EXAM 4 Flashcards

1
Q

major nutrients

A

macronutrients: Carbohydrates, lipids, proteins

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2
Q

micronutrients

A

vitamins + minerals

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3
Q

USDA “my plate” guidelines

A

-1/2 fruits and vegetables
-1/2 grains and proteins
glass of milk

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4
Q

there are 45-50 essential nutrients

A

must be in diet for healthy physiology because body doesn’t make enough of it

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5
Q

carbohydrates include

A

-sugars: mono+disaccharides
—-from fruit, milk, and honey
-polyscaccharides: from grains, fruits, and veg

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6
Q

glucose is used by

A

-cells for energy
-red blood cells and neurons rely on it

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7
Q

insoluable polysaccharides

A

-such as cellulose provide fiber that help with intestinal health, defecation
-soluble fibers in some fruit

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8
Q

the most abundant dietary lipid is

A

-triglycerides: neutral fat
-saturated fat (with hydrogen) in meat+ dairy
-unsaturated: olive oils+seeds

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9
Q

essential fatty acids include

A

-e.g. linoleic+ linoleic acids are needed in the diet
–in most vegetable oils

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10
Q

cholesterol is found in

A

-egg yolk, milk, meat
-liver secretions

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11
Q

lipids are used by the body to

A

-cell membrane stability
-myelin in nervous system
-absorption of fat soluble vitamins
-can provide energy storage+ as an energy source in some conditions
-some chemical messengers: prostaglandins
-make adipose: cushioning and insulation

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12
Q

proteins have all essential amino acids are

A

-complete proteins : dairy, meat, fish, soybeans
-vs. incomplete proteins: lack four or more of 8 essential amino acids

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13
Q

incomplete proteins:

A

lack four or more of 8 essential amino acids

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14
Q

amino acids from dietary protein may be used to

A

-synthesize new proteins or be broken down to make energy

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15
Q

conditions that determine how amino acids are used determine

A

weather someone is positive in nitrogen balance or negative

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16
Q

to be positive in nitrogen balance (amino acids)

A

i) all needed amino acids (all 20 of them)
ii) caloric intake of carbs+fats meets energy needs
iii) hormone levels reflect healthy, non stressed states; healthy, low levels of stress hormones and healthy high levels of growth hormones

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17
Q

vitamins mostly serve as

A

coenzymes (assist in catalysis)

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18
Q

Vitamins A,D,E, and K are

exp for vit a

A

-fat soluble
-e.g. vitamin A in rhodopsin in rod’s for night vision

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19
Q

water soluble vitamins include

example of a ws vit

A

B-complex vitamins and vitamin C

folic acid- important for DNA replication in fetal development

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20
Q

water soluble vitamin functions

A

important in DNA replication

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21
Q

minerals such as Ca+ are used by the body to

A

-add strength to bones and teeth
-messengers to influence proteins’ function (eg Ca+ binds to calmodulin in smooth m)
-excitability: Ca+ depolarization of heart cells

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22
Q

metabolic processes are either

A

catabolic: breaking down big molecules
anabolic: building big molecules

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23
Q

catabolic processes

A

breaking down big molecules

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24
Q

anabolic

A

building big molecules

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25
Q

In cellular respiration…

A

food molecules are broken down and their parts are used to make atp

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26
Q

Three stages are involved in processing energy containing nutrients

A

a) GI system digest nutrients and absorbs them
b) convert small nutrient molecules to a form that can be used for energy production
c) aerobic production of energy in mitochondria

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27
Q

oxidation-reduction reactions are coupled reactions that involve

A

-transfer of electrons from one molecule to another
-when O added or H is lost it is oxidized
-a molecule that gains an electron is reduced

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28
Q

in the body, oxidation reduction reactions are enzyme catalyzed

A

-use coenzymes such as FAD and NAD+
-energy from food is transferred to the coenzyme so ATP can be made

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29
Q

ATP synthesis may occur through two mechanisms

A

-substrate-level phosphorylation
-oxidative phosphorylation

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30
Q

substrate-level phosphorylation

A

P transferred from one molecule over to ADP to make ATP

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31
Q

oxidative phosphorylation

uses, pushes

A

-uses electron transport chain in mitochondria
-pushes H+ into intermembrane space
-when H+ diffuses back in energizes the ATP synthase to make ATP

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32
Q

Carbohydrate Metabolism

  1. glucose enters the cell by….
A

-facilitated diffusion when insulin causes glucose transporters to go to membrane

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33
Q

Carbohydrate Metabolism

  1. glucose enters glycolysis

what is it and where does it occur

A

=sugar splitting, happens in cytosol, no O2 needed

3 phases

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34
Q

Glycolysis Phase 1

A

investment of 2 ATP to add phosphate groups to glucose

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35
Q

Glycolysis Phase 2

A

sugar cleavage: the 6-c sugar is split into three carbon fragments

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36
Q

glycolysis phase 3

A

-3 C fragments are oxidized
-ATP is formed (net of 2 ATP for glycolysis)
-NAD+ is reduced to NADH

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37
Q

two pyruvic acids molecules can follow ____ depending on ____

A

two distinct pathways depending on the availability of oxygen

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38
Q

pyruvic acid pathways when there is not enough oxygen

A

pyruvic acid ferments into lactic acid

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39
Q

pyruvic acid pathways when there is adequate oxygen

what (2 things) enters what to start what

A

pyruvic acid and NADH enter mitochondria to start aerobic cellular respiration

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40
Q

in aerobic pathways, pyruvic acid

A

enters mitochondria by active transport

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41
Q

pyruvic acid is first converted to

A

acetyl CoA: One carbon is removed from pyruvate and acetyl CoA is added

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42
Q

Acytyl CoA enters the Krebs Cycle (citric acid cycle)

within…
what combines
what is oxidized

A

-within mitochondrial matrix
-Acetyl acid combines with oxaloacetic acid to form citric acid
-citric acid is then oxidized

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43
Q

the krebs cycle yields (3)

A

2 ATP
NADH, FADH2 (reduced coenzymes)
CO2+H+

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44
Q

the electron transport chain

requires, pushes, then what

A

-requires O2 to take electrons from coenzymes (generates H2O)
-Pushes H+ out of matrix into inter membrane space
-as H+ flows back into matrix, oxidative phosphorylation occurs by ATP synthase

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45
Q

krebs cycle: the net energy gain from one glucose molecule is

A

30 ATP

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46
Q

cells cannot store large amounts of ATP, and so

A

they spend it or save its energy in other forms

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47
Q

glycogenesis

whats created
where and when

A

-creating glycogen from glucose
-occurs in liver and muscle cells when energy levels are high

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48
Q

glycogenolysis

what happens, when

A

-split glycogen to glucose:6P when energy is low; liver cells can remove the P and release glucose to blood

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49
Q

gluconeogenesis

uses what to make what and when

A

-use amino acids or glycerol to make glucose in liver when energy is low

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50
Q

energy content of fat molecules is

A

-very high
-most energy dense type of fuel 9cal/gram

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51
Q

lipolysis

A

-break down T.A.G. with lipase into glycerol and fatty acids
-followed b-oxidation: breaking off 2-c’s at a time of F.A.; add CoA and enter citric acid cycle
-ketone bodies can be a byproduct

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52
Q

Lipogenesis

A

-when energy levels are sufficient, energy can be stored as fat
-TAG is built up from smaller molecules

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53
Q

Protein metabolism; amino acids can be used

  1. to make new proteins
A

-when all neededamino acids are present
-allows ingested and synthesized a.a.’s to build new proteins

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54
Q

Protein metabolism; amino acids can be used

  1. for energy

when?
transamination

A

-when energy levels are low, when stress hormone levels are high, when certain a.a.’s are lacking
-change the amino acid…
–transamination: converts one amino acid into a keto acid
–that keto acid can be modified to enter the citric acid cycle to make ATP
–extra nitrogen can be excreted by kidney at urea

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55
Q

insulin is a key hormone for the…

A

absorptive state= well fed

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56
Q

during the absorptive state __ exceeds __

A

anabolism exceeds catabolism

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57
Q

insulins effect on glucose metabolism

-_ glucose uptake by body cells
-__ glucose oxidation in tissue cells
-__ gluconeogenesis
-__storage of glycogen and conversion of carbohydrates to fat

A

-increase glucose uptake by body cells
-increase glucose oxidation in tissue cells
-decrease gluconeogenesis
-increase storage of glycogen and conversion of carbohydrates to fat

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58
Q

insulins effect on amino acid metabolism

A

-increase transport of amino acids into cells
-increase protein synthesis

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59
Q

insulin contributes to feelings of

A

satiety

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60
Q

nuclei (clusters of cells) in the ___ are crucial for eating

A

hypothalamus

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61
Q

some cells make neurotransmitters or hormones that trigger hunger…

A

when fasting (i.e. in postabsorbative state)
NPy from arcuate nucleus –> increase orexin from lateral hypothalamic area

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62
Q

other cells make neurotransmitters or hormones that trigger satiety…

A

after a big meal
POMC+CART from arcute nucleis-> increase CRH from ventromedial nucleus

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63
Q

short-term regulation of food intake

what for hunger and what for satiety?

