Chapter 25 Flashcards
1
Q
catabolism vs anabolism
A
exergonic, break down complex organic molecules into simpler ones, decomposition reactions vs endergonic, build bigger molecules from simpler ones, synthesis reactions
2
Q
ATP consists of
A
adenine molecule, a ribose molecule, and three phosphate groups bonded to
one another
3
Q
ATP in anabolism and catabolism
A
anabolism: transfer energy from
ATP to complex molecules
catabolism: transfer energy from
complex molecules to ATP
4
Q
oxidation
A
removal of electrons=decrease in potential energy of atom/molecule
5
Q
dehydrogenation reactions
A
common biological oxidation reaction where hydrogen is removed
6
Q
reduction
A
addition of electrons=increase in potential energy of atom/molecule
7
Q
Two coenzymes that are commonly used by animal cells to carry hydrogen atoms
A
nicotinamide adenine dinucleotide
(NAD): a derivative of the B vitamin niacin
flavin adenine dinucleotide (FAD), a derivative of vitamin B2 (riboflavin).
8
Q
phosphorylation
A
addition of phosphate group to a molecule
9
Q
3 ways organism use phosphorylation to generate ATP
A
Substrate-level phosphorylation
Oxidative phosphorylation
Photophosphorylation
10
Q
Substrate-level phosphorylation
A
transferring high energy phosphate group from substrate directly to ADP
occurs in cytosol
(ADP/GDP phosphorylated to produce ATP/GTP)
11
Q
Oxidative phosphorylation
A
removes electrons from organic compounds and passes them through the electron transport chain, to O2
occurs in inner mitochondrial membrane
(ADP to ATP using free energy produce from reactions of ETC)
12
Q
Photophosphorylation
A
occurs only in chlorophyll-containing
plant cells or in certain bacteria containing light absorbing pigments
13
Q
glucose use in the body (4)
A
ATP production
AA Synthesis
Glycogen synthesis
Triglyceride synthesis
14
Q
glycogenesis vs lipogenesis
A
glucose monomers are combined
to form the polysaccharide glycogen by hepatocytes and muscle fibers
vs
synthesis of triglycerides
15
Q
high level of insulin increases ___ ________ __ _____ into the plasma membranes of most body cells, thereby increasing ___ ____ __ ___________ _________ of _______ into cells.
A
the insertion of GluT4 (glucose transporter)
the rate of facilitated diffusion
glucose
16
Q
In neurons and hepatocytes, another type of GluT is always present in the ______ ________ , so glucose entry is always “______ __ .” On entering a cell,
glucose becomes _____________. Because GluT cannot transport
_____________ _______, this reaction traps glucose within the cell.
A
plasma membrane
turned on
phosphorylated
phosphorylated glucose
17
Q
cellular respiration (what/set of reactions)
A
oxidation of glucose to produce ATP
four sets of reactions: glycolysis, the
formation of acetyl coenzyme A, the Krebs cycle, and the electron transport chain
18
Q
glycolisis (step of cellular respiration/what/produce)
A
1
A set of reactions in which one 6-carbon molecule of glucose is oxidized and split into two 3-carbon molecules of pyruvic acid is produced. The reactions also produce 4 molecules of ATP and uses 2 = two total, and two energy-containing NADH plus H+
19
Q
Formation of acetyl coenzyme A (step of cellular respiration/what/produce)
A
2
A transition step that prepares
pyruvic acid for entrance into the Krebs cycle. This step also produces energy-containing NADH + H+ plus carbon dioxide
(CO2)
20
Q
Krebs cycle reactions (step of cellular respiration/what/produce)
A
3
These reactions oxidize acetyl coenzyme A and produce CO2, ATP, NADH + H+, and FADH2.
