HAN 202 Test 2 Flashcards
1
Q
renal cortex
A
a glandular superficial region
2
Q
2 parts of a nephron
A
- renal corpuscle
- renal tubule
3
Q
juxtamedullary nephrons
A
- long loops
- deep into the medulla
- outside the cortex
- production of concentrated urine
- efferent arteriole supplies vasa recta
4
Q
nephron capillary beds: peritubular capillaries
A
- low pressure
- porous
- meandering
- associated with cortical nephron
5
Q
nephron capillary beds: vasa recta
A
- long and straight vessels loops of Henle
- juxtamedullary nephrons
- formation of concentrated urine
6
Q
renal tubule
A
- glomerular capsule
- proximal convoluted tubule (PCT)- reabsorption and secretion
- descending and ascending limbs
- distal convoluted tubule- secretion
- collecting duct- receives filtrate from many nephrons
7
Q
juxtaglomerular complex
A
- one per nephron
- regulation of filtrate formation and BP
- distal portion of the ascending limb of the loop of henle
- AFFERENT (sometimes efferent) arteriole
- granular cells in the AFFERENT arteriole that secrete renin
8
Q
juxtaglomerular complex- macular dense cells
A
-ascending limb of tubule
9
Q
filtration membrane
A
- fenestrated endothelium (pores) of the glomerular capillaries
- visceral membrane of the glomerular capsule (podocytes)
- basement membrane- negatively charged basement membrane repels large plasma proteins
10
Q
3 glomerular filtration rate factors
A
- net filtration pressure
- total surface area (large)
- membrane permeability
11
Q
extrinsic controls: sympathetic nervous system
A
- under extreme stress (low BP shock - need to maintain BP):
- norepinephrine and epinephrine are released
- constriction of afferent arterioles -> inhibit filtration of afferent arterioles -> inhibit filtration -> renin is released
12
Q
angiotensin 2
A
- constricts arteriolar smooth muscle, causing MAP to rise
- triggers aldosterone secretion from adrenal cortex- stimulates the reabsorption of Na+ (Na moves into blood, water follows, conserves blood volume)
- stimulates the hypothalamus to release ADH (antidiuretic hormone) and activates the thirst center
13
Q
resabsorptive capabilities of renal tubules and collecting ducts
A
- PCT- site of most reabsorption (ions, water, nutrients)
- loop of henle- descending limb- H20
- ascending limb- Na, K, Cl
- DCT and collecting duct:
- hormonally regulated
- Na- aldosterone
- water- ADH
- Ca- parathyroid hormone
14
Q
diuretics
A
- chemicals that enhance the urinary output
- osmotic diuretics- substances not reabsorbed (e.g. high glucose in a diabetic patients, water follows glucose)
- ADH inhibitors such as alcohol
- substances that inhibit Na reabsorption and obligatory H2O reabsorption such as caffeine and many drugs
15
Q
steroids
A
-gonadal and adrenocortical
16
Q
mechanisms of hormone action
A
- alter plasma membrane permeability of membrane potential by opening or closing ion channels
- stimulate synthesis of proteins or regulatory molecules
- activate or deactivate enzymes systems
- induce secretory activity
- stimulate mitosis
17
Q
3 plasma membrane components
A
- receptor
- g protein
- enzyme
18
Q
adrenal cortex
A
- zona glomerulosa- mineralocorticoids (aldosterone)
- zona fasciculata- glucocorticoids (cortisol) -> in response to ATCH
- zona reticularis- gonadocorticoids
- mineralocorticoids and glucocorticoids -> long term stress
19
Q
thyrotropin
A
thyroid stimulating hormone
20
Q
adrenocorticotropic hormone (corticoptropin)
A
- stimulates the adrenal cortex to release corticosteroids (glucosteroids)
- regulation of ACTH release:
- triggered by hypothalamic corticotropic releasing hormone (CRH) in a daily rhythm
- internal and external factors such as fever, hypoglycemia, and stressors can alter the release of CRH
21
Q
