lecture test #3 Flashcards

(236 cards)

1
Q

what are the 3 distinct internal regions of the kidney?

A

renal cortex, renal pelvis, and renal medulla

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2
Q

what is the renal cortex?

A

the superficial region of the kidney

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3
Q

what is the renal pelvis?

A

the region of the kidney that is continuous with the ureter. it is composed of minor calyces that collect urine from pyramidal papillae and minor calyces that collect urine from the minor calyces

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4
Q

what is the renal medulla?

A

the region of the kidney composed of medullary pyramids separated by renal columns. each pyramids and its surrounding cortical tissue is a lobe, with eight lobes in each kidney

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5
Q

what is the collecting duct of the nephron?

A

this structure is composed of simple squamous epithelium and has receptors of antidiuretic hormone (ADH). it drains the distal convoluted tubules

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6
Q

what is the glomerular (bowman’s) capsule of the nephron?

A

the site of filtrate formation. the hydrostatic pressure, also known as glomerular blood pressure, is the chief force pushing water and solutes across the filtration membrane

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7
Q

what is the distal convoluted tubule of the nephron?

A

the area of the nephron where reabsorption is hormonally regulated. this region contains microvilli, but isn’t the area of the majority of reabsorption

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8
Q

what is the glomerulus of the nephron?

A

a network of fenestrated capillaries that allow passage of some plasma elements into the glomerulus, but not large components like cells or proteins

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9
Q

what is the nephron loop?

A

the area of the nephron where its permeability determines the medullary osmotic gradient. it helps determine whether large amounts of dilute urine or small amounts of concentrated urine are formed. its thin segment aids in the passive movement of water out of the tubule. its descending limb contains fluid that becomes more concentrated as it descends and the ascending limb moves ions into interstitial space for reabsorption

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10
Q

what is the proximal convoluted tubule of the nephron?

A

the area where the majority of tubular reabsorption occurs. apical microvilli on the surface of its simple cuboidal epithelium increase surface area to increase absorption of filtrate components. these cells also have numerous mitochondria because of all the active transport occurring in region. low pressure, porous vessels reabsorb the solutes and water from this region of the nephron.

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11
Q

what are the major renal processes?

A

glomerular filtration, tubular reabsorption, and tubular secretion

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12
Q

what is tubular reabsorption?

A

reabsorption of useful substances, like water, glucose, amino acids, and electrolytes. they are transported out of the filtrate, into tubule cells and then enter capillary blood. while some of this reabsorption is passive, most of it is active. this process occurs primarily in the proximal convoluted tubule.

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13
Q

what is tubular secretion?

A

substances like hydrogen ions, potassium ions, creatinine and drugs are removed from peritubular capillary blood and secreted by tubule cells into the filtrate. this mechanism is very important for maintaining acid-base blood balance.

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14
Q

what is glomerular filtration?

A

water and solutes smaller than proteins are forced through capillary walls and the pores of the glomerular capsule into the renal tubule in a passive, non-selective process

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15
Q

what impact does antidiuretic hormone (ADH) have on urine or filtrate formation?

A

acts on the collecting duct by inserting aquaporins into the principle cells to make them more permeable to water, aiding in water reabsorption

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16
Q

what impact does atrial natriuretic peptide (ANP) have on urine or filtrate formation?

A

acts on the distal convoluted tubule and reduces blood sodium levels, therefore decreasing blood pressure

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17
Q

what effect does aldosterone have on urine or filtrate formation?

A

acts on the distal convoluted tubule and conserves sodium by aiding in sodium reabsorption. it reduces blood potassium concentration and is responsible for increasing blood pressure

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18
Q

what effect does parathyroid hormone (PTH) have on urine or filtrate formation?

A

acts on the distal convoluted tubule, where it aids in calcium reabsorption

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19
Q

urine is formed within the kidney. what are the structures from where urine is formed to where urine is eliminated from the body? (6 total)

A
  1. nephron
  2. collecting duct
  3. minor calyx
  4. major calyx
  5. ureter
    6.urethra
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20
Q

what is the function of the ureters?

A

carries urine from the kidneys to the bladder utilizing gravity and peristalsis

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21
Q

what is the function of the urethra?

A

transports urine out of the body

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22
Q

what is the function of the urinary bladder?

A

responsible for temporary urine storage, made possible in part by the transitional epithelium its composed of

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23
Q

what structure receives blood that has passed through the glomerulus?

A

efferent arteriole

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24
Q

what is the structural and functional unit of the kidney?

A

nephron

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25
each nephron is composed of what parts?
1. renal corpuscle - glomerulus - glomerular (bowman's) capsule 2. renal tubule - proximal convoluted tubule - nephron loop - distal convoluted tubule
26
what would result from vasodilation of the afferent arteriole? (4 total: glomerular filtration rate, net filtration, urine output, systemic blood pressure)
- increased glomerular filtration rate - increased net filtration - increased urine output - decreased systemic blood pressure
27
the glomerulus is composed of what type of capillaries?
fenestrated; allows some blood components to enter the glomerular capsule
28
what components are readily able to enter the glomerular capsule? (5)
- amino acids - water - inorganic ions (sodium, potassium, bicarbonate) - urea - glucose
29
what all is accomplished by the kidneys? (10 total)
1. excretion of drugs and toxins 2. gluconeogenesis 3. excretion of nitrogenous metabolic waste 4. vitamin D activation 5. maintains water balance of blood 6. production of erythropoietin (EPO) 7. long term acid-base balance regulation 8. production of renin 9. maintains the electrolyte balance of blood 10. regulation of ions within the ECF
30
what would normally be found in urine?
- ammonia - urea, uric acid, and creatinine, - bicarbonate ions - sodium and potassium
31
the renin-angiotensin-aldosterone mechanism is largely responsible for maintaining ______ ___________.
blood pressure
32
the sympathetic nervous system is activated when carotid sinus baroreceptors detect a decrease in _______ ___________.
blood pressure
33
what are effects of the renin-angiotensin-aldosterone mechanism as it attempts to raise blood pressure?
- vasoconstriction - aldosterone release, to increase sodium and water reabsorption - ADH release, to increase water reabsorption - stimulation of the hypothalamic thirst center
34
urine is composed of what remains of the filtrate formed within the nephron, but...
devoid of the water, nutrients and ions reabsorbed
35
is urine acidic or alkaline?
slightly acidic (pH~6)
36
how can we compare urine and blood plasma?
urine is similar to blood plasma, but lacks proteins
37
why is urine the color it is?
it is yellow due to the presence of urochrome, a product of hemoglobin destruction
38
true or false: the urinary bladder has an internal sphincter composed of smooth muscle
true
39
true or false: the kidney has an excretory organ, is supplied almost entirely by the parasympathetic ("rest and digest") branch of the nervous system
false: the kidney is entirely innervated by the sympathetic nervous system and does not receive any parasympathetic innervation
40
what organ or tissue produces aldosterone?
adrenal cortex
41
what organ or tissue produces atrial natriuretic peptide?
atria of the heart
42
what organ or tissue produces parathyroid hormone (PTH)?
parathyroid gland
43
what organ or tissue produces antidiuretic hormone (ADH)?
hypothalamus
44
what action does aldosterone have on their target tissues?
increases reabsorption of Na+ and h2o while causing excretion of K+, in the kidney tubules
45
what action does atrial natriuretic peptide (ANP) have on their target tissues?
decreases Na+ reabsorption and renin release in the kidneys and also inhibits the release of aldosterone by the adrenal cortex
46
what action does parathyroid hormone (PTH) have on their target tissues?
stimulates reabsorption of Ca2+ in the distal convoluted tubule stimulates osteoclasts to reabsorb bone matrix promotes vitamin D activation to increase absorption of Ca2+ by the intestinal mucosal cells
47
what action does antidiuretic hormone (ADH) have on their target tissues?
causes an increase in the # of aquaporins in the apical membranes of the principle cells of the collecting ducts to increase water reabsorption and produce more concentrated urine
48
what tissue or organ secretes atrial natriuretic peptide?
atria of the heart
49
what tissue or organ secretes aldosterone?
adrenal cortex
50
what tissue or organ secretes parathyroid hormone (PTH)?
parathyroid gland
51
what tissue or organ secretes antidiuretic hormone (ADH)?
posterior pituitary gland
52
what part of the nephron does atrial natriuretic peptide target?
distal convoluted tubules and collecting ducts of the kidneys
53
what part of the nephron does parathyroid hormone (PTH) target?
bone, distal convoluted tubule of the kidney and the intestines
54
what part of the nephron does aldosterone target?
distal convoluted tubules and collecting ducts of the kidneys
55
what part of the nephron does antidiuretic hormone (ADH) target?
collecting ducts of the kidneys
56
what is the stimulus for secretion of atrial natriuretic peptide?