21
Q
Electron transport chain reactions (step of cellular respiration/what/produce)
A
4
These reactions oxidize NADH plus H+ and FADH2 and transfer their electrons through a series of electron carriers
22
Q
aerobic respiration vs anaerobic glycolysis
A
Krebs cycle and electron transport chain require oxygen and are collectively known as aerobic respiration
vs
glycolysis occurs by itself under anaerobic conditions, it is referred to as anaerobic glycolysis
23
Q
which step of cellular respiration can occur under anaerobic conditions
A
glycolysis
24
Q
Fate of Pyruvic acid (2 ways)
A
Anaerobic: plus 2 hydrogen ions= lactic acid -> hepatocytes convert back to P acid
Aerobic: convert to acetylene coenzyme A -> links glycolysis (in cytosol) and KREBs (in mitochondria)
25
What cell can only produce ATP from glycolysis and why
RBC as they don’t have mitochondria=no Krebs
26
What happens to Pyruvic acid when it loses a molecule of carbon dioxide and what does it release
It become an acetyl group
First reaction in cellular respiration to release CO2
27
Decarboxylation def
Removal of CO2 by a substance
28
Acetyle coenzyme A is made up of
Acetyl group plus coenzyme A
29
Krebs cycle AKA and why
Citric acid cycle as it is the first molecule formed when acetyl group joins the cycle
30
Where do Krebs reactions occur
Matrix of mitochondria
31
What is the final electron acceptor of the electron transport chain
Oxygen
32
How many acetyl CoA produced by one glucose and importance
2 = 2 spins of Krebs cycle
33
Why is the electron transport chains mechanism of producing ATP called chemiosmosis
Because it links reactions (passage of electrons down transport chain) with the pumping of hydrogen ions
34
Why is the electron transport chains mechanism of producing ATP called chemiosmosis
Because it links reactions (passage of electrons down transport chain) with the pumping of hydrogen ions
35
What are the electron carriers (5) and description
Flavin mononucleotide (FMN): flavoprotein derived from riboflavin
Cytochromes: proteins with an iron containing heme
Iron-sulfur (Fe-S) centers: 2 or 4 atoms iron bound to sulfur atoms
Copper (Cu) atoms: bound to 2 proteins in the chain
Coenzyme Q (Q): nonprotein, low molecular weight carrier mobile in lipid bilayer
36
Oxidation of one glucose molecule to two Pyruvic acid molecules (what step in cellular respiration and produces)
Glycolysis
2 ATP by substrate level phosphorylation
37
Production of 2 NADH plus H+ during glycolysis produces
3 or 5 ATP by oxidative phosphorylation
38
The formation of 2 molecules of acetyl CoA produce
5 ATP by oxidative phosphorylation
39
The oxidation of succinyl-CoA to succinic acid (what step of cellular respiration/produces)
Krebs/ETC
2 GTP that are converted to 2 ATP by substrate level phosphorylation
40
Production of 6 NADH plus 6 H+ (where in cellular respiration/produce)
Krebs/ETC
15 ATP by oxidative phosphorylation
41
Production of 2 FADH2 (where in cellular respiration/produce)
Krebs/ETC
3 ATP oxidative phosphorylation
42
What does cellular respiration produce total (ATP, # O2/CO2 used or produced)
30-32 ATP per glucose molecule
6 O2 used and 6 CO2 produced
43
Glycogenesis vs glycogenolysis vs gluconeogenesis vs glycolysis
Insulin stimulates hepatocytes/skeletal muscle cells to produce gylcogen
Vs
Stored glycogen broken down into glucose when needed
Vs
Process where glucose is formed by other non carbohydrate sources stimulated by cortisol/glucagon
Vs
Convert glucose to Pyruvic acid (first step in cellular respiration)
44
Gluconeogenesis
Uses lactic acid, glycerol and certain AA to produce glucose
Stimulated by cortisol (adrenal cortex
45
What percentage of energy release in catabolism is used for cellular function/what is the rest used for
About 40% of the energy released in catabolism is used for cellular functions; the rest is converted to heat
46
are lipids (mostly triglycerides) nonpolar or polar and what does that make them hydrophilic or hydrophobic
non polar, hydrophobic
47
what are lipoproteins and whats the function
lipids combined with proteins produced by liver/intestine to make lipids hydrophilic
phospholipids, cholesterol, and proteins surround the inner lipids
48
apoproteins (where, designated by, function)
proteins in outer shell of lipoprotein designated by the letters A, B, C, D, and E plus a number
help solubilize the lipoprotein in body fluids, and each apoprotein has specific functions
49
chylomicrons (size/weight/form where/transport/contain/what apoproteins release what/rest taken up by/docking protein)
largest/lightest lipoproteins
form in mucosal epithelial cells of SI
transport dietary (ingested) lipids to adipose tissue for storage
1–2% proteins, 85% triglycerides, 7% phospholipids, and 6–7% cholesterol, plus a small amount of fat soluble vitamins
apo C-2, activates endothelial lipoprotein lipase=removes fatty acids->taken up by adipocytes/muscle cells
Hepatocytes remove chylomicron remnants from the blood via receptor-mediated
endocytosis
apo E, is the
docking protein
50
Very-low-density lipoproteins (VLDLs) (formed where, transport what, contain, apoproteins release what, turn into what+when)
form in hepatocytes
contain about 10% proteins, 50% triglycerides, 20% phospholipids,
and 20% cholesterol.