ADH
A
- if solute concentration is high -> ADH is synthesized and released
- ADH targets collecting ducts and inhibits urine formation
- ex. (dehydration) water loss -> high osmotic pressure of blood stimulates hypothalamus -> posterior lobe of pituitary -> ADH secretion -> kidney -> water retention -> osmotic pressure decreases -> inhibits release to hypothalamus
22
Q
thyroid gland
A
-colloid (thyroglobulin + iodine) stored in the lumen of the follicles and is the precursor of T3/T4
23
Q
parathyroid
A
- four to eight tiny glands located behind thyroid (not related)
- contain chief cells that secrete parathyroid hormone (PTH)
- low levels of this hormone will result in tetany
- PTH activates osteoclasts
- reabsorption in kidney tubules
- promotes kidney’s activation of vitamin D which increases Ca2+ absorption from food
24
Q
cushing syndrome
A
-increase in glucocorticoid from ACTH-releasing pituitary tumor or from clinical administration of glucocorticoid drugs
25
Q
addison’s disease
A
- deficits in glucocorticoids and mineralocorticoids
- lose weight
- hypotension
- dehydration
26
Q
adrenal medulla
A
- chromaffin cells secrete epinephrine (80%) and norepinephrine (20%)
- epinephrine- metabolic activity, bronchial dilation, blood flow
- norepinephrine- peripheral vasoconstriction and BP
- short term stress
27
Q
pancreas
A
- acinar cells- (exocrine) - enzyme for digestion
- pancreatic islets- (endocrine)
- alpha cells- glucagon (hyperglycemic) -> glycogenolysis, gluconeogenesis
- beta cells- insulin (hypoglycemic)
28
Q
endocrine gland
A
-a ductless gland that empties its hormone into the extracellular fluid, from which it enters the blood
29
Q
essential fatty acids- lipids
A
- omega-3 and omega-6
- found in most vegetable oils
- cannot be synthesized by the liver
30
Q
use of lipids
A
- absorption- fat soluble vitamins
- fuel- hepatocytes and muscle
- cell membranes and myelin sheath
- fatty deposits
- regulatory function of PROSTAGLANDINS- control BP, MM, inflammation
- cholesterol- stabilizes plasma membranes and precursor of bile salts and steroid hormones
31
Q
uses for proteins
A
- structural material- keratin, collagen, elastin, muscle proteins
- most functional molecules- enzymes, some hormones
- nitrogen balance- rate of protein synthesis = rate of breakdown
- hormonal controls- anabolic hormones (GH, sex hormones) accelerate protein synthesis
32
Q
how many amino acids can the body produce
A
12/20
-8 are essential
33
Q
insoluble and soluble vitamins
A
- vitamins are coenzymes
- water soluble- BC -> need to be ingested daily
- fat soluble- ADE and K -> stored in body except K
34
Q
minerals
A
- calcium, phosphorus, and magnesium salts -> harden bone
- iron -> oxygen binding to hemoglobin
- iodine-> thyroid hormone synthesis
- sodium and chloride -> electrolytes
- Na -> fluid retention and high BP
35
Q
3 stages of metabolism
A
- digestion, absorption and transport to tissues
- cellular processing (cytoplasm) -> anabolism into proteins, carbs, or lipids OR catabolism into intermediates
- oxidative (mitochondria) breakdown of intermediates into CO2, water, and ATP
36
Q
Krebs (citric acid) cycle
A
- mitochondrial matrix
- fueled by pyruvic acid and fatty acids
- pyruvic acid is broken down into CO2 in a series of energy extracting reactions
- breakdown products of fats and proteins can also enter the cycle
- primary roles is to generate electrons (H)
- transitional phase- 2 NADH* and 2 CO2
- 2 ATP
- 4 CO2
- 6 NADH*
- 2 FADH*
- electron transport
37
Q
forms of breaking down and synthesizing glucose and glycogen
A
- glucogenesis- glycogen formation when glucose supplies exceed need for ATP synthesis -> liver and muscle
- glycogenolysis- glycogen breakdown in response to low blood glucose