stretching of the atria due to increased blood pressure
57
what is the stimulus for secretion of antidiuretic hormone (ADH)
increased blood solute concentration or decreased blood pressure
58
what is the stimulus for secretion of parathyroid hormone (PTH)?
falling blood Ca2+ levels
59
what is the stimulus for secretion of aldosterone?
renin-angiotensin-aldosterone mechanism (which is activated by decreased blood pressure or blood volume), elevated blood K+ or ACTH
60
parathyroid hormone is released when the body needs to _______ calcium levels and calcitonin is released when the body needs to _______ calcium levels
raise; lower
61
when the body becomes too acidic, how does the respiratory system try to compensate?
it increases the rate and depth of breathing
62
what are the three systems responsible for acid-base balance?
renal regulation, brain stem respiratory centers, and the chemical buffer system
63
what is the chemical buffer system?
the first line of defense for pH changes. it acts within a fraction of a second and is composed of one or more compounds that resist the dramatic pH changes caused by strong acids and bases
64
what is the brain stem respiratory centers?
the second line of defense for acid-base swings, which kicks in 1-3 minutes after the pH change
65
what is renal regulation in regards to acid-base balance?
the most potent mechanism for acid-base balance that takes days to work
66
what is an acid?
a substance that releases hydrogen ions in detectable amounts
67
which hormone has the largest effects on blood pressure and works to reabsorb water by retaining sodium?
aldosterone
68
what does a buffer do in a solution when the pH rises?
it releases hydrogen ions
69
water has a ___ way osmotic flow while nutrients/wastes/gases/ have a ___ flow
two; unidirectional
70
what happens when extracellular fluid osmolality increases?
water leaves the cell
71
what does a buffer do in a solution when the pH drops?
it binds hydrogen ions
72
water output is unavoidable. what are 3 wats the body loses water?
feces, sweat, and insensible water loss (via skin and lungs)
73
true or false: plasma osmolality increases with dehydration
true
74
the hypothalamus is the _____ center of the brain, which is the driving force for water intake.
thirst
75
what is responsible for stimulating the hypothalamic thirst center? (3)
- decreased blood volume or blood pressure - dry mouth - hypothalamic osmoreceptors
76
what body fluids would have the largest concentration of sodium ions?
blood plasma
77
vomiting, inappropriate use of diuretics or antacid abuse could lead to which of the following conditions?
metabolic alkalosis
78
when there is excess potassium in the human body, it is called _________.
hyperkalemia
79
what hormone can help the body retain water without influencing sodium levels?
anti-diuretic hormone (ADH)
80
what is a base?
a substance that takes up hydrogen ions in detectable amounts
81
identify the electrolyte: this ion is found primarily within the body's skeletal system, which is a reservoir for this electrolyte. its levels are largely controlled by parathyroid hormone (PTH)
calcium (Ca2+)
82
identify the electrolyte: the body's major anion, accompanying sodium in the extracellular fluid. it follows sodium out of the proximal convoluted tubule and is frequently coupled with it in the renal tubule
chloride (Cl-)
83
identify the electrolyte: the chief ICF cation, required for neuromuscular functioning and several metabolic activities. the heart is extremely sensitive to this electrolyte and disruptions in its level can cause sudden death. it is also part of the body's buffer system, entering as hydrogen ions are being secreted.
potassium (K+)
84
identify the electrolyte: the chief ECF cation, affected largely by aldosterone and atrial natriuretic peptide. it is central to fluid balance, electrolyte balance and overall body homeostasis
sodium (Na+)
85
what is an endocrine disorder where the adrenal cortex does not produce a sufficient amount of aldosterone?
addison's disease
86
true or false: electrolytes are mostly organic molecules that don't dissociate in water
false; non-electrolytes is what is being described
87
what hormone causes water retention during a certain phase of the female menstrual cycle and during pregnancy, similar to aldosterone?
estrogen
88
when the body becomes too acidic, how does the respiratory system try to compensate?
it increases the rate and depth of breathing
89
what is a buffer?
a substance that resists abrupt changes in the pH of body fluids
90
where is the majority of body fluid contained?
in the intracellular fluid compartment
91
what is metabolic acidosis?
a condition where blood pH falls below 7.35. it can be due to severe diarrhea, untreated diabetes mellitus, starvation or excessive alcohol intake.
92
what is metabolic alkalosis?
a condition where blood pH rises above 7.45. it can be due to vomiting, excess antacids, excessive aldosterone as a result of adrenal tumors or potassium-depleting diuretics.
93
what is respiratory acidosis?
a condition that results from hypoventilation, due to impaired lung function impaired ventilatory movement, brain stem injury or narcotic/barbiturate overdose
94
what is respiratory alkalosis?
a condition that results from hyperventilation. it can be caused by extreme emotions, hypoxemia, brain tumor, or injury
95
oogenesis is the production of ______.
female gametes (aka ovum)
96
when does oogenesis begin?
in the fetal period
97
what is a secondary oocyte?
a haploid cell containing nearly all the cytoplasm of the primary oocyte. it halts in metaphase II of meiosis before ovulation. there are two possibilities for this cell: 1. it is fertilized and completes meiosis II 2. the egg is not penetrated by a sperm cell + dies
98
what is the first polar body?
the cell created by meiosis I that has almost no cytoplasm or organelles. it is a small bundle of nuclear material
99
what is a primary oocyte?
a diploid cell that beings meiosis I again during the fetal period, but stops in prophase I and can resume years to decades later if at all. only the oocyte in the dominant follicle begins meiosis I again just before ovulation
100
what is a oogonium?
a diploid female stem cell that multiples rapidly during the fetal period. their number is determine b4 birth, when females have a lifetime supply. at birth there are around 7 million of these cells by the time a female hits puberty there will be around 400,000 remaining
101
what is the secondary polar body?
the haploid cell that can result from meiosis II if the secondary oocyte is fertilized it contains almost no cytoplasm because the relatively large ovum needs it all to ensure it has the nutrients needed to survive during the 6-7 day voyage to the uterus for implantation
102
what is an ovum?
a mature, haploid female reproductive cell that can be fertilized by a male gamete
103
progesterone has what functions? (6)
- promotes secretory phase of the uterine cycle - promotes production of viscous cervical mucous - increased levels post-ovulation cause the cilia to "beat" in the uterine tube to promote union of sperm & oocyte - works with estrogen to promote breast growth during puberty. during pregnancy it works with estrogen again to help the mammary glands mature - promotes diuresis - increases body temp
104
what are the functions of LH (luteinizing hormone)? (4)
overall: production of gonadal hormones in males: stimulates interstitial endocrine cells to secrete testosterone (needed for spermatogenesis) in females: triggers ovulation stimulates ovarian production of estrogen & progesterone
105
what are the functions of estrogen? (7)
- growth & maturation of reproductive organs & breasts during puberty - promote the proliferative phase of the uterine cycle - stimulate production of watery cervical mucus & fimbriae activity - promotes oogenesis & ovulation - promotes growth and enlargement of the uterus, external genitalia & mammary glands during pregnancy - stimulates Na+ reabsorption in renal tubules; enhance HDL levels & lower LDL levels - partially responsible for female libido
106
meiosis or mitosis? - produces daughter cells that are different than the parent cell - increases the level of genetic variation - involves two consecutive rounds of nuclear division, but only one round of DNA replication - forms tetrads - creates haploid cells - produces four daughter cells - occurs only in gametes
meiosis
107
meiosis or mitosis? - produces daughter cells that are identical to the parent cell - involves only one round of nuclear division - produces diploid cells - produces two daughter cells
mitosis
108
truth or false: testosterone is only present in males, while estrogen is only present in females
false
109
the uterus is composed of three distinct layers. which of the layers contracts during childbirth?
myometrium
110
what are the three cycles of the female menstrual cycle?
1. menstrual phase 2. proliferative phase 3. secretory phase
111
what is the menstrual phase?
days 1-5 of the menstrual cycle where the functional layer of the endometrium sloughs off. by around day 5 the developing ovarian follicles produce more estrogen and bleeding generally stops between days 3-6
112
what is the proliferative phase?
days 6-14 of the menstrual cycle where the functional layer of the endometrium regenerates and estrogen levels increase. ovulation will occur at the end of this phase of the menstrual cycle
113
what is the secretory phase?
days 15-28 of the menstrual cycle where the endometrium increases in size to ready for implantation and progesterone levels rise
114
what are the phases of the ovarian cycle?
1. follicular phase 2. ovulation 3. luteal phase
115
what is the luteal phase?
