MIDTERM 3 PORTION - new stuff Flashcards
What are the three types of nutrients used for catabolism to make ATP
fatty acids, amino acids, glucose
What do amino acids, fatty acids and glucose become thru anabolic metabolism?
amino acids - proteins
Fatty acids - fat (adipose tissue)
Glucose - Glycogen (muscle and liver)
WHat is metablism?
Chem rxns of breakdown and synthesis
What is catabolic metabolism?
Breaking down a substance into smaller parts. Net result: energy release
What is anabolic metabolism>
Smaller compounds joined to make a larger compound. Net
result: energy use.
* The body uses anabolic reactions to store molecules for energy, and to support growth,
maintenance, repair
- Amino Acids Proteins
- Fatty Acids Fat (Adipose tissue)
- Glucose Glycogen (in muscle and liver)
Can we store protein?
No - any excess amino acids are converted to glucose or fatty acids
What is glycogensis? Lipogensis? what type of rxn are they? What is their goal?
in liver and skel muscle - glucose - glycogen stores
Anabolic rxns
Goal to restore blood glucose and store excess nutrients
What is Glycogenolysis and Lipolysis? What type of reaction are they? what is their goal?
breaking down glycogen to glucose, breaking down fat (lipid triglycerides) to fatty acids/glycerol. Catabolic rx - goal: maintain blood glucose level and energy supply for cells
Describe how glycogen gets to atp
Glycogen thry glycogenolysis become glucose then thru glycolysis/cac/etc becomes atp
what is aroudn teh net result of catabolism of one glucose molevule?
32 atp
explain how fat (triglycerides) become ATP?
Thru lipolysis becomes fatty acids and glycerol then thru beta oxidation/cac/etc becomes atp
where does betaoxidation teake place?
mitochondira
what does beta oxidation produce in the liver?
ketone bodies - can be used fot atp prof in cels and body
what is the net result of catabolism of 1 fatty acid molecule?
upwards of 100 atp - depding on FA chain
How do proteins become ATP?
Proteins become amino acids theen thru transamination become - acetylcoa, pyravte/glycose or other amino acids which then become atp
What is the purpose of anabolic metabolism?
Nutrient storage/synthesis, synth of other elements or meolecules liek proteins ,phospholipids and nucleic acids
When does nutrient storage take place?
When nutrient intake is grater than metabloci needs and we need to build a supply of nutrients for the post absorptive (fast) state
WHat are the 2 main storage forms of energy?
GLycogen + adipose tissue
What is glycogen composed of and where is it stored?
stored in liver and skeletal muscles and glycogen is many glucose molecules bound together
What are some exampls of moelcules that an be used to make glucose (other than glycogen)?
glycerol, pyruvate,l actate, some amino acids
What is lipogenesis?
Process used to make fatty acids and glycerol (from glucose) and/or to store triglycerides in adipose
─ Enzyme required to make new Fatty Acid chains: Fatty Acid Synthase – catalyzes the
reaction of adding 2-Carbon units together to make a fatty acid chain.
─ Fatty acid chains are attached to glycerol and assembled into triglycerides in the
Endoplasmic Reticulum in adipocytes and then stored there
Where are fatty acids assembled into triglycerides?
endoplasmic reticulum
What are two ways that amino acids can be converted thens stored?
stored as glycogen - some amino acids (glucogenic) conv to glucose and stored as glyc
Stored as fat - some ketogenic can be convertws to fatty acids athen stroed in adipose tissue
what are the two metabolic states?
absorptive state (fed)
- as soon as nutrients absorbed from
Postabsorptive state (fasted
- no more nurtients available from diet
catabolic metabolism dominates
glucagon trigers catabolic metabolism
What is the function of the kidneys?