mainly endogenous (made in the body) lipids
transport triglycerides synthesized in
hepatocytes to adipocytes for storage
lose
triglycerides as their apo C-2 activates endothelial lipoprotein lipase,
and the resulting fatty acids are taken up by adipocytes for storage
and by muscle cells for ATP production. As they deposit some of their
triglycerides in adipose cells, VLDLs are converted to LDLs.
51
low density lipoproteins (contain, transport, docking protein, excess, AKA)
contain 25% proteins, 5%
triglycerides, 20% phospholipids, and 50% cholesterol.
They carry about 75% of the total cholesterol in blood and deliver it to cells throughout the body for use in repair of cell membranes and synthesis
of steroid hormones and bile salts
docking protein: apo B100
in excess=deposit cholesterol around SM fibers in arteries=fatty plaques=bad cholesterol
52
high density lipoproteins (contain, function, AKA)
contain 40–45% proteins, 5–10% triglycerides, 30% phospholipids, and 20% cholesterol
remove excess cholesterol from body cells/blood and transport it to the liver for elimination
prevent fatty plaques=AKA good cholesterol
53
2 sources of cholesterol
food, most produced by hepatocytes
54
how can fatty foods that don’t contain any cholesterol at all still dramatically increase blood cholesterol level in two ways
high intake of dietary fats stimulates reabsorption of cholesterol-containing bile back into the blood=cholesterol is lost in the feces
when saturated fats are broken down in the body, hepatocytes use some of the breakdown products to make cholesterol
55
lipid profile test/how to calculate LDL/normal TC, LDL-C, HDL-C, Trigylcerides
measures total cholesterol (TC), HDL cholesterol, and triglycerides (VLDLs)
LDL-cholesterol = TC − HDLcholesterol − (triglycerides/5).
TC under 200 mg/dL,
LDL-cholesterol under 130 mg/dL
HDL-cholesterol over 40 mg/dLN
triglycerides range of 10–190 mg/dL
56
Triglycerides stored in adipose
tissue constitute ___ of all body energy reserves
98 percent
57
triglycerides are stored ____ _______ than glycogen, in part because triglycerides are ___________ and do not exert _______ ________ on ____ _________
more readily
hydrophobic
osmotic pressure
cell membranes
58
Adipocytes in the subcutaneous layer contain about ___ of the stored
triglycerides. Other adipose tissues account for the other ____: about
___ around the kidneys, ___ in the omenta, ___ in genital areas,
___ between muscles, and ___ behind the eyes, in the sulci of the
heart, and attached to the outside of the large intestine.
50%
half
12%
10-15%
15%
5-8%
5%
59
Triglycerides in adipose tissue are continually broken down and _________.
Thus, the triglycerides stored in adipose tissue today are not the same
molecules that were present ____ _____ because they are continually
released from storage, transported in the _____, and redeposited in
other adipose tissue cells
resynthesized
last month
blood
60
Epinephrine and norepinephrine _____ triglyceride breakdown into ____ ____
and _______. These hormones are released when sympathetic tone
________.
enhance
fatty acids
glycerol
increases
61
other lypolytic hormones include _____, ______ hormones, and ______ like growth factors. By contrast, ______ inhibits lipolysis.
cortisol
thyroid
insulin
insulin
62
Glycerol is converted by many cells of the body to ___________, one of the compounds also formed during the catabolism of glucose. If ATP supply in a cell is ____ , glyceraldehyde 3-phosphate is converted into ______, an example of gluconeogenesis. If ATP supply in a cell is ____, glyceraldehyde 3-phosphate enters the catabolic pathway to ______ ____
glyceraldehyde 3-phosphate
high
glucose
low
pyruvic acid
63
Fatty acids are catabolized differently than glycerol and yield
____ ATP
more
64
beta oxidation (what/where)
first stage in fatty acid metabolism, occurs in matrix of mitochondria
65
Beta Oxidation
Enzymes remove ___ ______ _____ at a time from the long chain of carbon atoms composing a fatty acid and attach the resulting ____-____ ______ to ________, forming acetyl CoA. Then, acetyl CoA enters the ____ ____. A __-_____ fatty acid such as palmitic acid can yield as many as ___ ATPs on its complete oxidation via beta oxidation, the Krebs cycle, and the electron transport chain.
