MCAT Prep - 2

Instructions:

• Answer 50 questions in 15 minutes.
• If you are not ready to take this test, you can study here.
• Match each statement with the correct term.
• Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. microvilli: increase SA of enterocyte; have hi conc of digestive enzymes

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


2. Beta - oxidation in liver produces...
Mouth - esophagus - stomach - duodenum - jejunum - ileum - ascending colon - transverse colon - descending colon - sigmoid colon - rectum - anus
Facilitated diffusion from hi to lo conc
Ketone bodies; thus excessive reliance on fat for energy (eg low carb diets) results in ketosis; blood acidity increases
Inactive: rhodopsin is activated by photons; activated rhodopsin hyperpolarizes rod cells - causes photobleaching


3. Meiosis I Metaphase I
Fat synthesis; carbs stored as free fatty acids - esterified to TAGs (requires small amount of E)
Homologous chromosomes line up w/ attachment of spindle fibers/microtubule polymers to centromeres via kinetochores; identical in appearance under light microscope to metaphase of mitosis
Small intestine; duodenum is smallest and does most DIGESTION; jejunum is medium and does most ABSORPTION; ileum is biggest and does most absorption along with jejunum
Work together to emulsify fats: bile works as a detergent to increase SA of the fat; increased SA gives more substrate to lipase for digestion


4. Meiosis I Anaphase I
'visceral organs develop adjacent to a cavity and invaginate into the bag - like coelom'
Homologous chromosomes separate - migrate towards opposite poles/centrioles
Micelles; micelles (made of bile) go back and forth between brush border and chyme
Primitive streak - which consists of cells of the MESODERM ****


5. when thinking of proteins - think
Nitrogen
It targets liver conc of prothrombin - fibrinogen etc
Oxytocin and ADH (aka vasopressin)
Ammonia; must be converted to urea by liver and excreted in urine by kidney


6. Ovum development is halted At what stage until fertilization...
At metaphase II of meiosis II (halted during reductional division); if fertilized - process continues toward haploid gamete
Homologous chromosomes line up w/ attachment of spindle fibers/microtubule polymers to centromeres via kinetochores; identical in appearance under light microscope to metaphase of mitosis
Small intestine; duodenum is smallest and does most DIGESTION; jejunum is medium and does most ABSORPTION; ileum is biggest and does most absorption along with jejunum
Mouth - esophagus - stomach - duodenum - jejunum - ileum - ascending colon - transverse colon - descending colon - sigmoid colon - rectum - anus


7. bile + fat forms
(haploid organism) many fungi and protozoa; individuals are typically haploid; fertilization may occur with immediate meiosis back to haploid state
Adrenal gland -- AC: steroids (cortisol - aldosterone); AM: catecholamines (epi - norepi); Islets of langerhans: peptides (insulin/glucagon) ANTAGONISTS: calcitonin (thyroid - peptide lowers Ca in blood); parathyroid hormone - peptide - vitamin D pat
Faces the lumen
Micelles; micelles transport lipase products to enterocytes for absorption at brush border


8. small intestine=
Stomach - sm intest - spleen - pancreas from the hepatic portal vein...all blood that passes thru liver go thru flattened spaces called the ***hepatic sinusoids -->hepatic vein --->vena cava
Duodenum (wraps around pancreas; most digestion occurs here) - jejunum (pH 7-9; 2m) - ileum
Synthesizes lipids (including steroids); detoxifies drugs; is continuous with lumen
Comes into play in the large intestine - where vitamin b12 is absorbed w/help of E. coli; thus; must travel thru bloodstream to large intestine


9. Meiosis I Telophase I
Development of placenta begins with implantation; eventually - by end of first trimester - placenta will replace corpus luteum and its estrogen/progest secretions
sucrose (gluc+fruc) - lactose (gluc+galactose) - starch (gluc+gluc)
Nuclear envelope reassembled in daughter cells; cytokinesis occurs; nucleoli reappear (site of rRNA synthesis)
***nicotinic is ionotropic; muscarinic is GPCR


10. Human chorionic gonadotropin...
Glucose
Secreted by implanted egg; HCG prevents degeneration of the corpus luteum; HCG in blood/urine is first sign of pregnancy
5
On the chyme exiting the stomach and entering duodenum thru the pyloric sphincter


