection, and evaporation

Question 34

Transfer of heat by electromagnetic waves from one object to another accomplished by radiation

Answer 34

Radiation

Question 35

Heat transfer occurs through the air between objects not in direct contact; heat lost to surrounding objects that are colder than the body

Answer 35

Radiation

Question 36

Transfer of heat from one object to another through a liquid, solid or gas

Answer 36

Conduction

Question 37

This type of heat transfer requires direct contact between two objects; heat lost by conduction to air

Answer 37

Conduction

Question 38

Transfer of heat by movement of air or liquid (water)

Answer 38

Convection

Question 39

Accomplished secondary to conduction

Answer 39

Convection

Question 40

Heat loss is most effective when air or liquid surrounding the body is continually moved away and replaced

Answer 40

Convection

Question 41

Heat is conducted to the air, then air is moved away from the body by currents

Answer 41

Convection

Question 42

Dissipation of body heat by conversion of a liquid to a vapor

Answer 42

Evaporation

Question 43

Heat loss occurs on a continual basis through the respiratory tract and through perspiration of skin

Answer 43

Evaporation

Question 44

Provides major mechanism of heat loss during exercise

Answer 44

Evaporation

Question 45

Elevation of normal body temperature- commonly known as fever

Answer 45

Pyrexia

Question 46

Occurs when the "set" value of the hypothalamic thermostat is triggered to rise by circulating pyrogens secreted from toxic bacteria, viruses, and injured body tissue

Answer 46

Fever

Question 47

Signs and symptoms: general malaise, headache, increased pulse and respiratory rate, chills, piloerection, shivering, loss of appetite, skin flushes and hot to touch, nausea, irritability, restlessness, constipation, sweating, thirst, coated tongue, decreased urinary output, weakness, insomia

Answer 47

Signs and symptoms of fever

Question 48

Period of fever that occurs just prior to onset; symptoms: slight headache, muscle aches, general malaise, or loss of appetite

Answer 48

Prodromal

Question 49

Period of fever from either gradual or sudden rise until the maximum temperature is reached

Answer 49

Phase one fever: onset

Question 50

Symptoms of phase one fever: onset?

Answer 50

Chills, shivering, and pale appearance of skin

Question 51

Which fever phase? As body temp is raised, vasoconstriction moves blood to the interior of the body to retain heat; the skin becomes cool and shivering is initiated to produce more heat

Answer 51

Phase one fever: onset

Question 52

Which phase of fever attempts to preserve and produce heat continue until a new, higher temp is reached

Answer 52

Phase one fever: onset

Question 53

Period of fever that is the point of highest elevation of fever

Answer 53

Phase two fever: course

Question 54

Which phase of fever remains relatively stable once the higher temp is reached?

Answer 54

Phase two fever: course

Question 55

Which phase of fever is when heat production and heat loss are equal so the shivering stops?

Answer 55

Phase two fever: course

Question 56

Which phase of fever has skin warm to the touch and appearing flushed?

Answer 56

Phase two fever: course

Question 57

Which phase of fever occurs when the fever subsides and temp lowers until normal?

Answer 57

Phase three fever: Termination

Question 58

Which phase of fever has vasodilation occurring and sweating to help cool the body?

Answer 58

Phase three fever: Termination

Question 59

What are the types of fevers?

Answer 59

Continuous, intermittent, relapsing, remittent

Question 60

What type of fever is when body temp is constantly elevated above normal throughout day but does not fluctuate more than 1.8*F

Answer 60

Continuous (constant, sustained) fever

Question 61

What type of fever is seen in uncomplicated minor infection, UTI, lobar pneumonia,typhoid (foodborne illness), infective endocarditis, typhus (flea-borne disease)

Answer 61

Continuous (constant, sustained) fever