2 carbon atoms
2 carbon fragment
coenzyme A
Krebs cycle
16-carbon
129
66
acetoacetic acid
2 acetyl CoA molecules condensed by hepatocytes
67
Some acetoacetic acid is converted
into ______-_______ acid and _____
beta-hydroxybutyric
acetone
68
ketone bodies and ketogenesis (occurs)
beta-hydroxybutyric, acetone, and acetoacetic acid collectively known as ketone bodies
formation of ketone bodies=ketogenesis
occurs in hepatocytes
69
____ cells and ____ cells can synthesize lipids from ______ or ____ ____ through lipogenesis, which is stimulated by _____
Liver
adipose
glucose
amino acids
insulin
70
Lipogenesis occurs when individuals consume ______ calories than
are needed to satisfy their ___ needs. Excess dietary ______, ______, and ___ all have the same fate—they are converted into _______.
more
ATP
carbohydrates
proteins
fats
triglycerides
71
Certain amino acids can undergo the following reactions: amino acids → ____ ____ → _____ _____ → triglycerides.
The use of glucose to form lipids takes place via two pathways:
(1) glucose → __________ __-_______ → glycerol
(2) glucose → _________ __-_____→ _____ ____→ fatty acids.
The resulting glycerol and fatty acids can undergo _______ reactions to become _____ triglycerides, or they can go through a series of ________ reactions to produce other _____ such as __________, _________, and __________.
acetyl CoA
fatty acids
glyceraldehyde 3-phosphate
glyceraldehyde 3-phosphate
acetyl CoA
anabolic
stored
anabolic
lipids
lipoproteins
phospholipids
cholesterol
72
are proteins or carbohydrates/lipids stored once broken down
carb/lipid=stored
protein=not
73
what are proteins broken down to/function
amino acids
oxidized to produce ATP or to synthesize new proteins for body growth and repair
74
what happens to excess amino acids
converted into glucose (gluconeogenesis) or triglycerides (lipogenesis)
75
The active transport of amino acids into body cells is stimulated by
______-____ ______ _______ and _______. Almost immediately aft er
digestion, amino acids are reassembled into _______. Many proteins function as _______; others are involved in transportation (_______) or serve as _________, clotting chemicals (_______), hormones (_______), or contractile elements in muscle fibers (_____ and ______). Several proteins serve as ________ _________ of the body (collagen, elastin, and keratin).
insulin-like growth factors (IGFs)
insulin
proteins
enzymes
hemoglobin
antibodies
fibrinogen
insulin
actin
myosin
structural components
76
what is protein catabolism manly stimulated by
cortisol from adrenal cortex
77
before amino acids can be oxidized, what has to happen first
first be converted to molecules that are part of the Krebs cycle or can enter the Krebs cycle, such as acetyl CoA
their amino group (NH2)
must first be removed—a process called deamination
78
deamination (what,where,produces)
removal of amino group
occurs in hepatocytes
produces ammonia->liver cells con vert to urea
79
where is protein anabolism carried out
on ribosomes of almost every cell
80
essential amino acids (how many, why they are essential, can/cant be synthesized)
10
must be present in the diet because they cannot be synthesized in the body in adequate amounts
cannot synthezie=isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine
can synthesize (inadequate amounts)=arginine and histidine
81
complete protein (what/ex.)
contains suff icient amounts of all essential amino acids. Beef, fish, poultry, eggs, and milk
82
incomplete protein (what/ex.)
does not contain all essential amino acids. Examples of incomplete proteins are leafy green vegetables, legumes, and grains
83
nonessential amino acids
can be synthesised adequately by body
84
transamination
the transfer of an amino group from
an amino acid to pyruvic acid or to an acid in the Krebs cycle. Once the
appropriate essential and nonessential amino acids are present in cells, protein synthesis occurs rapidly
(how nonessential amino acids are synthesized on body)
85
3 key molecules (why are they called that)
glucose 6-phosphate, pyruvic acid, and acetyl coenzyme A
play pivotal role in metabolism
86
role of glucose 6-phosphate (4) (plus some description for each)
synthesis of glycogen: occurs when glucose is abundant, occurs in SMF/hepatocytes
release of glucose into the bloodstream: dephosphorylated to glucose
synthesis of nucleic acids: precursor to ribose 5-phosphate=needed for nucleic acid
glycolysis: anaerobically -> pyruvic acid+ATP
87
role of pyruvic acid (3) (plus some description of each)
production of lactic acid: no oxygen=lactic acid->into bloodstream-> taken up by hepatocytes=turn back into pyruvic
production of alanine: transamination= amino group (–NH2)+pyruvic acid=amino acid alanine, or be removed from alanine=pyruvic acid
gluconeogenesis: converted to oxaloacetic acid=form glucose 6-phosphate
88
Role of acetyl coenzyme A (2) (plus some description of each)
entry into the krebs cycle: vehicle for 2-carbon acetyl groups
synthesis of lipids: synthesis of
certain lipids, including fatty acids, ketone bodies, and cholesterol
89
absorptive vs postabsorptive state
ingested nutrients are entering the bloodstream, and glucose is readily available for ATP production vs absorption of nutrients from the GI tract is complete, and energy needs must be met by fuels already in the body
90
how long does a typical meal need to absorb for
4 hours
91
absorptive state reactions (7)
1. catabolism of glucose: 50% gluc=catabolized (cellular resp) for ATP
2. catabolism of AA: enter hepatocytes=deaminated=ketone acids-> Krebs for ATP or synthesize glucose/fatty acids
3. synthesis of proteins: many AA do this
4. catabolism of a few dietary lipids: small # for energy, rest stored in adipose
5. glycogenesis: taken up by liver/SM=converted to glycogen
6. lipogenesis: liver converts to fatty acids=synthesis of triglycerides (40%), adipose cells convert to storage triglycerides (10%)
7. transport of triglycerides from liver to adipose tissue: most fatty acids/triglycerides in liver packed into VLDLs (carry lipids to adipose tissue)
92
Soon after a meal, _______-_______ __________ ________ (___), plus the rising blood levels of ______ and certain ______ _____, stimulates pancreatic ____ cells to release the hormone insulin. In general, insulin _______ the activity of enzymes needed for anabolism and the synthesis of storage molecules; it _______ the activity of enzymes needed for catabolic or breakdown reactions. Insulin promotes the entry of ______ and _____ _____ into cells of many tissues, and it stimulates the conversion of glucose to _______(______) in both _____ and _____ cells. In liver and adipose tissue, insulin enhances the synthesis of _______ (_______), and in cells throughout the body, insulin stimulates _______ synthesis. ______ and the ______ hormones (T3 and T4) also stimulate protein synthesis.
glucose-dependent insulinotropic peptide (GIP)
glucose
amino acids
beta
increases
decreases
glucose
amino acids
glycogen (glycogenesis)
liver
muscle
triglycerides (lipogenesis)
protein
IGFs
thyroid
93
Glucose entry into most body cells occurs via _______ _______ (_____) molecules, a family of transporters that bring glucose into cells via ________ _______
glucose transporter (GLUT)
facilitated diffusion
94
A high level of _______ increases the insertion of one type of GLUT, called
______, into the plasma membranes of most body cells (especially muscle fiber and adipocytes), increasing the rate of facilitated diffusion of
glucose into cells. In _______ and _______, however, other types of
GLUTs are always present in the plasma membrane, so glucose entry is
always “turned on.” Upon entering a cell, glucose becomes ________. Because GLUT cannot transport ________ glucose, this
reaction traps glucose within the cell.
