Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Principles > Physiology > Flashcards

Physiology Flashcards

1
Q

Organs are made up of how many types of primary tissues that function together to form a particular function?

A

Two or more types of primary tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a body system?

A

A group of organs that perform related functions and work together to achieve common goals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is essential for normal cell and body function?

A

A stable internal environment called ‘homeostasis’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What type of homeostatic mechanisms cause disease?

A

Deficient, inappropriate or excessive homeostatic mechanisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

In order to maintain homeostasis, a control system must be able to:

A
  • sense deviations from normal in the internal environment that need to be held within narrow limits
  • integrate this information with other relevant information
  • make appropriate adjustments in order to restore a controlled variable to its desired value
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Homeostatic control systems are grouped into two classes:

A

Intrinsic controls and extrinsic controls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Intrinsic controls

A

Local controls that are inherent in an organ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Extrinsic controls

A

Regulatory mechanisms initiated outside an organ and are accomplished by nervous and endocrine systems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Feedforward

A

A term used for responses made in anticipation of a change. It usually acts in combination with negative feedback

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Feedback

A

Refers to responses made after a change has been detected

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Positive feedback

A

Amplifies an initial change (uterine contractions during labour become increasingly stronger until the birth of a baby)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Negative feedback systems

A

Oppose an initial change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Negative feedback promotes..?

A

Stability by regulation of a controlled variable through flow of information along a closed loop

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is blood pressure?

A

The outwards pressure exerted by the blood vessel walls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How can systemic arterial blood pressure be expressed?

A

By systolic and diastolic blood pressures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is arterial blood pressure?

A

The pressure exerted on the walls of the aorta and systemic arteries when the heart contracts. Usually under 140

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the diastolic arterial blood pressure?

A

The pressure exerted by the blood on the walls of the aorta and systemic arterial when the heart relaxes. Normally under 90mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Hypertension

A

A clinical blood pressure of over 140/90 and a day time average of over 135/85

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Pulse pressure

A

The difference between the systolic and diastolic blood pressure. Normally between 30 and 50mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Mean Arterial blood pressure

A

The average arterial blood pressure during a single cardiac cycle which involves the contraction and relaxation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Why is the MAP not obtained by averaging the systolic and diastolic pressures?

A

Because the diastolic portion of the cardiac cycle is twice as long as the systolic portion of the cardiac cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How to calculate MAP (more complicated)

A

MAP = (2x diastolic +systolic) divided by three

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How to calculate the MAP (easier)

A

MAP = DBP + 1/3 pulse pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Normal range of MAP

A

Between 70 and 105 mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are baroreceptors?

A

They are receptors sensitive to changes in pressure and stretch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the sensors in the baroreceptor reflex?

A

Baroreceptor afferent neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are afferent neurons?

A

Sensory neurons that carry nerve impulses from sensory stimuli towards the central nervous system and brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Firing rate in baroreceptor afferent neurons…

A

Increases when the mean arterial blood pressure increases

Decreases when the mean arterial blood pressure decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what does the CV control centre do?

A

it receives CVS afferent information, generates vagal outflow to heart and regulates spinal sympathetic neurones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

MAP calculation using cardiac output and SVR

A

MAP = CO x SVR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the cardiac output?

A

The volume of blood pumped by each ventricle of the heart per minute

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How to calculate cardiac output

A

CO = SV x HR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the stroke volume?

A

He volume of blood pumped by each ventricle of the heart per heart beat

34
Q

What is the systemic vascular resistance?

A

The sum of resistance in all vasculature in the systemic circulation. Regulated by vascular smooth muscle

35
Q

Vasomotor tome meaning

A

Vascular smooth muscles are partially constricted at rest

36
Q

What is the vasomotor tone caused by?

A

Tonic discharge of sympathetic nerves resulting in a continuous release of noradrenaline

37
Q

Autothythmicity

A

The heart can beat rhythmically in the absence of the external stimuli

38
Q

Why should vital signs be recorded?

A

They can be valuable when assessing parents and monitoring their deterioration

39
Q

What depends on the need and frequency to monitor vital signs?

A

The individual patient presentation

40
Q

What can supplement clinical vital signs?

A

Special investigations such as blood tests and x-rays

41
Q

Clinical vital signs commonly assessed and recorded?

A

Pulse, blood pressure, temperature, respiratory rate, capillary refill time, oxygen saturation and consciousness

42
Q

Why might a patient with blood loss feel dizzy?