phase known for the activity that occurs within the corpus luteum, which is the portion of the follicle that remains in the ovary after ovulation. the corpus luteum secretes progesterone and some estrogen, but if pregnancy does not occur the corpus luteum degenerates into the corpus albicans in around 10 days, when luteinizing hormone levels drop. if pregnancy does occur in the corpus luteum will continue producing progesterone during the first three months of pregnancy
116
what is the follicular phase?
the phase that accomplishes vesicular follicle growth. the timing of this portion of the ovarian cycle varies, but is usually days 1-14. several follicles are initially selected to grow, but when FSH drops mid-phase only the ovum within the dominant follicle continues the process of growth and development
117
what is ovulation?
the process where an ovum is released from an ovary, usually around day 14 of the ovarian cycle
118
what are the functions of testosterone? (10)
- stimulates formation of male reproductive ducts, glands and external genitalia - promotes descent of the testes - growth of internal and external genitalia during puberty - maintains adult genitalia size + function - stimulates hematopoiesis (resulting in a higher hematocrit) - enhances BMR - libido - promotes aggression - secondary sex characteristics during puberty: promotion of long bone growth, along with increased skeletal and muscle mass and growth of the larynx and vocal cords for a deeper voice - enhances sebum secretion and hair growth
119
what is the epididymis?
the first portion of the male duct system that temporarily stores immature sperm. the sperm matures as it travels through this structure.
120
what is the bulbourethral glands?
structure that produces clear, thick mucus that cleanses the urethra of acidic urine prior to ejaculation and also serves as a lubricant during intercourse
121
what is the vas deferens?
structure with smooth muscle within its walls that create peristaltic waves during ejaculation to squeeze sperm fluid into the urethra
122
what is the urethra?
structure that carries both sperm and urine. sperm enters from the ejaculatory duct and urine enters from the bladder
123
what is the prostate?
a structure that encircles the upper urethra and secretes a milky white fluid that helps activate sperm
124
what are the seminal vesicles?
structures that produce the thick, yellow secretion that accounts for about 60% of semen. it contains fructose, vitamin C, prostaglandins and other substances that nourish and activate sperm
125
what is the testis?
the primary male sex organ that produces sperm, as well as testosterone
126
what is the vagina?
portion of the female duct system that begins at the cervical os. it receives the penis during sexual intercourse and serves as a passageway for menstrual flow from the uterus and birth canal
127
what is the uterus?
portion of the female duct system that receives, retains and nourishes a fertilized ovum. it is the size of a pear of pregnancy does not occur
128
what is an ovary?
organ responsible for producing ova, as well as cyclical production of the hormones progesterone and estrogen
129
what are the uterine (fallopian) tubes?
portion of the female duct system that provides the site for fertilization of an ovum. has fimbriae located near the ovaries to receive ovulated oocytes
130
what are the functions of FSH (follicle stimulating hormone)?
overall: production of gametes in males: stimulates sperm production in females: stimulates ovarian follicle maturation and ovarian production of estrogen
131
how long does spermatogenesis take to complete?
64-72 days
132
where does spermatogenesis begin?
within the seminiferous tubules of the testis
133
true or false: sperm is not formed until puberty, so it is absent during immune system development. as a result it is not recognized as a "self" cell and has to be kept separate from the rest of the body to keep it from being attacked by the immune system
true
134
what is the blood-testis barrier?
formed by tight junctions; similar to the blood-brain barrier. it prevents sperm antigens from escaping into the bloodstream and causing immune system activation
135
true or false: semen is a milky, white mixture of sperm and accessory gland secretions. it has an acidic pH to match the pH of the vaginal acid mantle
false; semen is alkaline to neutralize the acidic environment of the vagina. it contains the fructose needed to provide energy to sperm cells
136
oogenesis or spermatogenesis? - begins during the fetal period - lifetime supply of gametes present at birth - produces one viable gamete with up to three polar bodies - unequal division of cytoplasm among gametes formed by the stem cell - one gamete is chosen to continue to meiosis II each month - takes many years to complete
oogenesis
137
oogenesis or spermatogenesis: - begins during puberty - forms 4 viable gametes - takes approximately 64-72 days to complete in favorable conditions - occurs in the seminiferous tubules