11. is intracellular AA conc hi or low?
Low because AAs are immediately used in translation
Determination is a pre - programmed fate - differentiation is the actual materialization of that fate
Result is proton secreted into lumen - bicarbonate into interstitial fluid (diffuses into blood); result is also increased blood pH and decreased pH stomach
Dehydration reaction; broken apart with enzyme - catalyzed hydrolysis


12. Path of urine

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


13. lysosome main function and derivation
Sorts - modifies - concentrates proteins from the ER
Ganglion
Contains hydrolytic enzymes; thus - digests endocytosed substances; derived from golgi
75% water/ 25% solid mass: of that solid mass: 10-20% fat = phospholipid bilayer of bacteria - slough - off enterocytes ie stomach lining (must be constantly rebuilt) 10-20% inorganic material 30% roughage = fiber = cellulose (indigestible) 2-3% prot


14. medium for paracrine hormones
Interstitial fluid (eg prostaglandins - cytokines)
**NO*** lipase digests fat; no bonds broken by bile; only opens up more SA for lipase
Pancreas; active at sm intestinal pH; hydrolyzes peptide bonds of (pepsin - digested) peptides
'The hepatic portal vein is not a true vein - because it does not conduct blood directly to the heart. It is a vessel in the abdominal cavity that drains blood from the gastrointestinal tract and spleen to capillary beds in the liver.'


15. Gastrin from G cells stims parietal cells...
Pepsin - secreted by chief cells in the stomach epithelial lining and active at low pH - breaks down proteins to polypeptides. Protein hydrolysis is aided by the highly acidic environment (hi gastric acid from parietal cells). Polypeptides are squirt
Tight regulation of parietal cells needed b/c gastric acid secretion is E- intensive; parietal cells are hi in mitochons
Homologous chromosomes separate - migrate towards opposite poles/centrioles
Follicular (proliferative)= 8d - Luteal (post - ovulation; corpus luteum secretions)= 13d - Menstruation (shed uterine lining if no implantation)= 5


16. In general - parietal=
Small amounts of hydrolyzed phospholipids and cholesterol: like other fat mols these can diffuse thru enterocyte membrane
Growth 1 (G1) phase: STRUCTURAL ProteinS - ENZYMES; This is a very active period - where the cell synthesizes its vast array of proteins - including the enzymes and structural proteins it will need for growth. In G1 stage each of the chromosomes cons
Secreted by delta cells of Islets of langerhans; inhibits insulin and glucagon; slows digestion
The wall of the body or of a body cavity or hollow structure


17. How is glucose absorbed in sm intest
Travels vas deferens - urethra; mixes with prostate fluids - seminal vesicles - couper's gland - etc
Regulated by gastrointestinal horms
Lots of water - minerals (electrolyte balance) - vitamins (aided by gut bacteria)
via symport - secondary transport (ie by pre - established - ATP- intensive) with Na gradient into enterocyte......with no Na gradient (ie without ATP) carbohydrate monomers could not be transported in


18. Inside the kidney: ...JGA (w/granular cells sensitive to hydrostatic pressure able to secrete renin - activate aldosterone - increase BP) is adjacent to distal tubule - monitors filtrate pressure
Pancreas; active at sm intestinal pH; hydrolyzes peptide bonds of (pepsin - digested) peptides
Water flows from the tubule - concentrating the filtrate - raising BP
Monitors filtrate pressure in the distal tubule; has specialized cells (granular cells) that secrete an enzyme (**renin); renin initiates regulatory cascade that produces angiotensin I - II - III that stim adrenal cortex to secrete aldosterone... ...
- filtration occurs at the fenestrations of the renal corpuscle - most reabsorption and secretion occur in the proximal tubule - medulla is concentrated in the loop of henle - sodium and calcium are reabsorbed in the distal tubule -->collecting tubul


19. what happens to bile secretions
Pancreas; active at sm intestinal pH; hydrolyzes peptide bonds of (pepsin - digested) peptides
Called a tract in the CNS; bundling together of axons/dendrites thru which many diff signals pass; many many neurons are bundled together into a single nerve
Posterior pituitary hormone; acts on uterus - mammary glands; causes uterine contractions - milk ejection
Mostly reabsorbed to liver


20. After meiosis I - daughter cells are...

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


21. Where does blood to be filtered by kidney enter the nephron?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


22. from the loop of henle...
Diarrhea: excess water loss in feces; poor absorption of vitamins - minerals
On to the distal tubule where sodium - calcium are reabsorbed - protons - bicarbonate - potassium are secreted via membrane transport proteins
Peptides
Within the paravertebral ganglion - running parallel to spinal cord


23. Tight junctions
Homologous chromosomes separate - migrate towards opposite poles/centrioles
Glands w/ducts: Exocrine glands
PH 6.0; this accomplished by pancreatic secretion of bicarbonate which ups pH
Form barrier to extracellular fluid


24. What is a dorsal root ganglion?
Glucose = aldose fructose = ketose
Increases blood Calcium
Collection of cell bodies; cell processes project out from both ends of ganglion; synapses with interneuron in spinal cord on one end and sensory receptor on other
(haploid organism) many fungi and protozoa; individuals are typically haploid; fertilization may occur with immediate meiosis back to haploid state


25. cytosol pH
Mouth - esophagus - stomach - duodenum - jejunum - ileum - ascending colon - transverse colon - descending colon - sigmoid colon - rectum - anus
Ectoderm: outer coverings - nervous system Mesoderm: between covering ie musc - bone - etc - endoderm: digestive tract - viscera
About 7.2
Diarrhea: excess water loss in feces; poor absorption of vitamins - minerals


26. FLAT PG: prolactin
Zygote (morula) composed of eight or more cells; All cells at this stage are TOTipOTENT STEM Cells: do not grow - form by cleavage
Cancer; apop can be programmed cell death; mitochon can play important role in apop
Peptide; prolactin promotes milk production; prolactin release is stimulated by act of suckling - which in turn inhibits menstrual cycle
Small intestine; duodenum is smallest and does most DIGESTION; jejunum is medium and does most ABSORPTION; ileum is biggest and does most absorption along with jejunum


27. components of interstitial fluid
PNS- Somatic - afferent (dorsal root ganglion) + efferent (ventral horns) PNS- ANS- afferent (sensors on viscera) + SYMP - PARA pre - post - ganglionic neurons
Glycosaminoglycans - prots - AAs - lipids
Two perpendicular semicircular canals involved in balance - equilibrium
Glucocorticoid (cortisol); mineralocorticoid (aldosterone)


28. Three stages of the menstrual cycle
Stims release of tyrosine - derived horms T3/T4 (increase basal metabolic rate); TSH increases thyroid cell size - number - rate of T3/T4 synth -----> thus - iodine deficiency causes swollen thyroid due to lack of neg feedback onto TSH in anterior pi
Inactive: rhodopsin is activated by photons; activated rhodopsin hyperpolarizes rod cells - causes photobleaching
Follicular (proliferative)= 8d - Luteal (post - ovulation; corpus luteum secretions)= 13d - Menstruation (shed uterine lining if no implantation)= 5
Epithelial tissue near semniferous tubules


29. Posterior pituitary hormones (Small Peptides)
(haploid organism) many fungi and protozoa; individuals are typically haploid; fertilization may occur with immediate meiosis back to haploid state
Fat synthesis; carbs stored as free fatty acids - esterified to TAGs (requires small amount of E)
Ammonia; must be converted to urea by liver and excreted in urine by kidney
Oxytocin and ADH (aka vasopressin)


30. almost all cells can store Some glycogen - but...
Only musc and esp ** liver can store large amounts
Faces the lumen
Digestion
visual (rhodopsin is receptor - derived from Vit A; conformation change occurs with photon to hyperpolarize rod cells; cone cells use photopsin for receptor) - olfactory - mood (NTs targeted by antidepressants - antipsychotics - etc; GABA is inhibit


31. food in duod stims release of gastrointestinal hormones
In mouth - breakdown of starch into polysaccharides
From lumenal (apical) to enterocyte to basolateral side of epithelial tissue
Secreted by implanted egg; HCG prevents degeneration of the corpus luteum; HCG in blood/urine is first sign of pregnancy
Gall bladder - pancreatic secretions increase - arrive via ampulla of vater (duct glands); insulin secretion increases (fed state; ductless glands)