A

Low arterial blood pressure prevents brain from getting normal perfusion and oxygenation which can progress to confusion, lethargy and loss of consciousness with more blood loss

43
Q

Why might a patient with blood loss be breathless?

A

The body is trying to supply more oxygen to tissues

44
Q

Why might a patient with blood loss look pale and have cool, clammy skin?

A

Arterial blood pressure has decreased. Low arterial blood pressure is detected by baroreceptors resulting in sympathetic stimulation and peripheral vasoconstriction. This helps raise SVR and hence right the drop in blood pressure.

45
Q

Why might a patient with blood loss have a fast, regular, but weak pulse?

A

Arterial blood pressure decreases. Low blood pressure is detected by baroreceptors, resulting in increased sympathetic and decreased parasympathetic activity to the heart - both increase heart rate. The pulse is weak due to the loss of blood resulting in low stroke volume

46
Q

What is laminar flow?

A

The flow of fluid when each particle follows a smooth path. The velocity of the fluid is constant at any point in the fluid.

47
Q

Instruments used to estimate arterial blood pressure?

A

Cuff Sphygmomanometer and stethoscope

48
Q

Core body temperature

A

The temperature of structures deep within the body

49
Q

Normothermia

A

The normal core body temperature and is optimum for cellular metabolism and function

50
Q

Increased body temperature

A

Speed up cellular metabolism

51
Q

What does overheating cause?

A

Protein denaturation, nerve malfunction, convulsions and death

52
Q

What does decreased body temperature cause?

A

A slow down in cellular reactions, and may fatally slow down the metabolism

53
Q

Normal range for tympanic temperature (ear temperature)

A

35.5-37.5 degrees Celsius

54
Q

Why not use oral temperature?

A

Affected by consumption of food and drink

55
Q

Heat gain from internal environment?

A

Metabolic heat

56
Q

Heat gain from external environment?

A

Radiation, convection and conduction

57
Q

Heat loss to external environment

A

Convection, conduction, radiation and evaporation

58
Q

What is basal metabolic heat?

A

The minimum amount of energy required to sustain vital body functions and leads to basic level of heat production

59
Q

What hormones can increase the BMR?

A

Adrenaline, thyroxine and noradrenaline

60
Q

What is conduction?

A

Transfer of heat between objects in contact

61
Q

In what way does heat move?

A

From a warmer to a cooler object

62
Q

What does heat conduction depend on?

A

The temperature gradient and thermal conductivity

63
Q

How does the human body maintain its core temperature at a set point?

A

By homeostatic mechanisms involving a negative feedback control system

64
Q

what are neural inputs to the hypothalamus

A

Those from the negative feedback receptors for temperature regulation

65
Q

The hypothalamus role

A

Acts as the body’s thermostat (maintains the temperature at a set point)

66
Q

Anterior hypothalamic centre is activated by what?

A

Activated by warmth

67
Q

where are the central thermoreceptors?

A

in the hypothalamus, abdominal organs, elsewhere

68
Q

where are the peripheral thermoreceptors?

A

in the skin

69
Q

what are the three effectors for the negative feedback: temperature control?

A

skeletal muscles, skin arterioles and sweat glands

70
Q

what is the posterior hypothalamic centre activated by?

A

cold

71
Q

where are endogenous pyrogens released from?

A

from macrophages

72
Q

what are macrophages?

A

a type of phagocytic white blood cell

73
Q

what do endogenous pyrogens stimulate the release of?

A

prostaglandins in the hypothalamus

74
Q

what effect do prostaglandins acting on the hypothalamic thermo-regulatory centre have?

A

they reset the thermostat

75
Q

what will happen to the hypothalamic temperature set point if there is a fever?

A

the set point is raised

76
Q

what effect does raising the set point temperature have?

A

it initiates mechanisms to heat the body to raise the body to the new set point

77
Q

what happens when the body temperature increases to reach the new set point?

A

fever

78
Q

How can the hypothalamic set point be restored to normal?

A

if the pyrogen release is reduced/stopped or the prostaglandin production is decreased/ceased

79
Q

how does the body temperature return to the normal hypothalamic set point?

A

the hypothalamus initiates mechanisms to cool the body (sweating, vasodilation)

80
Q

fever is a result in temperature set point being said to around?

A

38-40 degrees Celsius

81
Q

hyperthermia

A

extreme uncontrolled increase in body temperature due to failure of heat regulating mechanisms

82
Q

hypothermia

A

a drop in body temperature below the required value for cellular metabolism (below 35 degrees)

Principles (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions