Physiology: Homeostasis Flashcards
(144 cards)
1
Q
Internal environment
A
ECF
2
Q
Mileu interior
A
ECF
3
Q
__% of the human body is body fluid
A
60%
4
Q
two major compartments where total body water is distributed
A
intracellular fluid (ICF) and extracellular fluid (ECF)
5
Q
___ of the fluid is inside cells (intracellular fluid)
A
2/3
6
Q
___ of fluid is found in spaces outside the cells (extracellular fluid)
A
1/3
7
Q
Percentage of ECF composition
A
80% interstitial fluid 20% blood plasma
8
Q
surround the cells and makes up ¾ of the ECF volume
A
Interstitial fluids
9
Q
blood plasma is contained in what compartment
A
ECF: intravascular
10
Q
accumulation of fluid in the peritoneal cavity of individuals with liver disease
A
ascites
11
Q
Who first articulated the ECF as the internal environments
A
Claude Bernard, a French physiologist
12
Q
“The environment within”
A
Mileu interior/ECF/Internal environment
13
Q
He recognized that the organ systems of the body are designed and functioned to maintain a constant milieu interior (“constant internal environment”
A
Claude Bernard
14
Q
T/F, All cells live in the same environment (ECF)
A
True
15
Q
T/F, inorder for cell to function, it requires the proper concentration of oxygen, glucose, ions, amino acids, fatty substances and other constituents available in its internal environment (ECF)
A
true
16
Q
ECF/ ICF, Contains large amounts of sodium, chloride and bicarbonate ions
A
ECF
17
Q
ECF/ ICF, contains Large amounts of potassium, magnesium and phosphate ions
A
ICF
18
Q
ECF/ ICF, contains Nutrients for cells (oxygen, glucose, fatty acids, amino acids)
A
ECF
19
Q
ECF/ICF, transports Carbon dioxide and other waste products (kidneys and lungs)
A
ECF
20
Q
Maintenance of nearly constant conditions in the internal environment
A
Homeostasis
21
Q
The tendency of our body to achieve a relatively stable equilibrium between interdependent elements
A
Homeostasis
22
Q
provide oxygen to the extracellular fluid in order to replenish the oxygen that are used by the cells
A
Lungs
23
Q
responsible for maintaining constant ion concentration
A
Kidneys
24
Q
contribute to homeostasis by providing nutrients so that when cells use up the nutrients that are found in the ECF they will now be replenished from the nutrients that have been absorbed by the gastrointestinal tract
A
GI tract
25
T/F, Each organ system will have a role in the maintenance of homeostasis
True
26
T/F, different organ systems will work together in order to return your body to the steady state in case there is a stimulus that disrupts this balance
True
27
Detects change that causes imbalance to the homeostasis
receptor
28
Pathway where receptor sends signal toward control center
afferent pathway
29
process the information that has been sent and give a command
Control center of the nervous system
30
Pathway where control center send the command towards effector
efferent pathway
31
Aim of the command/response sent by the NS to the effector cell
reduce the effect of the disrupting stimulus in order to return your body to the homeostatic level or to the balanced level
32
Describe general process when a state of imbalance occurs
1. Stimulus produces change in variable 2. Receptor detects changes 3. Input: Information sent along afferent pathway to control center 4. Output: Information sent along efferent pathway to effector 5. Reduce effect of stimulus and return body to balance level
33
2 Stages in ECF Transport
1. Movement of blood through the body in the blood vessels 2. Movement of fluids between the blood capillaries and the intracellular spaces between the tissue cells
34
the smallest blood vessel, they are the ones that would be located closest to the cells and also to the intercellular spaces
Capillaries
35
T/F, continual exchange of extracellular fluid occurring between the blood plasma and the interstitial space will happen as blood pass thru capillaries
true
36
T/F, The walls of these capillaries are permeable to most molecules
true
37
T/F, The molecules can go in and out of these capillaries because of their size
false, permeability
38
The process of diffusion is going to be caused by?
Kinetic motion of molecules
39
refers to the state where in fluid and dissolved molecules are continuously moving and bouncing in all directions within the plasma and the fluid in the interstitial space and the capillary space
Kinetic motion
40
ensures the diffusion of substances from the capillary to the cell within a few seconds
distance of capillary to cell
41
T/F, both that of plasma and that of the interstitial fluid is continuously being mixed hence they appear homogenous
true
42
sources of nutrients and substances necessary for the functioning?
o Respiratory system o Gastrointestinal tract o Liver and other metabolic organs o Musculoskeletal system
43
The function of respiratory system will be in coordination with what system
circulatory system
44
The final destination of oxygen in the respiratory tract
alveoli
45
Oxygenated blood is found in?
arteries
46
unoxygenated blood is found in?