4 main ones
filter blood to remove metabolic waste products
Modify blood plasma to maintain homesotasis of water + solute, electrolyte/acid base and BP
Reg prod of red blood cells by releasing erythropoetin
Activate vit D
where does urine exit the bladder
urethra
What 3 parts make up the urinary tract?
ureters, urinary bladder, urethra
what does the bladder do?
store urine
what do ureters do?
transport filtrate from kidneys to bladder
What are the three parts of the kidney and what do each do?
renal cortex and renal medulla is where filtrate is collected from blood and turned to urine
Renal pelvis is where urine produced by nephrons is collected and drained
What is the functional unit of the kidney?
the nephron
What are the two main parts of a nephron?
renal corpuscle and renal tubule
Explain the path of blood low thrut he kdiney from steps 1 to 13
Renal artery - segemental artery - interlobar artery - arcuate artery - interlobular - afferent arteriole - glomerulus - efferent arteriole - peritubular capillaries - interlobular vein - arcuate vein - interloabr vein
What are the 5 parts of the nephron from beginning to end?
renal corpuscle - prox tubule - nephron loop - distal tubule - collecting duct
What is the renal corupuscle and what is it composed of?
It is where blood filtrate enters the kidney -
composd of glomerulus - fenstrated (leaky) capillaries
and glomerular capsule - recieves filtrate from the capillaries - inner visceral layer and outer parietal
What does the collecting duct do?
collects filtrate from distal tubules and modifies it before it exits kidney - where filtrate becomes urine
Where are juctagloerular cells found?
afferent and efferent arterioles
what are the two types of cells found in the juxtaglomerular apparatus ?
juxtaglomerular cells and mcaula densa cells
where are macula densa cells found
in the juxtaglomerular apparatus they are found in the nephron tubule right next to the glomerulus
what does the juxtagolernylar appareatus regulate?
BP and Glomerular filtration rate
What is glomerular filtration rate?
The amount of fitrate entering into both kidneys in one min
What are the 3 processes carried out by the nephron?
Glomerular filtration
- substances from blood filtered ino renal capsule based on size
- cells and larger proteins are too big and remain in blood and smaller substances like water, electrolytes acid/bases
Tubular reabsorption
- filtrate modified based on bodys needs
- most water, glucose, amino acids and electrolytes returned into blood
- further cary amount of diff substances that is reabsorbed based on the body’s needs
Tubular secretion
- mores substances are added into filtrate for excretion
- maintenance of electrolytes
- removal of toxins missed during filtration
GLomerular
Where does golermular filtration take place
In the renal corpuscle, filtrate enters here
What are the three layers of glomerular filtration?
- fenestrated glomerular capilarry endothelial cells
- Basal Lamina - collagen fibers
- Podocytes - visceral layer of epethelial cells of glomerualr capsule
What substances are filtered into the glomerular capsule
water, ions, glucose, amino acid s
What is the filtration Fraction?
the percentage of blood plasma that passes thru the glomerular 3 ply filtration membrane and becomes filtrate
what is the average filtration fraction
20%
About ____ of plasma that fflows thru glomerulus enters the capsular space
1/5
What 3 forces determine glomerular filtration rate?
glomerular hydrostatic pressure
capsular hysdrostatic pressure
glomerular colloid osmotic pressure
What is glomerular hydrostatic presssure? What is it mainly determined by? What does it do?
the force of blood against the filtration membrane. Mainly determined by systemic bp.
IT pushes blood INTO the capsule
what is the average glomerular filtration rate
125ml/min
What is capsular hydrostatic pressure? What does it do?
Force of filtrate pushing back against filtration membrane. Pushes filtrate BACK into the glomerular capillaries
What is glomerular colloid osmotic pressure. Where is it higher?
The force created by proteins in the plasma - higher in capillary plasma then in the filtrate - osmotic pressure drives water back into capillaries
Which forces favour filtration and which oppose it?
Glomerular hydrostatic pressure favours filtration whil capsular hysdrotstaic filtrationa dn glomerular colloid osmotic pressure oppose filration
In Overall (net) filtration is fluid driven out or into glomerulus and how much>
10mmHg of pressure is driven OUT of glomerulus overall
What are the 2 way glomerular filtration rate can be regulated?
Autorgeulation (reg from wihtin kidney) and hormonal mechanisms
what does auto regualtion allow and what are the 2 types?
allows the GFR to remain reletively constant despite fluctuaion ins SBP
2 types - myogenc mechanism and tubuloglomerular feedback
What is the myogenic mechanism of glomerular filtration reate in autoregulation?
Smooth msucle in afferent and efferent arterioles vasoconstrict/vasodilate in response to changes in systemic blood pressure
What is tubuloglomerular feedback
as GFR increases, volume of filtrate floing thru renal tubule and macula densa cells increases
- macula densa cells repsond by releaseing naccarines that cayse vasocontriciton of afferent arteriole and vasodilation of efferent (opposite when gfr decreases)
What are the two types of horomonal regulation of the GFR?
The renin-angiotensin-aldosterone system
atrial natriuretic peptide
What is the renin angiotensin aldosterone system? WHat is its primary goal? What is it initiated by?
what is this release stimualtated bY?
main goal to maintain systemic blood pressure, secondary goal of maintaining GFR. initiated by release of renin from juxtaglomerular cells
stimualted by
- symp NS
Low glomerular hydrostatic pressure (due to low BP)
stimulation from macula dense cells
Where is atrial natriuertic peptide released? in repsons to what?
released by cells in the atria of the heart on repsonse to increaesed blood volume
Increases the GFR by causing casodilation of aff and vasoconstriciton of efferent arterioles so that more filtrate enters glomerslus
Also increase excretion of urine which decreases blood volume and blood pressure
what is the pathwayof filtrate as it becomes urine?
Glomerular Capsule (renal corpuscle) proximal tubule nephron loop distal tubule collecting duct
______________ is a Hormone secreted from
Juxtaglomerular cells of the afferent and
efferent arterioles in response to __________
Glomerular Filtration Rate. This is due to a
______________ in blood pressure.
Renin, low, low (decrease)
What is paracellular transport vs transcellular transprot?
Paracellular is betweem cels and can fit smal ionns and water thru simple diffusion and osmosis
Transcellular is across cells and must be mediated by a carrier - glucose, amino acids, Na+, K+
Seretion is always _____ and mediated by____
transcellular and meditated by carriers
Where is most filtrate imeediatly absorbed from?
proximal tubule
Where are the 2 places taht H20 is reabdobred by osmosis? More reabsorbed in distal tubule and ollcting duct
Prox tubule and nephron loops
Where does ADH and aldosterone act? What do each do
ACt in the distal tubule and collecting duct
Anti-diuretic hormone stimulates water reabsoprtion at above
Aldosterone stimulates Na+ reabsprption in distal tubule and H20 is reabsorbed by osmosis if ADH also present
Where is glucose reabsorbed? How?
proximal tubule
Na= and glucose symproters use energy od Na+ gradien to bring glucse and Na+ from prox tubule to intersititial fluid via facillitated diffusion and then diffusees into preitubular cappilary
How is water reabsorbed in proximal tubule?
solute concentration gradient drices water inton tubule cell thru aquaporin channels via osmosis
What is vasopressin also known as
ADH
With lots of ADH/vasopressin what happens to collecring duct and urine? What happens with littel/absense_
with lots the collecting duct is freely permeable to water so water leaves by osmosis into capillaries and urine is concentrated.
absense of adh means collecting dut is impermeable to water and urine is filute
Describe pathway of adh? Where is it produced? where does it go?
Produced in hypothalamus - psot pituaitry then to distal tubule and connecting duct where H20 is reabsorbed
What two things increase aldosterone secretion
Increased K+ in bood
Decreased bp, incr renin secretion and angiotensin II
Where is aldosterone secreted?
adrenal cortex
What 2 main things does aldosterone do?