A

i) empty stomach secretes ghrelin: hormone that stimulates hunger pathways in brain
ii) full stomach and high blood sugar stimulate vagus nerve and insulin secretion; insulin stimulates satiety pathways in brain

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64
Q

long-term regulation of food intake

A

i) adipose cells secrete leptin (especially at night)
–leptin inhibits hunger pathways and stimulates satiety pathways

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65
Q

other factors that make impact food intake

A

temperature, stress, infection, the microbiome (community of bacteria that lives in the gut)

66
Q

Kidney Functions (5)

A

-filter blood, remove wastes, maintain blood volume (recall long term BP control), EPO secretion for red blood cell count control, maintain electrolyte levels

67
Q

Kidney Location

A

-retroperitoneal
-lumbar region

68
Q

kidney surface structures

coverings (3), where does hilum face, glands

A

-Coverings: renal capsule, adipose capsule, renal fascia

-adrenal glands sit on top of kidney

-hilum (indentation) faces medially

69
Q

Kidney internal structures (5)

A

-Cortex: outside (under capsule) light color

-medulla (middle): has darkly colored pyramid and lighter renal columns

-lobes: about 9 per kidney, each one is one pyramid and its associated cortex

-calyces: drain pyramids:
—minor calyx for one pyramid
—major calyx drains multiple pyramids

-renal pelvis: funnel a hilum

70
Q

Kidney internal structures

Renal pelvis

A

-renal pelvis: funnel at hilum

71
Q

Kidney internal structures

calyces

A

-calyces: drain pyramids:
—minor calyx for one pyramid
—major calyx drains multiple pyramids

72
Q

Kidney internal structures

lobes

quanitity+what does a lobe consist of

A

-lobes: about 9 per kidney, each one is one pyramid and its associated cortex

73
Q

Kidney internal structures

Medulla

A

-medulla (middle): has darkly colored pyramid and lighter renal columns

74
Q

Kidney internal structures

Cortex

A

(under capsule) light color

75
Q

Blood vessel Mapping

A
76
Q

Nephron and conducting duct

order (5)

A

a) glomerular capsule (bowman’s)
b) proximal convoluted tubule (PCT)
c) nephron loop (henle)
d) distal convoluted tubule (DCT)
e) collecting duct

77
Q

Nephron and conducting duct

a) glomerular capsule (bowman’s)

A

a) glomerular capsule (bowman’s)

Where filtration occurs: fluid moves from glomerular capillary to glomerular capsule

78
Q

Nephron and conducting duct

b) proximal convoluted tubule (PCT)

A

b) proximal convoluted tubule (PCT)

both reabsorption and secretion occur here

79
Q

Nephron and conducting duct

c) nephron loop (henle)

A

c) nephron loop (henle)

-descending limb- H2O reabsorbed
-accesending limb- Na+ reabsorbed

80
Q

Nephron and conducting duct

d) distal convoluted tubule (DCT)

A

-some reabsorption and secretion occurs

81
Q

Nephron and conducting duct

e) collecting duct

A

-collects some filtrate from multiple nephrons
-some reabsorption+ secretion

82
Q

Kidney Physiology

Three procesess

A

Filtration, Absorption, Secretion

83
Q

Step 1: Glomerular Filtration

Glomerular Filtration is a __,___ process in which__

A

Glomerular Filtration is a passive, nonselective process in which hydrostatic pressure of blood pushes fluid through filtration membrane

84
Q

Step 1: Glomerular Filtration

The Net Filtration Pressure (NFP) responsible for filtrate formation is given by the balance of

A

HP-OP (hydrostatic pressure and osmotic pressure)

NFP= Glomerulur HP (BP)- Capsular HP (Filtrate P)- Osmotic P (solute concentration in plasma)

85
Q

Step 1: Glomerular Filtration

The Glomerular Filtration Rate (GFR) is

A

around 20mL/min

-amount of filtrate formed in capsule in one minute

86
Q

Step 1: Glomerular Filtration

Maintenance of a relatively constant GFR is important because

A

reabsorption of solutes and water depend on how quickly filtrate flows through tubules