veins
47
T/F, Each time blood passes through the body, it also flows through the lungs
True
48
organ that changes the composition of absorbed substances into more usable forms
Liver
49
They help modify the absorbed substances or store them until needed
Liver, Fat cells, GI mucosa, kidneys and endocrine glands
50
Provide motility for protection against adverse surroundings and obtain food & nutrients
Musculoskeletal System
51
Systems responsible for REMOVAL OF METABOLIC WASTE PRODUCT
Lungs Kidneys GI Liver
52
T/F, removal of carbon dioxide occurs at the same time blood picks up oxygen in the lungs, carbon dioxide is released from the blood into the lung alveoli
true
53
Part of kidney responsible for the reabsorption of Glucose, Amino acids, water and ions
Renal tubule
54
End product of poorly absorbed substance in the kidney
Urea
55
A consequences due to the accumulation of metabolic waste products
Disease states
56
It secretes many of these wastes into the bile and eventually in the feces
Liver
57
Organs responsible for the removal of waste products in the body
Lung, Kidney, GI tract, Liver
58
Main systems that regulate body functions
Nervous system, Hormonal system, Reproductive system
59
3 major part of the nervous system
Sensory input CNS Motor output
60
detect state of the body and surroundings
Sensory input
61
Is where sensory input is integrated for processing
CNS
62
Part of CNS where it store information, generate thoughts, determine reactions
Brain and Spinal cord
63
Part of NS in which command is carried out
Motor output
64
It operates subconsciously and controls functions of many internal organs
ANS
65
important in generating new beings to help take place those that are dying
Reproductive system
66
regulates metabolic function and complements the nervous system
Hormonal system
67
Hormone that control glucose metabolism
Insulin
68
Hormone that control sodium ion, potassium ion, and protein metabolism
adrenocortical hormone
69
Hormone that increase rate of chemical reactions in the cell & metabolic functions (act on other organs)
Thyroid hormone
70
Hormone that act on bone to control calcium and phosphate levels; control calcium reabsorption in bone
Parathyroid hormone
71
It stimulates hormones (TSH \> controls thyroid gland)
Pituitary gland
72
The most intricate control system that would operate in all cells to help control intracellular and extracellular functions.
genetic control system
73
operates in association with nervous system in order to control the carbon dioxide concentration in the extracellular fluid
Respiratory system
74
They coordinate to regulate concentration of glucose in ECF
Liver and pancreas
75
regulate the concentration of different ions and substances like hydrogen, sodium, potassium, phosphate and other ions in ECF
Kidneys
76
T/F, The mechanism of oxygen buffering actually depends on the chemical characteristic of hemoglobin.
True
77
T/F, if there is already too much oxygen that is present, hemoglobin having strong affinity to oxygen would not immediately release oxygen in tissues
true
78
T/F, if oxygen concentration in the tissue fluid is too high then it would release sufficient oxygen levels
false, it will not release
79
major product of oxidative reaction of cells
Carbon dioxide
80
T/F, Higher than normal carbon dioxide concentration excites the respiratory center.
true
81
T/F, Elevated carbon dioxide concentration is very dangerous because it can stop the production of energy in the body
true
82
T/F, Hyperventilation is a consequence of elevated CO2 in the blood
true
83
Stretch receptors
Baroreceptors
84
How baroreceptor works when BP is elevated?
arterial pressure rises too high, baroreceptors will send nerve impulses to medulla of brain, decreasing the impulses that would be sent from medulla to the blood vessel causing relaxation of blood vessel and a decrease in blood pressure.
85
How baroreceptor works when BP is too low?
Stretch receptors relaxes, allowing vasomotor center to become more active than usual. This causes vasoconstriction and increased heart pumping.
86
Site of the vasomotor center
Medulla
87
Normal value for Oxygen
40 (35-45) mmhg
88
Normal value for CO2
40 (35-45) mmhg
89
Normal value for Sodium ion
142 (138-146) mmhg
90
Normal value for Potassium ion
4.2 (3.8-5.0)
91
Normal value for calcium ion
102 (1.0-1.4)
92
Normal value for chloride ion
106 (103-112)mmhg
93
Normal value for Bicarbonate ion
24 (24-32)
94
Normal value for glucose
90 (75-95)
95
Normal body temperature
37C/98.4F (98-98.8 F)
96
Normal acid base balance
7.4 (7.37.5)
97
increase in body temperature more than 11F or 7C, will lead to ?
vicious cycle of increasing cellular metabolism that can destroy the cell
98
very high potassium levels can cause
abnormality in cardiac contraction
99
very low potassium concentration can cause
paralysis as a result of inability of nerves to carry signals.
100
fall to more than half of the normal level of calcium could cause
tetanic contraction of the muscles
101
less than half concentration of glucose could cause
mental irritability and sometimes convulsions
102
Cycle in which the output of a system “feed backs” or communicates back to either modify or reinforce the action taken by the system
FEEDBACK MECHANISMS
103
The single objective of feedback mechanism is
maintaining balance or homeostasis
104
FEEDBACK MECHANISMS may operate at what levels
o Tissue level o Organ level o System level o Body level, integrating other organ systems
105
Components of Feedback System
o Sensor or receptor o Integrator o Effector
106
detects specific changes in the environment
Sensor or receptor
107
act to direct impulses to the place where response can be made
Integrator
108
performs the appropriate response
Effector
109
Mechanism that maintains a factor at some mean value
NEGATIVE FEEDBACK
110
Reverse a change and Restore abnormal values to normal
NEGATIVE FEEDBACK
111
How negative feedback system works?