spermatogenesis
138
what hormone is responsible for secondary sex characteristics in females?
estrogen
139
what are the female secondary sex characteristics?
- breast development - growth of axillary and pubic hair - increased body fat in hips and breasts - widening/lightening of the pelivs - onset of menses and the enlargement of female reproductive organs
140
what is anabolism?
the synthesis of large molecules from smaller molecules
141
what is catabolism?
the hydrolysis of complex structures to simpler ones
142
what is glycolysis?
the conversion of glucose provided by the blood or by stored glycogen into two pyruvic acid molecules, atp, and nadh. it is one of the three process of cellular respiration and is anaerobic
143
what is gluconeogenesis?
the conversion of glycerol and amino acids into glucose when too little blood glucose is available. it functions to protect the body from hypoglycemia and maintains a supply of glucose for the body cells that actually require it, like the renal medulla, erythrocytes, eye lens and part of the retina. the brain also relies on glucose until liver cells begin producing ketones
144
what is glycogenolysis?
glycogen is hydrolyzed into glucose molecules when blood sugar levels drop, occurring primarily in the liver. this is stimulated by the hormone glucagon and epinephrine, and it helps maintain blood sugar while fasting
145
what is lipogenesis?
the synthesis of triglycerides from glycerol and fatty acids that weren't immediately needed for energy. this process occurs when cellular atp and glucose levels are high, leaving the extra nutrients to be stored as fat.
146
what is ketosis?
a metabolic state where the body uses ketone bodies as an alternative energy source due to low carbohydrate availability
147
what is ketoacidosis?
when ketone bodies accumulate in the blood, leading to a drop in blood pH
148
what is metabolism?
the sum of all biochemical reactions inside a cell, involving nutrients
149
most vitamins act as __________, which means what?
coenzymes; they help enzymes in the body perform their functions effectively
150
what are water-soluble vitamins?
B + C; not stored in the body and need regular replenishment
151
what are fat-soluble vitamins?
A,D,E, + K; stored in body tissues and can accumulate to toxic levels if consumed excessively
152
what is basal metabolic rate?
the energy required by the body to perform only its most essential activities
153
what does higher body temperatures and stress do to BMR?
increase BMR
154
what is the body's thermostat?
hypothalamus
155
what happens when body temperature falls?
the hypothalamus activates the heat-promoting center which causes skin blood vessels to constrict, diverting blood to deeper tissues
156
what happens when body temperature rises?
the hypothalamus activates the heat-loss center which causes skin blood vessels to dilate, allowing heat to radiate away from the body.
157
absorptive or post-absorptive state: - occurs during and shortly after a meal - lasts about 4 hours - anabolism - nutrients are absorbed and stored - glucose is the primary energy source - excess carbohydrates, fats, and amino acids are stored as glycogen and fat - insulin plays a key role by enhancing glucose and amino acid entry into cells
absorptive state
158
absorptive or post-absorptive state: - occurs when the body relies on internal energy reserves - catabolism of stored nutrients provides energy - glucose is supplied through glycogenolysis, lipolysis, and gluconeogenesis - the brain may use ketone bodies during prolonged fasting - glucagon and the sympathetic nervous system mobilize energy reserves and stimulate gluconeogenesis
post-absorptive state
159
what are the three main stages of cellular respiration?
1. glycolysis 2. citric acid cycle (krebs cycle) 3. electron transport chain and oxidative phosphorylation
160
what is glycolysis?
the process where glucose undergoes glycolysis in the cytosol to produce two pyruvic acid molecules produces 2 atp
161
what is the citric acid (krebs cycle)?
the process where pyruvic acid is converted into acetyl CoA to enter the citric acid cycle in the mitochondrial matrix. it can also be fueled by fatty acids provided by lipolysis, as the breakdown produces of carbohydrates, fats, and proteins can all enter this cycle to be oxidized for energy produces 2 atp, 6 co2, + 10 coenzymes
162
what is positive nitrogen balance?
protein synthesis exceeds the rate of protein breakdown. while normal during pregnancy or adolescence it can also be expected after illness or injury when significant tissue repair is required.
162
what is the electron transport chain and oxidative phosphorylation?
the final catabolic reaction of cellular respiration that occurs on the inner mitochondrial membrane and directly uses oxygen and creates water. it ultimately attaches two phosphate groups to an ADP molecule, forming atp via oxidative phosphorylation. produces ~ 28 atp