Na+ reabsorption (and water)
K+ secretion
Where along the nephron is water
reabsorption regulated by ADH?
distal tubule and colelctign duct
Which of the following is NOT typically brought
into the nephron by secretion?
glucose
Atrial Natriuretic Peptide (ANP) inhibits the release of ADH and Aldosterone… WHY?
ANP responds to increase in BP and BV and increases GFR (by incr vasodil of aff and casoconstric of eff) this incraes excreiton pf urine (dieuresis) - aldosterone and adh increase BV and BP by increasing Na= an h20 reapsotion so this iis inhibited
What things does urine contains
water ,sodium potassium, chloride, hydrogen ions, phosphates, Sulfates
* Metabolic wastes such as urea, creatinine, ammonia,
and uric acid
* Small amounts of bicarbonate, calcium, and magnesium may also be present
What two types of fluid does body consist of?
Extracellular fluid
- blood plasma and interstitial fluid
Intracellular fluid
Typical 20-30YO 154lb male has _____ total body wate
60%
What are electrolytes
susbtacnes that dissaciate inton ions when placed in water
is glucose an elctrolyte
no
What are teh 2 types of water loss?
Sensible - urine and feces
insensible (unnoticeable) - sweat and evaporation from expired air
What is obligatory water loss?
minimum amount of
urine that must be produced per day in order to maintain
healthy function and homeostasis
F
What are the main 3 ways water is gained from most to least
ingested from liquidds
ingested from food
formed by. metabolism
What 2 stimuli in the body trigger thirst?
osmolarity of blood plasma - increases trigggers thrist i. hypothal
volume of blood plasmsa - decreases and triggers thrist in the hypothal
Where is adh produced and released
produced in hypothal and released by post. pit
What does electrolyte homesostasis in the body mean?
Maintaining disequillibrium between intracellular and extracellular fluid
What 2 hormones increase Na+. retention and what hormone decreases Na+ and water reabsorption?
2 hormomes tha tincreae Na+ retention are Aldosterone and angiotensin II
one that decrease Na+ and water reabsoprtion.= ANP (Atrial natriuretic peptide
Hormone
What is Na+ concentration detemined by
Na+ and water contetn
what hypernatremia vs hyponatremia?
hypernatremia is high plasma Na+ >145
Hypo low <135mEq/l
What is the main intracellular cation? What is the main extracellular cation?
Intracellular is K+ and Na+ = extracellular
What is the main ion repsonsivle for generating a negative resting mebran potentia;?
K+
WHat is K+ regulated by where is it secreted? What is imabalnce triggered by?
regualted by kidney and secrited into the nephron for secretion?
Imbalance trigered by excedss K+ taken in or lsot or water imabalances
What is the nephron?
fucntional unit of kidney
what is high plasma K+ called? What does it do to resting membran of exciteable cells?
hyperkalemia - makes resting membrean of excieble cells more positive
what is lowplasma K+ called? What does it do to resting membran of exciteable cells?
hypokalemia - makes membrane of exciteable cells more negative
What two elctrolyetes are bound together in crystals?
CA2+ and Po43-
What is Po43- important for
prodicing atp molecules
what is calcium balance essential for?
uscle contractions, action potentials in the heart,
neuronal synaptic transmission, signaling inside all cells, blood clotting
What is high plasma ca2+ called? What does this do to cells
hypercalcemia - makes cells less permeable to Na+ = less excitable
What is low plasma ca2+ called? Whta does this do to cels
hypocalcemia - makes cells more permeable to Na+ = more exciteable
Is cl- higher in ecf or icf. Whats its role
ecf - creates osmotic gradient, forms HCl in stomach
Is mg hgiher in icf or ecf what is it critical for
ICF - critical for ceillar procsses - activating enzymes an fbone tissue
What should blood pH be?
7.35 – 7.45
What is the biggest source of metabolic acid? some others?
co2. Some others include lactic acis, uric acid and keton bodies
How else can acid abd bases be formed other than thru metabolism?
absorbed in IG tract
What acid and base can be removed from LUNGS AND KIDNEY?
