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. Cell bodies of SYMP postganglionic neurons lie far from effector...
Changes: volume of filtrate does not change: osmolarity of filtrate --->reabsorbed ions like sodium carry water across membrane
Within the paravertebral ganglion - running parallel to spinal cord
Meiosis creates germ cells
Eukaryotes


2. Local vs long - distance mediators
Estradiol (estrogen - steroid horm); prepares uterine wall for pregnancy; just before ovulation - release of estradiol stims LH in pos feedback
Paracrine (local) - endocrine (longer distance)
Increases blood Calcium
CARB- Digesting: dextrinase (polysachs produced by hydrolysis of starch) - maltase (glucose - glucose) - sucrase (glucose - fructose) - lactase (galactose - glucose) - Protein- Digesting: peptidases - NUCLEOTIDE- Digesting: nucleosidases


3. What if large intestine isn't working well
Diarrhea: excess water loss in feces; poor absorption of vitamins - minerals
cornea (1.4 refractory index; bends light) - pupil (size of pupil is determined by contraction state of the iris) - aqueous humor
Regulated by gastrointestinal horms
**only para effectors have muscarinic receptors; symp effectors are adrenergic (epi - norepi); **neuromuscular junction uses nicotinic receptors


4. mucus cells line the stomach...
Liver Functions pt. 2 - Carb metabolism: blood is sent straight to liver from sm intest thru portal vein; liver is control center for blood glucose; _______________ - fat metabolism: oxidizes fat for energy by beta - oxidation - forms most lipoprotei
Contain rough ER and Golgi to make mucous; mucous is full of **glycoprots (sticky) and electrolytes*; protects epithelial tiss of stomach from low pH and lubricates stomach
Signal picked up by sensory cell - goes thru dorsal root ganglion to SC - may continue to interneurons in brain or simple reflex arc in SC - brain integrates info and decides (voluntary) response - travels back down SC to appropriate ventral root gan
Lens will be rounded; contraction of the lens (ie focusing) is done by ciliary muscle


5. Energy from fat - prot - gluc
FAT=9 cal per gram Carbs=4.5 cal per gram - Prot=4 cal per gram - these seem to be for anhydrous forms
Diarrhea: excess water loss in feces; poor absorption of vitamins - minerals
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
Estrogen: steroid; stims LH in luteal surge; causes growth of female sex organs progesterone: prepares/maintains uterus for pregnancy


6. So - following blastocyst implantation (4d) - at approx 2 weeks past fertilization
Gastrulation occurs: formation of three primary germ layers = differentiation
SYMP: spinal cord --->paravetebral ganglion PARA: spinal cord - brain; cell processes --->ganglion near effector organ (preganglionic neurons) extend outside of spinal cord to synapse at ganglia - go on along postganglionic neurons
Estradiol
It targets liver conc of prothrombin - fibrinogen etc


7. from the loop of henle...
On to the distal tubule where sodium - calcium are reabsorbed - protons - bicarbonate - potassium are secreted via membrane transport proteins
(diploid organism) humans are part of gametic life cycle ie produce gametes; diploid germ - line stem cells undergo meiosis to form haploid gametes
Meiosis creates germ cells
Secreted by delta cells of Islets of langerhans; inhibits insulin and glucagon; slows digestion


8. food in duod stims release of gastrointestinal hormones
Gall bladder - pancreatic secretions increase - arrive via ampulla of vater (duct glands); insulin secretion increases (fed state; ductless glands)
Spinal cord ventral horns; somatic motor neurons use acetylcholine for NTs (voluntary)
Dehydration reaction; broken apart with enzyme - catalyzed hydrolysis
Increases blood Calcium


9. lining of abdominal cavity=
Serous membrane (slick - reducing friction) that forms lining of the coelom --> secretes lubricating fluid
Peptides
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
Fat is insoluble in blood and requires a carrier like lipoproteins (vLDL...HDL) or albumins; ...vLDL has hi triglycerides - hi cholesterol


10. FLAT PG: ACTH
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
Adrenocorticotropin; stims adrenal cortex release of glucocorticoids (eg cortisol - a steroid) stress hormones via second messenger system using cAMP
Maintains hi estrogen levels; body does not recognize luteal surge - ovulation does not occur; hi progesterone can lessen shedding by thickening the uterine lining
Peptide; responsible for luteal surge (driven in part by LH-->testosterone -->estradiol -->LH positive feedback); results in ovulation (follicle bursting) - releasing egg into fallopian tube/oviduct