- gluconeogenesis- glucose synthesis from noncarbohydrate molecules (glycerol and amnio acids) -> liver
- lipogenesis- triglyceride synthesis when ATP and glucose levels are high (glucose -> fat)
- lipolysis- converts fats to glycerol and fatty acids for fuel -> liver, cardiac, and skeletal muscle
38
Q
lipid metabolism
A
- fat catabolism yields 9 kcal per gram (vs 4 kcal per gram of carbohydrate or protein)
- most concentrated source of energy
- blood glucose- energy for a few minutes
- glycogen stores- energy for a day
- lipid stores- 30-40 days
- lipolysis into fatty acids and glycerol
- glucose produces 32 ATP
- common fat produces 463 ATP
- only triglycerides are routinely oxidized for energy
- glycerol pathway- glycerol enters into glycolysis
- fatty acid pathway- fatty acids enter the kreb (citric acid) cycle
39
Q
protein metabolism
A
- amino acids are recycled
- proteins are NOT stored in the body
- excess proteins are oxidized for energy OR converted to fat for storage
- transamination (NH2 switched from amino acid to keto acid) -> converted to: pyruvic acid -> keto acid intermediate of krebs cycle
- deamination of AA is necessary for the carbon skeleton to enter catabolic pathways
- oxidative deamination- amine of glutamic acid is removed as ammonia and combined with CO2 to form urea
- keto acid modification- keto acids formed are altered so they can easily enter krebs
- the nitrogenous compounds -> waste products
40
Q
absorptive state (FED)
A
- 4 hours after eating
- anabolism exceeds catabolism
- glucose converted to glycogen or fat
- glycerol and fatty acids converted to triglycerides -> adipose tissue
- amino acids are used in protein synthesis and excess is deaminated -> stored as fat or used for ATP
- insulin is in control
- STORAGE
41
Q
post absorptive state
A
- catabolism exceeds anabolism
- utilizes glycogen and fat stores first -> then move to muscle protein
- glycogenolysis in liver and muscle
- lipolysis in adipose and liver
- glycerol used for gluconeogenesis in liver
- glucagon is released -> glycogenolysis and gluconeogenesis
- proteins -> amino acids
- glycogen -> glucose
- triglycerides -> glycerol and fatty acids
42
Q
the process whereby excess glucose is stored in cells
A
-glucogenesis
43
Q
hepatocytes
A
- process nearly every class of nutrient
- regulate plasma cholesterol levels
- store vitamins and minerals
- metabolize alcohol, drugs, hormones, and bilirubin
44
Q
lipoproteins
A
- transport water insoluble cholesterol and triglycerides in blood
- VLDLs- transport triglycerides from liver to peripheral tissue (adipose)
- LDLs- (bad)- transport cholesterol to peripheral tissues for membranes, storage, or hormonal synthesis
- HDLs- (good)- transport excess cholesterol from peripheral tissue to liver to be broken down and secreted into bile
- unsaturated fatty acids- enhance catabolism of cholesterol
- saturated fatty acids- enhance synthesis of cholesterol
45
Q
BMI
A
weight x 705/height (inch)^2
46
Q
short term vs long term regulation of food intake
A
SHORT TERM
-vagus nerve suppresses hunger center
-increased nutrients in blood suppress eating
-ingesting sugar sets of the brains reward (pleasure) center releasing dopamine, this may be genesis for overeating
-gut hormones (e.g. insulin and CCK) depress hunger
LONG TERM
-leptin secreted by fat cells in response to increased body fat mass -> lowered appetite
47
Q
sperm penetration
A
- sperms needs to pass 2 layers: corona radiata and zone pellucida
- sperm is capacitated
- acrosomal process forms and binds to receptor on zona pellucida
- Ca levels within the sperm increase
- Ca activates oocyte to prepare for 2nd meiotic division and…
- cortical reaction- zonal inhibiting proteins (ZIPS) to prevent other sperm from entering