Stimulus-\>imbalance --\>Detected by receptor/sensor--\>Input set via afferent pathway--\>Control center--\>output sent via efferent pathway--\>effector--\>response--\>return to balance
112
Examples of Negative feedback system
o Regulation of CO2 concentration o Blood Pressure Regulation Through Negative Feedback Mechanism o Thyroid Hormone Regulation Through Negative Feedback Mechanism o Thermoregulation
113
The major mechanisms of compensation in shock is
NEGATIVE FEEDBACK
114
Signs and symptoms of shock include
systolic blood pressure less than 90 mmHg; hypotension; rapid resting heart rate; weak rapid pulse; clammy, cool, pale skin; sweating; altered mental state; decreased urinary output; thirst; and acidosis
115
Explain how Thyroid Hormone Regulation Through Negative Feedback Mechanism
The thyrotropin releasing hormone (TRH) --\>stimulate anterior pituitary gland--\>thyroid stimulating hormone (TSH) --\>stimulate the gland to secrete thyroid hormones. High levels of T; negative feedback --\>anterior pituitary & hypothalamus--\>decrease the levels of released TRH --\>decrease the levels of the TSH--\>decrease the levels of thyroid hormones.
116
Hypothyroidism: \_\_\_TSH
High
117
Hyperthyroidism: \_\_\_TSH
Low
118
T/F, In hypothyroid patient, hypothalamus is stimulated to release TRH; there is increased TSH to try to compensate for low thyroid hormones
True
119
T/F, In hyperthyroid patient, negative feedback will be sent to decrease TRH and TSH
True
120
Receptors in thermoregulation
Thermoreceptor in skin and hypothalamus
121
Integrators in thermoregulation
Control centers (preoptic area and heat promoting center in hypothalamus, and hypothalamic neurosecretory cells)
122
Effectors in thermoregulation
Vasoconstriction, increased cellular metabolism, shivering, increased metabolic rate
123
What is stimulated in the anterior pituitary gland to release TSH?
Thyrotrophs
124
How vasoconstrictions works in thermoregulation?
decreases flow of warm blood, and thus transfer of heat from the internal organs to the skin;
125
stimulated release of ___ and _____ increases cellular metabolism which increases heat production;
epinephrine and norepinephrine
126
repetitive muscle contraction that produce heat
shivering
127
increased levels of _____ slowly increase metabolic rate which then rises the body temperature.
thyroid hormones
128
Strengthens or reinforces a change and Produces a “vicious cycle”
Positive Feedback
129
T/F, A mild degree of positive feedback can be overcome by the negative feedback control mechanisms of the body
true
130
T/F, positive feedback may promote instability leading to development of diseases
true
131
Example of positive feedback in the body
Action potential Blood clot formation Parturition Release of calcium Sexual arousal LH surge
132
How AP works in positive feedback
Membrane of a nerve fiber is stimulated--\>Leakage of sodium ions through sodium channels--\>Sodium in the interior of the nerve fiber--\>Change in membrane potential--\>Opening of more channels--\>Sodium entering cells--\>Creates nerve action potential--\>Flow of electrical currents--\>Further initiates additional action potential
133
How blood clot formation works in positive feedback
Rupture of blood clot--\>Formation of primary plug--\>Activation of clotting factors--\>Secondary plug formation
134
Why is blood clot formation needs to be regulated?
Pathological blood clot --\> thrombus --\> causes Myocardial infarction/Heart Attack
135
How Parturition works in positive feedback
Uterine contractions become strong enough--\> stretch of cervix send signals through uterine muscles back to the body of uterus --\>more powerful contractions If powerful enough= baby will be born; if not=will stop and repeat
136
What is the positive feedback of estrogen on the anterior pituitary?
surge of luteinizing hormone (LH) just before ovulation
137
Degree of effectiveness with which a control system maintains constant conditions is determined by ?
gain of negative feedback.
138
Interconnected control mechanisms
Adaptive Control
139
Types of adaptive control
o Simple feedback systems o Complex feedback systems
140
Mechanism is used when movements of the body occur so rapidly that there is not enough time for nerve signals to travel from the peripheral parts of the body all the way to the brain and then back to the periphery again to control the movement
FEED-FORWARD CONTROL
141
Process of FEED-FORWARD CONTROL
Sensory nerve signals from moving parts of the periphery appraise the brain if movement is done correctly Sends corrected signals on the next movement If further correction is need, done on the next movement.
142
T/F, adaptive control occurs in Delayed negative feedback
true
143
Negative vs Positive feedback
144
Computation for gain