32. What is the pH at the entrance to the duodenum
Alpha 1-4 and 1-6 (branching) glycosidic linkages
Glands w/ducts: Exocrine glands
Salivary amylase; both hydrolyze glycosidic linkages
PH 6.0; this accomplished by pancreatic secretion of bicarbonate which ups pH


33. Does bile digest fat?
Conjunction of cell body w/axon
Formed in kidney (nephron) - sent thru renal pelvis - down ureter to bladder - drained by urethra'
Prophase II: no crossing over b/c there are no homologous chromosomes; nuclear envelope dissolves Metaphase II: chromosomes line up at metaphase plate Anaphase II: sister chromatids separate - migrate to opp poles Telophase II: nuclear envelope reap
**NO*** lipase digests fat; no bonds broken by bile; only opens up more SA for lipase


34. mitosis creates somatic cells
Ups bicarbonate secretion by pancreas; raises pH to 6.0
Amino acid monomers - di - tri absorbed by symport at enterocyte; each AA has slightly diff mechanism; from entero - AAs enter bloodstream where they are taken up by all cells of the body - esp the liver by active or facilitated transport (NEVER PASS
Hydrostatic pressure forces some plasma thru *fenestrations of the glomerular endothelium* and into Bowman's capsule; B.C. is continuous with lumen of nephron
Meiosis creates germ cells


35. Cell bodies of SYMP postganglionic neurons lie far from effector...
Within the paravertebral ganglion - running parallel to spinal cord
- enterocytes w/ *microvilli brush border*: membrane - bound digestive enzymes for carbs - fats - nucleic acids - goblet cells: secrete mucous - Deep between villi are the intestinal exocrine glands - the crypts of Lieberkuhn - which secrete pH 7.6 i
Peptide; stims growth of nearly all cell of body; all other anterior pituitary horms have specific targets; upregulates anabolic pathways; use of fat for energy goes up (fat - burning); increases AA transport across cell membrane (nutrient uptake)
Fructose is a structural isomer of glucose


36. 'Cell bodies of somatic motor neurons are located in....'
Liposome has phospholipid bilayer
Spinal cord ventral horns; somatic motor neurons use acetylcholine for NTs (voluntary)
Estradiol
Urine enters kidneys via artery - to arteriole - capillary bed - glomerulus - Bowman's capsule - proximal tubule - loop of henle (concentrates medulla) - distal tubule - collecting tubule - collecting duct (renal pyramids) - renal calyx - renal pelvi


37. In other words...
Food is digested from mouth to stomach (denaturation by gastric acid - digested by pepsin) to duodenum (more digestion); then absorption occurs in jejunum and ileum
Development of placenta begins with implantation; eventually - by end of first trimester - placenta will replace corpus luteum and its estrogen/progest secretions
Secrete intrinsic factor; important for absorbing vitamin B12 in sm intest
Smaller - more water soluble short - chain FAs go directly to bloodstream at villi capillaries


38. ADH
Nuclear envelope reassembled in daughter cells; cytokinesis occurs; nucleoli reappear (site of rRNA synthesis)
Hormones --->stimulate exocrine glands - acetylcholine (increases all secretion of gastric pits) - gastrin (from G cells) - histamine (increases HCl secretion of parietals) ...Ach increases all secretions; gastrin increases gastric acid (parietal cel
Raises BP; causes collecting ducts at end of nephron (kidney) to become permeable to water - which concentrates urine; coffee - beer block ADH and increase urine volume
Comes into play in the large intestine - where vitamin b12 is absorbed w/help of E. coli; thus; must travel thru bloodstream to large intestine


39. Where does the juxtaglomerular apparatus come into play...renin --->inc angiotensins -->inc aldosterone - ups BP
Monitors filtrate pressure in the distal tubule; has specialized cells (granular cells) that secrete an enzyme (**renin); renin initiates regulatory cascade that produces angiotensin I - II - III that stim adrenal cortex to secrete aldosterone... ...
Carbohydrates are highly hydrated: one water mol per carbon mol - fats are anhydrous: contain more reduced carbons per unit mass - altogether fats contain 6X energy per unit mass
Nervous - muscle - epithelial (defines inner/outer) - connective (extensive matrices)
Sensory neurons are affector; motor neurons are effector // dorsal afferent (dorsal - Back- side of spinal cord carries sensory signals to brain; ventral effector