48
Q
evolution of zygote
A
- zygote
- blastomeres (36 hours) - 2-8 cells
- morula (72 hours)- 16 or more cells
- blastocyst (4-5 days)- fluid filled hollow sphere -> this reaches the uterus to implant
49
Q
blastocyst- two types
A
- trophoblast cells- single layer of flat cells that are immunosuppressive and participate in PLACENTA formation
- inner cell mass- becomes the EMBRYONIC disc
50
Q
implantation
A
- blastocyst floats for 2-3 days- nourished by uterine secretions
- implantation begins 6-7 days after ovulation
- trophoblast adheres to the endometrium
- secrete enzymes which irritate the endometrium
- if implantation fails the blastocyst is aborted
- a minimum of 2/3 of zygotes fail to implant
51
Q
human chorionic gonadotropin (hCG)
A
- secreted by trophoblast cells, and later the chorion
- causes corpus luteum to continue to secrete estrogen and progesterone
- hCG rises until end of 2nd month -> placenta begins to secrete
52
Q
placentation
A
- embryonic tissues- the chorion (develop from the inner cell mass) (baby)
- maternal tissue -> decidua basalis (comes from mom)
- mother and baby’s blood supply lie close but do NOT intermix
53
Q
chorionic villi
A
-grow into blood-filled lacunae (maternal)
54
Q
gastrulation
A
- during implantation, the blastocyst starts to convert to a gastrula
- inner cell mass develops into the embryonic disc (subdivides into epiblast and hypoblast)
- extraembryonic membranes develop (week 3)
- embryonic disc (2 layer) becomes a 3 layered embryo (endoderm, mesoderm, and ectoderm)
- appearance of primitive streak (dorsal groove)
- notochord: mesodermal cells and form axial support
55
Q
extraembryonic membranes
A
- amnion- form amnionic sac
- yolk sac- forms part of digestive tube
- allantois- umbilical cord
- chorion- helps form the placenta
- all formed within first 2-3 weeks of development
56
Q
organogenesis
A
- formation of body organs at 8th week
- end of embryonic period
- neurulation is the first event
- gives rise to brain and spinal cord
- neural plate folds inward as a neural groove and fuse into neural tube
- neural crest cells- cranial, spinal, and sympathetic ganglia, and adrenal medulla
57
Q
fetal blood circulation
A
- first blood cells arise in the yolk sac
- by the end of the 3rd week embryo has a system of paired vessels and can hear babys heart beat
- unique vascular modifications
- **umbilical arteries (deoxygenated blood) and umbilical vein (oxygenated blood)
58
Q
relaxin
A
-relaxin- (placenta) causes pelvic ligaments and the pubic symphysis to relax to ease birth passage
59
Q
tidal volume
A
- increases
- dyspnea
- in later pregnancy
60
Q
labor
A
- fetal secretion of cortisol stimulates the placenta to secrete more estrogen
- causes production of oxytocin receptors
- oxytocin causes placenta to produce prostaglandins -> vigorous contractions
- surfactant protein A from fetal lungs causes softening of the cervix
- dilation- engagement of head; 10 cm
- expulsion- crowning and delivery
- placental- delivery of placenta 30 mins after
61
Q
neonatal period
A
- 4 weeks after birth
- APGAR:
- heart rate
- respiration
- color
- muscle tone
- reflexes
- 0-2 points each
- 8-10 score is healthy
62
Q
first breath
A
- increase CO2 -> central acidosis -> stimulates respiratory control centers to trigger the first inspiration
- surfactant in alveolar fluid helps reduce surface tension
- respiratory rate- about 45 per minute for first two weeks, then declines
- premies usually put on respirators, lungs still immature
63
Q
letdown reflex
A
- oxytocin causes this
- actual ejection of milk from mammary glands
- colostrum- yellowish secretion rich in vitamin A, protein, minerals, and IgA antibodies -> released in the first 2-3 days