insulin
GLUT4
neurons
hepatocytes
phosphorylated x2
95
Hormonal Regulation of Metabolism in the Absorptive State (location/hormone)
1. Facilitated diffusion of glucose into cells
2. active transport of AA into cells
3. glycogenesis
4. protein synthesis
5. lipogenesis
1. most cells; insulin
2. most cells; insulin
3. hepatocytes/muscle fibers; insulin
4. all cells; insulin, IGFs, thyroid hormones
5. adipose cells/hepatocytes; insulin
96
the main metabolic challenge during the postabsorptive state is to maintain
the normal blood _____ level of ___-______
glucose
70-100 mg/100 mL
97
The reactions of the postabsorptive state that produce glucose (first 5)
1. glycogenolysis in liver: provide 4h supply of glucose=released into blood
2. glycogenolysis in muscle: glucose catabolized to provide ATP for muscle contraction
3. lipolysis: trig broken down to fatty/glycerol->into blood->into liver=glucose
4. protein catabolism: release AA=converted to glucose via liver
5. gluconeogenesis: from lactic acid, glycerol, or AA
98
the reactions of the postabsorptive state that don't use glucose (6-9)
6. catabolism of fatty acids: most
cells catabolize fatty acids directly-> into Krebs cycle as acetyl CoA=produce ATP through the ETC
7. catabolism of lactic acid: cardiac muscle produces ATP aerobically from this
8. Catabolism of AA: in hepatocytes, directly catabolized to ATP
9. Catabolism of ketone bodies: hepatocytes convert fatty->ketone bodies=used for ATP production
99
Both hormones and the _______ division of the _______ nervous system regulate metabolism during the postabsorptive state. The hormones that regulate postabsorptive
state metabolism sometimes are called ____-_____ hormones
because they counter the effects of _____ during the absorptive
state. As blood glucose level declines, the secretion of insulin ____ and
the release of anti-insulin hormones ____
sympathetic
autonomic
anti insulin
insulin
falls
rises
100
When blood glucose concentration starts to drop (post-absorptive state), the pancreatic ____ cells release the hormone _______. The primary target tissue of glucagon is the _____; the major effect is increased release of _____ into the bloodstream due to ____________ and __________.
alpha
glucagon
liver
glucose
gluconeogenesis
glycogenolysis
101
______ promotes gluconeogenesis, lipolysis, and protein catabolism
cortisol
102
Glucose-sensitive neurons in the __________ detect low blood glucose and increase _________ output. As a result, sympathetic nerve endings release the neurotransmitter ________, and the adrenal medullae release two catecholamine hormones,________ and ______, into the bloodstream. Like glucagon, epinephrine stimulates ______ breakdown. Epinephrine and
norepinephrine are both potent stimulators of ______. These actions
of the catecholamines help to increase glucose and free fatty acid
levels in the blood. As a result, muscle uses more ____ _____ for ATP
production, and more ______ is available to the nervous system
hypothalamus
sympathetic
norepinephrine
epinephrine
norepinephrine
glycogen
lipolysis
fatty acids
glucose
103
Hormonal regulation of metabolism in the post-absorptive state (location,hormones)
1. glycogenolysis
2. lypolysis
3. protein breakdown
4. gluconeogenesis
1. hepatocytes, SMF; glucagon, E
2. adipocytes; E/NE, cortisol, IGFs, thyroid hormones
3. most cells, esp. SMF; cortisol
4. hepatocytes, kidney cortex cells; glucagon, cortisol
104
fasting vs starving
fasting means going without food for many hours or a few days; starvation implies weeks or months of food deprivation or inadequate food intake
105
how long can you survive without food if you have water (why)
2m or more
Although glycogen stores are depleted within a few hours of beginning a fast,
catabolism of stored triglycerides and structural proteins can provide
energy for several weeks. The amount of adipose tissue the body contains determines the life span possible without food.