40. pancreatic enzymes are zymogens
Sensory (afferent - dorsal) - motor (efferent - ventral)
Calcitonin (peptide; lowers blood Ca); T3/T4 (tyrosine - derived; increase basal metabolic rate); T4= thyroxine
From lumenal (apical) to enterocyte to basolateral side of epithelial tissue
Trypsinogen is activated by enterokinase in the brush border; in turn - it activates other enzymes


41. calcitonin

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183


42. sensory (afferent) neurons
Receive signals from receptor cell w/ ability to interact with its environment; 99% sensory input is discarded
(diploid and haploid individuals = ALTERNATION of GENERATIONS) a fusion of gametic and zygotic life cycles
cornea (1.4 refractory index; bends light) - pupil (size of pupil is determined by contraction state of the iris) - aqueous humor
Moves down thru esophageal sphincter


43. What is gastric acid?
HCl; secreted by parietal cells under stim by gastrin
An endogenous morphine
It targets liver conc of prothrombin - fibrinogen etc
TAGS--->FFAs; remember that FFAs are broken down for energy in mito matrix by beta - oxidation


44. What is somatostatin
Growth 1 (G1) phase: STRUCTURAL ProteinS - ENZYMES; This is a very active period - where the cell synthesizes its vast array of proteins - including the enzymes and structural proteins it will need for growth. In G1 stage each of the chromosomes cons
Secreted by delta cells of Islets of langerhans; inhibits insulin and glucagon; slows digestion
Result: stress reaction; increase glycogenolysis - gluconeogenesis; fat/prot breakdown; increase blood glucose
Nourishes follicle growth; stimulates granulosa cell growth around primary oocyte at puberty = primary follicle; also - stimulates Sertoli cells in males


45. main point of fat transport...
Visceral layer= parietal layer; serous membrane is the container of the coelom/peritoneal cavity
Fat is insoluble in blood and requires a carrier like lipoproteins (vLDL...HDL) or albumins; ...vLDL has hi triglycerides - hi cholesterol
The crypts of Lieberkuhn: sm intestine pH is not right; brush border enzs won't work right
Meiosis creates germ cells


46. What does peroxisome do
vitreous humor - retina - fovea
Oxidizes macromolecules; breaks down very long - chain FAs by beta - oxidation; products (acetyl - CoA) are shuttled to mitochondrion for citric acid cycle
Adrenal gland -- AC: steroids (cortisol - aldosterone); AM: catecholamines (epi - norepi); Islets of langerhans: peptides (insulin/glucagon) ANTAGONISTS: calcitonin (thyroid - peptide lowers Ca in blood); parathyroid hormone - peptide - vitamin D pat
Transfer signals from neuron - neuron; 90% of neurons are interneurons


47. examples of different cavities... (compartments for viscera)
Low because AAs are immediately used in translation
pericardial cavity - pleural cavity (contains lungs) - peritoneal cavity (abdominal)
Steroid; target tissue is distal convoluted tubule of nephron and collecting duct; increases blood mineral concentration; potassium - protons secreted (blood pH increases); sodium - chloride reabsorbed (BP increases)
Food is digested from mouth to stomach (denaturation by gastric acid - digested by pepsin) to duodenum (more digestion); then absorption occurs in jejunum and ileum


48. ligands are the messenger compounds that target secondary messenger systems on effectors
Smooth ER
Many modern drugs are ligands for GPCRs
Mostly reabsorbed to liver
Systems (eg digestive system consists of many organs)


49. testosterone can be aromatized to...
Estradiol
Ammonia; must be converted to urea by liver and excreted in urine by kidney
Notochord (mesoderm) induces ectoderm to thicken into neural plate --->neural tube --->spinal cord
Fovea (highest amount of cones)


50. position of AP...
PH 6.0; this accomplished by pancreatic secretion of bicarbonate which ups pH
Faces the lumen
Below hypothalamus
Stims release of tyrosine - derived horms T3/T4 (increase basal metabolic rate); TSH increases thyroid cell size - number - rate of T3/T4 synth -----> thus - iodine deficiency causes swollen thyroid due to lack of neg feedback onto TSH in anterior pi