ONLY CO2
What is the chemical buffering system in our body?
CO2 + H2O ↔ H2CO3 ↔ H+ + HCO3
what are 2 phsyological buffering systems in the body?
Respiratory system control the amount of CO2 (Fast-secponds)
renal system - kidnets can control the amount of all other acids and bases but takes more time (hours to days)
What is acidosis? What is the consequence?
Blood pH < 7.35
* Either too much CO2 or other acid for buffers to bind OR amount of buffer (e.g. HCO3-) is low
* Consequence: Neurons are less excitable (larger stimulus needed to initiate an action
potential
What is alkalosis? what is the consequence?
Blood pH > 7.45
* More base ions are added than buffers can handle, H+ concentration decreases / CO2 too
low
* Consequence: Neurons more excitable (action potentials are initiated when they shouldn’t
be)
What does Hypoventilation do to pH?
What condition is it associted with ____ acidosisis
What is it caused by?
how is it compenated
Respiratory acidosis
hypoventilation - increases co2 in blood - decreases pH = acidossis
supressed ventialtion due to breainstem dysfunction
Blcoked air passages in lungs
Decreased gas exxhange in alveoli
renal and respiratory compensation - probkem due to imoaired ventilation is fixed and PH s is restored as Co2 is expired (lungs)
RENAL: HCO3- reabsorbed int blood, increased h+ secreiton in urine, kidneys producenew HCO3-
-
What is metabloc acidsosis caused by?
How is it compensated fir?
Caused by too much H+ in blood or loss of Hco3- due to metablosm (ketoacidsis), diarrhea (loss of HCo3-, kidney failure, ingestion of acidic drugss or poison
comepensated by respiratory - hyepventialtion to reduce H+
Renal - if kidneys functioning properly - increased reabsorption of HCO3- back into blood and secretion of H+
What is respriatory vs metabolic acidosis?
respiratory is caused by increased Co2 in blood leading to decrease in PH and is to do with supressed ventialtion and breathing mechanisms like blcoked air passages, decreased gas excahnge
Metabloic is caused bytoo much H+ or decreased Hco3_ due to metabolism like kdinet failure, ingestion of drugs, diarhea
What is respiratory alakalosis?
respiratory and renal compensation?
increased blood pH due to low co2 - hyperventialtion caused by psychological response (anxiety) or physological respons (high altitude)
Resp compensation - hypoventialtion to restore co2 and increae H+ (decrease pH)
Renal. -excrete more HCo3- into urine and reabsorb more H+ back into blood
What is Metabolic alkalosis? How do the renal and respiratory systems compensate?
increased pH in blood due to loss of H+ or too much HCO3-
Respiratory - hypoventilation ot restore Co2 and icnrase H+ (decrease)
Renal - Increased reabsorption of H+ back into blood and secretion of HCO3- in
urine
What are the primary sex organs of males and females? what horomone does each secrete? What do they do
males - testes - testosterone
females - ovaries - esteogens
they produyce gametes (sex cells) via meiosis - sperm or oocytes
how many chromosomes does a gamete have?
Half of 46 = 23
What is the process of sperm development called and what is stimulated by?
spermatogenesis - testosterone
what type of hromone is testosterone? what type effects does it have? What is it released in response to
steroid - anabolic effects
LH - leutanizing hormone -
What does testosterone do at puberty? both priamry and secondary sex chacteristics
primary? growth, maturation and maintenace of male reproductive organs (testes, scrotum,..)
Development of secondary sex chracterisitc - pubic, faical hair, enlarged larync thichker vocal chords , sebaceous gland
what are the anabolic effects of testosterone? behavioural effects?
increased bone density, skeltal msucle mass. Libido - desrire for sexual acitvit
____ is released from the hypothalamus which stimulates ant pituitary to release______ and _____ which leads to testosterone and ABP production
Gonadotropin-Releasing Hormone (GnRH) LH and FSH
what does ABP do?
androgen binding protein binds to testosterone and stimualtes spermatogenesis
When do testosterone levels and spermatogensis decrease
at around 70
What are the 2 main funcitons of the ovaries?
produce oocytes - secrete hormones
what are the main 2 hormones secreted by the ovaries?
estrogens and progesterone
what is the process of oocyte development?
oogenesisi
what are the three main estrogens?