87
Q

Step 1: Glomerular Filtration

GFR depends (directly) on

A

1) permeability of glomerular membrane
2) size of glomerular membrane
3) NFP: net filtration pressure

88
Q

Step 1: Glomerular Filtration

GFR Is held constant through multiple mechanisms
a)renal autoregulation

A

i) myogenic mechanism- afferent arterioles respond to changes in pressure-> they dilate or constrict to compensate

ii) tubuloglobmerlur mechanism: change in local messenger levels (vasoactive chemicals) acting on afferent arterioles in response to flow (speed and saltiness) in nephron

89
Q

a)renal autoregulation

i) myogenic mechanism

A

i) myogenic mechanism- afferent arterioles respond to changes in pressure-> they dilate or constrict to compensate

90
Q

a)renal autoregulation

tubuloglobmerlur mechanism

A

ii) tubuloglobmerlur mechanism: change in local messenger levels (vasoactive chemicals) acting on afferent arterioles in response to flow (speed and saltiness) in nephron

91
Q

Step 1: Glomerular Filtration

GFR Is held constant through multiple mechanisms

b) Extrinsic Neural Mechanisms are stress-induced sympathetic responses that inhibit filtrate formation by

A

constricting afferent arterioles thus lowering NFP thus lowering GFR

92
Q

Step 1: Glomerular Filtration

GFR Is held constant through multiple mechanisms

c) the renin-angiotestin mechanism

A

-kidney reacts to Low BP by secreting renin

-renin triggers a cascade that helps raise blood volume+ systemic vasoconstriction so that BP rises and thus GFR raises to normal

93
Q

Step 2: Tubular Reabsorption

Tubular Reabsorption

occurs where (2 places )
retains what

A

-occurs both paracellularly and transcellularly

-retains viable nutrients, needed H20, and some electrolytes

94
Q

Step 2: Tubular Reabsorption

The most abundent cation of the filtrate is __ and resabsorption is usually active

where is the Na+ K+ pump

A

SODIUM

-Na+/K+ pump on basolateral membrane of tubual walls

95
Q

Step 2: Tubular Reabsorption

Obligatory Water Reabsorption occurs in the___where

A

In P.C.T. water returns to bloodstream by osmosis

96
Q

Step 2: Tubular Reabsorption

Secondary active transport is responsible for absorption of

A

glucose, amino acids, most cations, and occurs when solutes are co transported with Na+

a) the Na+ in the cotransporter is moving down its concentration gradient

97
Q

Step 2: Tubular Reabsorption

different areas of the tubules have different

A

absorpative capabilities

98
Q

Step 3: Tubular secretion

Tubular secretion disposes of

A

unwanted solutes

-excess H+, K+, sometimes drugs

99
Q

Step 3: Tubular secretion

Tubular Secretion Is most active in

A

PCT but is also in other parts of the tubule

100
Q

Regulation of Urine Concentration and volume

one of the critical kidney functions is to keep the solute load of body fluids by

A

by regulating urine concentration and volume

300m 0sm

101
Q

Regulation of Urine Concentration and volume

The countercurrent mechanism involves interaction between

A

between filtrate through the limb of nephron loops (henle)

102
Q

what is freely absorbed by the descending limb of the loop of henle

A

water

103
Q

since water is freely absorbed by the descending limb of the loop of henle FILTRATE CONCENTRATION ___and water is ___

A

FILTRATE CONCENTRATION increases and water is reabsorbed

104
Q

the ascending limb is permeable to ___ but not to ___

A

the ascending limb is permeable to solutes but not to H2O

105
Q

In the collecting duct, urea diffuses into the ___, contributing to

A

diffuses into the deep medullary tissue, contributing to the increasing osmotic gradient ecountered by the filtrate as it moves through the loop

106
Q

Production of a dilute urine occurs when

A

-overhydrated SO

-decreased ADH secretion
-the collecting duct carries dilute urine towards minor calyx w/o much reabsorption of H2O

107
Q

formation of concentrated urine occurs when

A

-when under-hyrdrated
-the pituitary secretes more ADH causing insertion of more aquaporins into walls of conducting duct
-this is falutative H2O reabsorption

108
Q

Diuretics act to

A

a) inhibiting Na+ reabsorption, thus less H2O reabsorption

b) decreased ADH will increase urine output (eg. alcohol, diabetes insipidus)

c) if other solutes are in urine (e.g. diabetes militus: lots of glucose in filtrate)