163
what is negative nitrogen balance?
protein breakdown within the body exceeds the amount of protein synthesis. it can be caused by emotional stress, physical stress, or poor dietary protein intake or starvation
164
what are essential nutrients?
substances that the body cannot produce quickly enough to meet its needs so they must be obtained from the diet. include certain amino acids, fatty acids, vitamins, and minerals
165
what are complete proteins?
proteins, most often found in meat, eggs, fish, and milk, that meet the body's amino acid requirements for tissue maintenance and growth. the only plant sources of this type of protein are soybeans
166
true or false: nutritional ketosis is a dangerous metabolic condition that results from dangerously high levels of ketones and blood sugar that causes the blood to become too acidic. it is caused by uncontrolled type i or type ii diabetes, alcohol abuse, some illnesses, medications, or toxins. it occurs in the absence of insulin, which prevents the release of fatty acids.
false; ketoacidosis is being described
167
what is nutritional ketosis?
a metabolic state where fat provides energy for most of the body. it occurs when there is limited access to glucose: starvation, fasting, infancy, and pregnancy. as insulin decreases fatty acids are turned into ketone bodies. most of the brain can use ketones and gluconeogenesis provides glucose for the parts that require it.
168
what does the hypothalamus use as a heat-promoting mechanism?
- constriction of cutaneous blood vessels - shivering - increases metabolic rate - enhances release of thyroxine
169
what hormone completely directs activities during the absorptive (fed) state?
insulin
170
what are sources of blood glucose during fasted (post-absorptive) state?
- glycogenolysis in the liver - glycogenolysis in skeletal muscle - lipolysis in adipose tissue and the live - catabolism of cellular protein
171
what is the only organ that can "feed" your body when glycogen stores have been depleted?
liver
172
what happens to carbohydrates during the absorptive (fed) state?
- they are absorbed as monosaccharides - they are delivered to the liver - they are absorbed by capillaries within the small intestine - when released into the blood they enter cells to be metabolizes for energy, while excess is stored as glycogen in the liver or skeletal muscle - they can be converted to fats packaged with proteins to form VLDLs (very low density lipoproteins), which are released into the blood and picked up for storage by adipocytes
173
true or false: minerals provide the body with an important source of fuel
false; minerals are not used for fuel, but work with other nutrients to help the body function
174
what are some functions of minerals?
- hardening bone (calcium, phosphorous, and magnesium) - blood electrolytes (sodium and chloride) - nerve function (sodium, potassium, and chloride) - thyroid hormone synthesis (iodine) - binding oxygen to hemoglobin (iron) - acid-base balance (phosphorous and potassium) - co-factor (manganese)
175
true or false: during cellular respiration a glucose molecule is oxidized to co2, h20, atp, + heat
true
176
where does glycolysis occur?
in the cytosol
177
where does the citric acid (krebs) cycle occur?
mitochondrial matrix
178
where does the electron transport chain occur?
inner mitochondrial membrane
179
list the steps of cellular respiration in order:
1. glycolysis 2. citric acid (kreb's) cycle 3. electron transport chain 4. oxidative phosphorylation
180
what is glycogenesis
glucose is synthesized into glycogen when there is an adequate amount of atp and blood sugar is adequate, stimulated by the hormone insulin. this happens most often in the liver and skeletal muscle, due to the fact that they are most active in glycogen synthesis
181
what is metabolic rate?
the total heat produced by chemical reactions and mechanical work of the body
182
oxidation reaction is?
the type of reaction that causes the loss of electrons and therefore energy
183
reduction reaction?
the type of reaction that causes a substance to gain electrons, and therefore energy
184
what is cellular respiration?
the catabolic breakdown of food duels whereby energy from food is captured to form atp within cells
185
what three groups can macronutrients be broken down into?
carbohydrates, proteins, and lipids
186
lipids serve what functions?
- provide insulation - energy storage - important component of phospholipids - important component of myelin sheaths - stabilizes plasma membranes - serves as a precursor for bile salts - helps form the steroid hormones produced by the adrenal cortex and gonads - component of prostaglandins - provide the main energy source for skeletal muscle and hepatocytes - help the body absorb fat-soluble vitamins