Estradiol
- Estrone
- Estrio
when does spermatogenesis begin>
at puberty till end of life
when does oogenesis begin?
before female is born and then paused until puberty
explain oogensis from puberty to menopause
1) once a month immature oocytes within individual follicles stimulated to develop
2) 1 oocyte continues to meiosis - released during ovulation
3a) either fertilized by sperm and matures into ovum (egg) chromosomes combine and cell division
3b) not fertalized and oocyte shed during menstruation
where is the oocyte matured?
within a follicle
what are the 3 main phases of the ovarian cycle? 28 day.
1) follicular
2) ovulation
3) luteal
What days is the follcicular, oculation and luteal phaseof the ovarian cycle?
Follicular. = day 1-13
ovulation = day 14
luteal = 15-28
what happens in follicular phase?
follcile grows and develops with oocyte inside
what happens during ovulation?
folllicle ruptures and releases maturing ooocyte and it is swept into the fallopian tube for journey into the uterus
what happens during luteal phase
left over ruptured follicle becomes the corpus luteum
the corpus lute secretes progesteron
- If pregnancy occurs. - corpus luteum stays for 3 months to produce progesterone
IF NO preganancy - corpus luteum degenerates in 10 days
during the luteal phase what happens to the leftover ruptured follicle?
corpus luteum
what is the corpus luteum and what does it secrete?
it is what the ruptured follicle becomes in the luteal phase and secretes progesterone
What does the LH do in the ovarian cycle?
stimulates follicle cells to secrete androgens
whhat does FSH stimulate during ovarian cycle?
conversion of androgens to estrogen and secretion of inhibin from follicle cells
what do follicle cells secrete?
inhibin
what do estrogens stimulate?
dominant follicle to mature, relay positive feedback to ant / pit to produce LH and FSH release which triggers ovulation
what triggers ovulation? what happens after/how is it inhibited?
Estrogen relays positive feedback to ant pit - LH and FSH released - trigger ovulation. INhibited when inhibin and estrogens relay negative feedback to hypothalmaus and ant. pit
During fertalization extended progesterone release from corpus luteum does what?
What about during NO fertaliztion?
continues to inhibit GnRH, LH, FSH release
No fertilization = corpus luteum degenerates - estrogen and progesterone levels drop - cycle starts again
what is the innermost lining of the uterus called/
endometrium
What happens to endometrium if no pregnancy?
detaches from uterine wall and is shed as a discharfe of blood with other fluid once a month (menstruation)
What are the 3 phases of the uterine cycle?
1) mentrual phase (day 1-5)
2) proliferative phase ( day 6-14)
3) secretory phase (day 15-28)
what happens to FSH and LH during menstrual phase? what happens to endmoetrium?
it begins to rise at day 1 - old layer is shed
what happens to FSH and LH during proliferative phase? what happens to layer?
it peaks at day 14 - estrogen levels rise
new layer develops and thickens
What happens to lining during secretory phase ? to hormones?
lining maintained to accomodate protential of fertilized egg
Progesterone rises, estrogen decreases and Lh and FSH are inhbiited
The secretory phase of the
uterine cycle corresponds
to the ____ phase of the
ovarian cycle.
luteal
what else does estrogen do?
Stimulate development of secondary sex characteristics
* External genitalia, breasts, fat accumulation around hips and thighs, pubic and axillary hair, increased
secretions of sebaceous glands
* Bone and skeletal muscle mass development (less potent than testosterone)
* Estrogens also exert a protective effect on the body
inhibit bone resorption (by inhibiting osteoclasts)
increased HDL level and decreased LDL level
general protective effect on the cardiovascular system