109
Q

Renal Clearance

Clearance refers to the volume

A

volume of plasma that is cleared of a specific substance in a given period of time mL/min

110
Q

Renal Clearance

Inulin is a useful plant polysaccharide (to measure GFR) for this because inulin

renal clearence equation

A

-inulin is filtered but not reabsorbed nor secreted (mg/mL)

R.C.=u*v/ p

u=conc of test substance in urine
v= urine output over time mL/min
p= plasma conc of test substance (mg/mL)

111
Q

if the clearance value is greater than the inulin clearance rate, then

A

substance is secreted

112
Q

Ureters (2)

location, length

wall

A

-retroperitoneal, 1 ft long
-from kidney to bladder

WALL
-mucosa: transitional epithelium+lamina propria

-smooth m of muscularis

-adventitia: connective tissue

113
Q

urinary bladder

location, 2 things it consists of

wall

A

-retroperitoneal, behind pubic symphysis

-rugae: folds

-trigone: region of bladder floor, opening of two ureters+ 1 urethra

WALL
-mucosa: transitional epithelium

-smooth m= detrusor m.

-adventitia: connective tissue

114
Q

urethra

from where to where

lining (3)

A

-tube from bladder to outside body

-its lining: transitional epithelium->pseudostratified-> stratified squamous

115
Q

Micturation or urination is the act of

A

emptying the bladder

116
Q

voluntary initiation of voiding reflexes results in the activation of the micturation centers of the __ which signals the ___neurons that stimulates contration of the __ and relaxation of___

-what are the things at the bottom of the bladder

-what does the somatic nervous system need to do

A

voluntary initiation of voiding reflexes results in the activation of the micturation centers of the PONS which signals the PARASYMP neurons that stimulates contration of the DETRUSER M. and relaxation of the URINARY SPHINCTER

-internal urethral spincters of smooth m. (at bottom of bladder)

-somatic nervous system needs to relax the skeletal m. of the external urethral sphincter

117
Q

Body water content

Total body water muscle vs fat

A

Fat only- 20% of water
Muscle- 75% of water

118
Q

Body water content

Age

A

Infants- 75% H2O
Older adults- 50% H2O

119
Q

Body water content

Gender

A

Male - 60% H2O
Female- 50% H2O

120
Q

Fluid Compartments

two main fluid compartments inbody

A

2/3 of H2O is intracellular
1/3 of H2O is exracellular

121
Q

Fluid Compartments

there are two subcompartments of the extracellular fluid

A

80% of extracellular fluid is interstitial
20% contains blood plasma

122
Q

Composition of bodily fluids

nonelectrolytes include most

A

most organic moleules, do not dissociate in water, and carry no electrical charge (e.g. glucose)

123
Q

Composition of bodily fluids

Electrolytes are

A

-are more numerous but less massive
-dissociate into ions in water
-include: salts, acids, and bases
-important contributers to osmotic pressure
–1m NaCl is a 20sm solution
-important ions include: Na+, K+, Cl-,Ca+

124
Q

For proper hydration, water intake must equal

WATER INTAKE

A

water output

water intake: food+water that has been ingested, cellullar metabolism (condensation rxns)

125
Q

Water Output

insensible losses include

A

-urine, feces, sweat
-insensible losses: breathing, osmosis through skin

126
Q

the thirst mechanism is controlled by

what contributes to feelings of thirst

A

the hypothalamic thirst center

a) osmoreceptors detect high Osm of plasma

b) low BP, dry mouth, high levels of angiotestin 2, empty stomach can all contribute to feelings of thirst

127
Q

regulation of water output

obligatory water loss

A

-mainly controlled by ADH (which limits output)

-but some water loss in urine is obligatory, as is loss of water vapor in breath

128
Q

the amount of water reabsorbed in the renal collecting ducts is proportional to

A

ADH release

129
Q

Influence of ADH

When ADH levels are low, most water in the collecting ducts..