106
The most dramatic metabolic change that occurs with fasting and starvation is the increase in the formation of _____ _____ by hepatocytes
ketone bodies
107
energy balance
refers to the precise matching of energy intake (in food) to energy expenditure over time
108
calorie vs kilicalorie
amount of energy in the form of heat required to raise the temperature
of 1 gram of water 1°C
vs
1000 calories
109
enery content of:
carb
protein
fat
alcohol
4 kcal/g, 4, 9, 7
110
factors affecting metabolic rate (7)
hormones: thyroid hormones
exercise: increase 15x during exercise
NS: symp=increase BMR
body temp: higher temp=increase BMR
ingestion of food: increase BMR 10-20%
age: older=less
other: gender, climate, malnutrition
111
calorigenic effect
effect of thyroid hormones on BMR
112
food-induced thermogenesis
ingestion of food raises BMR due to energy costs of digestion
113
BMR number
1200-1800 and then extra 500-3000 for movement
114
3 things affecting total metabolic rate (TMR) and their percentages
BMR: 60%
physical activity: 30-35%
food-induced thermogenesis: 5-10%
115
A gain of 20 lb (9 kg) between ages 25 and 55 represents only a tiny
imbalance, about ____% more energy intake in food than energy expenditure
0.3
116
neuropeptide Y vs melanocortin vs grhelin
stimulate food intake when leptin/insulin levels are low
vs
inhibits food intake stimulated by leptin
vs
produced by stomach endocrine cells, increase appetite by stimulating neuropeptide Y
117
the bodies usual constant core temperature vs shell temp
37 C (98.6 F)
vs
1-6 C lower
118
core temp vs shell temp
in body structures deep to the skin and subcutaneous layer
vs
near the body surface—in the skin and subcutaneous layer
119
core temp too high vs too low causes death how
protein denaturation
vs
cardiac arrhythmias
120
conduction (what/body temp % lost)
heat exchange that occurs between molecules of two materials that are in direct contact with each other
3% body heat lost
121
convection (what/body temp % lost)
transfer of heat by the movement of air or water between areas of different temperatures
15% lost by air via convection and conduction
122
radiation (what/body temp % lost)
transfer of heat in the form of infrared rays between a warmer object and a cooler one without physical contact
in 21C room, 60% lost
123
evaporation (what/body temp % lost)
conversion of a liquid to a vapor
22% lost
124
The control center that functions as the body’s thermostat is a group
of neurons in the _______ part of the hypothalamus, the _____ ____. Neurons of the preoptic area generate action
potentials at a higher frequency when blood temperature _______
and at a lower frequency when blood temperature _______.
Action potentials from the preoptic area propagate to two other
parts of the hypothalamus known as the ___-_____ ____ and the
___-_____ _____
anterior
preoptic area
increases
decreases
heat-losing center
heat-promoting center
125
ways to increase the core temperature to the normal value (4)
1. vasoconstriction
2. release of E/NE: increase cellular metabolism=increase temp
3. shivering
4. release of thyroid hormones: increase metabolic rate=higher temp
126
6 main types of nutrients
water, carbohydrates, lipids, proteins, minerals, and vitamins
127
many experts recommend the following distribution of calories: ____ from carbohydrates, with less than ____ from simple sugars; less than ___ from fats (triglycerides are the main type of dietary fat), with no more than ___ as saturated fats; and about
___ from proteins
50-60%
15%
30%
10%
12-15%
128
minerals are
inorganic elements that occur naturally in the earth’s crust
129
Calcium and phosphorus form part of the matrix of ___. Because minerals do not form long-chain compounds, they are otherwise ___ building materials. A major role of minerals is to help regulate _______ reactions. Calcium, iron, magnesium, and manganese
are constituents of some ______. Magnesium also serves as a
catalyst for the conversion of ___ to ___. Minerals such as sodium and
phosphorus work in ______ ______, which help control the pH of body
fluids. Sodium also helps regulate the ______ of water and, along
with other ions, is involved in the generation of _____ ______
bone
poor
enzymatic
coenzymes
ADP
ATP
buffer systems
osmosis
nerve impulses
130
vitamins are and what is the function of most
Organic nutrients required in small amounts to maintain growth and
normal metabolism
Most vitamins with known functions are coenzymes
131
the body can assemble some vitamins if the raw materials, called _____, are provided
provitamins
132
fat vs water soluble vitamins
A,D,E,K; can be stored, ingested with other lipids
vs
B,C; can't be stored, dissolved in body fluids
133
In addition to their other functions, three vitamins—C, E, and
beta-carotene (a provitamin)—are termed _______ vitamins because they _____ oxygen free radicals. Free radicals damage ___ _____, ___, and other cellular structures and
contribute to the formation of artery-narrowing ________ _______ . Antioxidant vitamins are thought to play a role in protecting against some kinds of cancer, reducing the buildup of atherosclerotic plaque, delaying some effects of aging, and decreasing the chance of cataract formation in the lens of the eyes.
antioxidant
inactivate
cell membranes
DNA
atherosclerotic plaques
134