187
what is glucose-sparing?
how the body can adjust to burn more fats during prolonged fasting
188
what tissue does lipolysis begin in?
adipocytes
189
what is the growth hormone
anabolic hormone accelerating protein growth and synthesis during childhood, while conserving protein during adult hood
190
what is the all-or-none rule?
refers to the idea that all amino acids needed to build a protein at any given time must be present in adequate amounts in order to construct the protein. if unused essential amino acids aren't stored. they're converted to carbs or fats, or oxidized
191
what is nitrogen balance?
term used to describe protein homeostasis in the human body when protein breakdown and protein synthesis occur @ the same rate
192
what is cortisol?
catabolic hormone causing protein breakdown and the conversion of amino acids to glucose
193
what are incomplete proteins?
proteins lacking one or more of the essential amino acids needed to build a new protein. these proteins are generally provided by beans, nuts, and cereal grains
194
somatic cells (body cells) have ___ chromosomes (__ pairs), while gametes (sperm or egg) have __ chromosomes.
46;23;23
195
the parasympathetic nervous system leads to ________, while the sympathetic nervous system leads to _________.
erection; ejaculation/orgasm
196
what is a mature follicle that ovulates?
graafian follicle
197
what secretes progesterone, post-ovulation?
corpus luteum
198
what is inactive fibrous scar tissue?
corpus albicans
199
damage to the glomerulus could contribute to which abnormal urine finding?
protein
200
what is the purpose of cellular respiration?
generate atp
201
an increase in glomerular blood pressure:
increases the amount of filtrate entering the nephron
202
when there is a respiratory obstruction, it can result in ________.
respiratory acidosis
203
parathyroid hormone is closely linked to the maintenance of ______ levels in the body
calcium
204
which male hormone stimulates spermatogenesis and male secondary sex characterstics?
testosterone
205
presence of the hormone ______ prevents the body from accessing fat stores to use as energy
insulin
206
leptin has what effect on the body?
suppresses appetite and increases energy expenditure
207
which adrenal hormones increase blood glucose, fatty acid, and amino acid levels to deal with stress
glucocorticoids
208
lipolysis involves _________.
breaking down triglycerides into fatty acids and glycerol
209
individuals need to ingest _____ to maintain tissue maintenance and growth.
complete proteins
210
which hormone is suppressed by alcohol consumption and increases urination as a result?
ADH
211
the level of ______ in the body is closely tied to the body's water volume.
sodium
212
potassium is mainly found in which fluid compartment?
intracellular fluid
213
the bulbourethral gland produces ______.
clear thick mucus
214
spermatogenesis produces ___ viable sperm, while oogenesis produces ___ viable ovum.
4;1
215
the amount of energy the body uses at rest is referred to as _____.
basal metabolic rate
216
fat synthesis that occurs when glucose levels are elevated and cellular ATP levels are high is:
lipogenesis
217
which organ system is responsible for regulation of blood composition, volume, and pressure?
urinary
218
aquaporins are inserted into the apical membrane of collecting duct principle cells when _____.
adh levels are high
219
after eating a meal high in sodium, what would occur?
temporary increase in blood volume
220
once an oocyte is ovulated, it is received directly by the _______.
fimbriae
221
prolactin levels are most elevated in ________>
lactating females
222
which nutrient serves a coenzyme function?
vitamins
223
using non-carbohydrate molecules to form glucose is called:
gluconeogenesis
224
aldosterone helps regulate _____.
sodium ion concentration in extracellular fluid
225
the hormone _____ can cause edema, similar to aldosterone.
estrogen
226
which two cells have the same # of chromosomes?
ovum and sperm
227
one form of birth control is a ______. where they surgically cut the _______.
vasectomy; vas deferens.
228
which process provides the greatest ability to change blood pressure over time?
renal regulation
229
which part of the brain acts as the body's thermostat?
hypothalamus
230
if the efferent arteriole exiting the glomerulus vasoconstricts, it would cause ______.
increased urine output
231
atria produce ______ & the adrenal cortex produces ______, which both act on the DCT of the nephron
anp; aldosterone
232
growth of breasts at puberty and widening of the pelvis in females is due mostly to ______.
estrogen
233
male ejaculation is under the control of _____
a sympathetic reflex
234
the corpus luteum produces _______.
progesterone after ovulation
235
lower blood plasma volume, increased urination and decreased blood pressure could be from ______.
ingestion of a diuretic