A

is not reabsorbed, leading to high quantities of dilute urine

130
Q

Influence of ADH

When ADH levels are high, filtered water is

A

reabsorbed, resulting in a lower volume of concentrated urine

131
Q

ADH secretion is promoted or inhibited by the ____ in response to (3 things)

A

the hypothalamus in response to changes in solute concentrartion of extracellular fluid, large changes in blood pressure or volume, or vasular baroreceptors

132
Q

Dehydration occurs when

A

water out> water in

-cells shrink
-weight loss, confusion, shock

133
Q

Hypotonic hydration results from

A
  • decreased Osm of ECF
    -cells swell
    -water intoxication, hyponatremia, renal insufficiency
134
Q

edema is the accumulation of fluid in the

possible causes

A

extracellular space

a) high capillary BP (e.g. in heart failure)
b) hyponatermia- thus low osmotic p
c) lymphatic impairment- extreme example is filariasis (“elaphentitis”)

135
Q

The central role of sodium in fluid and electrolyte balance

A

important to regulation due to its abundence in osmotic pressure

136
Q

Regulation of sodium balance

when aldosterone secretion is high, nearly all filtered sodium

A

nearly all filtered sodium is reasbsorbed in the distal convoluted tubule in and the collecting duct

increased aldosterone= increased sodium reabsorption

137
Q

the most important trigger for the release of aldosterone is the

response to 3 things

A

renin-angiotestin mechanism, initiated in response to sympathetic stimulation, decrease in filtrate osmolarity, or decreased blood pressure

138
Q

cardiovascular baroreceptors monitor

A

blood volume so that blood pressure remains stable

139
Q

Atrial Natriuretic Peptide reduces blood pressure and blood volume by

A

inhibiting release of renin, aldosterone, ADH and stimulating vasodialation

140
Q

Estrogens are chemically similar to aldeosterone and enhance

A

reabsorption of Na+ in kidney

141
Q

Glucocorticoids such as cortisol___Na+ reabsoprtion

A

increase

142
Q

potassium is crucial to the maintenence of

A

the membrane potential of neurons and muscle cells,

and is a buffer that compensates for shifts of hydrogen ions in or out of cells

both hypo and hyperkalemia can cause irregular heart rhythm

143
Q

Aldosterone influences K+ pump secretion as

A

it adds Na+/K+ pumps to kidney tubules thereby increasing K+ secretion

144
Q

Because of the abundence of hydrogen bonds in the body’s functional proteins, they are strongly influenced by

A

hydrogen ion concentration

145
Q

When arterial blood pH rises above 7.45 it is

A

Alkalosis

146
Q

When arterial blood pH drops below 7.35 it is

A

acidosis

147
Q

Most hydrogen ions originate as

A

metabolic byproducts of CO2 or breakdown of fats

148
Q

A chemical buffer is a

A

set of molecules suh as weak acid-weak base pair that resists change of pH

149
Q

The bicarbonate buffer system is the main buffer of

A

extracellular fluid and consists of a carbonic acid and its salt, sodium bicarbonate

150
Q

The bicarbonate buffer system

when a strong acid is added to the solution

A

bicarbonic ions bind much of the H+ that came off the strong acid

151
Q

The bicarbonate buffer system

when a strong base is added to the solution

A

-carbonic acid donates more H+ to bing the OH- of the strong base

152
Q

the protein buffer system

A

is main system inside cells

-proteins are amphoteric-can be weak acids or bases

-COOH (carboxyl) groups can donate H+, NH3 groups (amine) can accept H+

153
Q

When hypercapnia occurs, pH drops, activating respiratory centers, resulting in

A

increased ventilation to blow off more CO2 (returning pH up to normal)

154
Q

When pH rises, the respiratoru centers are depressed, allowing

A

CO2 to accumulate in the blood, lowering pH to normal

155
Q

Renal mechanisms of acid-base balance

bicarbonate ions can be converted from filtrate or synthesized by

A

Type A intercalated cells in response to acidosis

156
Q

Renal mechanisms of acid-base balance

when the body is in alkalosis,

A

type B intercallated cells excrete bicarbonate, and reclaim hydrogen ions

157
Q

Abnormalities of acid-base balance

respiratory acidosis is characterized by

A

a rise in CO2 that lowers blood pH

-often caused by brreathing disorders

158
Q

Abnormalities of acid-base balance

respiratory alkalosis is characterized by

A

low CO2 that causes pH to rise= hyperventilations

-often caused by anxiety or being at altitude

159
Q

Metabolic acidosis is characterized by

A

any drop in blood pH not caused by a breathing problem e.g. diarrhea

160
Q

metabolic alkalosis is indicated by

A

any rise in blood pH not due to breathing

e.g. constipation or vomiting

161
Q

Abnormalities of acid-base balance

Compensations

A

to deal with pH disturbances, physiologically the kidneys adjust H+ anhd HCO3- (BICARB) secretion+ reabsorption while respiratory system adjusts breathing depth and rhythm