11. How does reabsorption force nutrients across apical membrane of proximal tubule
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
Know that 90% digestion - absorption occurs in sm intestine --> fine breakdown of carbs - fat - prots
Via secondary active transport proteins (COSTS E TO FILTER BLOOD - ESTABLISH FLUID/ION BALANCE)
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


12. exocrine types
Sudiferous (sweat) - sebaceous - digestive (bile - pancreatic enzs) - mucosal
Result is proton secreted into lumen - bicarbonate into interstitial fluid (diffuses into blood); result is also increased blood pH and decreased pH stomach
- 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
Gonadotropin releasing hormone - GnRH


13. PNS review: SAME DAVE
The wall of the body or of a body cavity or hollow structure
Ectoderm: outer coverings - nervous system Mesoderm: between covering ie musc - bone - etc - endoderm: digestive tract - viscera
Lowers osmolarity of the filtrate (IONS - Water Are Taken Back Up By The Kidney)--->at the end of the distal tubule (the collecting tubule) is where aldosterone acts - along with the JGA
Sensory neurons are affector; motor neurons are effector // dorsal afferent (dorsal - Back- side of spinal cord carries sensory signals to brain; ventral effector


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

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


15. How do parietal cells work ** (involves CO2)
Glands w/ducts: Exocrine glands
Development of placenta begins with implantation; eventually - by end of first trimester - placenta will replace corpus luteum and its estrogen/progest secretions
Within the paravertebral ganglion - running parallel to spinal cord
Result is proton secreted into lumen - bicarbonate into interstitial fluid (diffuses into blood); result is also increased blood pH and decreased pH stomach


16. 80% of end product of carbohydrate metabolism is...
Glucose
Testosterone and estradiol
At the collecting duct: becomes more permeable to water which passively diffuses *into the medulla* concentrating the urine
PNS- Somatic - afferent (dorsal root ganglion) + efferent (ventral horns) PNS- ANS- afferent (sensors on viscera) + SYMP - PARA pre - post - ganglionic neurons


17. Adrenal cortex hormones (STEROIDS)
Inner lining of circulatory system
Sympathetic: dilates pupil (for night hunting)
Glucocorticoid (cortisol); mineralocorticoid (aldosterone)
pericardial cavity - pleural cavity (contains lungs) - peritoneal cavity (abdominal)


18. The path from blood plasma to urine

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


19. The apical side of the villi...
Going up - water - impermeable: salt is actively pumped out - filtrate osmolarity goes down as salt leaves
Faces the lumen
Increases surface area of food ball (bolus)
(diploid and haploid individuals = ALTERNATION of GENERATIONS) a fusion of gametic and zygotic life cycles


20. Ovum development is halted At what stage until fertilization...
Estradiol
Corpus luteum; secretes estradiol - progesterone throughout pregnancy OR if no pregnancy - for about 2 weeks (till menstruation = shedding of uterine lining)
At metaphase II of meiosis II (halted during reductional division); if fertilized - process continues toward haploid gamete
Alpha 1-4 and 1-6 (branching) glycosidic linkages


21. How does birth control work?
Ventrally (picture skeletal vertebrae)
Maintains hi estrogen levels; body does not recognize luteal surge - ovulation does not occur; hi progesterone can lessen shedding by thickening the uterine lining
Lower blood pH
After morula - with blastocyst (+8 cell count)--->totipotent to embryonic stem cell and so on


22. bile + fat forms
Stom= G cells (gastrin) - parietal (oxyntic); chief (peptic); mucous cells (hi ER - Golgi to make sticky glycoprots) - sm intest= enterocytes (w/brush border of maltase - sucrase - lactase - dextrinase; peptidase; lipase; nucleases); goblet cells (mu
Micelles; micelles transport lipase products to enterocytes for absorption at brush border
**only para effectors have muscarinic receptors; symp effectors are adrenergic (epi - norepi); **neuromuscular junction uses nicotinic receptors
Secrete intrinsic factor; important for absorbing vitamin B12 in sm intest


23. How does blood sugar move into tissues?
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
Going up - water - impermeable: salt is actively pumped out - filtrate osmolarity goes down as salt leaves
Facilitated diffusion from hi to lo conc
Interneurons working to integrate signals received from the peripheral nervous system (sense organs)


24. albumin has What affect on blood osmotic pressure
Oxidizes macromolecules; breaks down very long - chain FAs by beta - oxidation; products (acetyl - CoA) are shuttled to mitochondrion for citric acid cycle
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
Albumin increases osmolarity of blood; increases osmotic pressure
Mediate complex cell processes thru eg phosphorylation via secondary messenger (G protein) systems = signal transduction pathway - GPCR (G protein coupled receptor)


25. What hormones affect the stomach?
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
Signal picked up by sensory cell - goes thru dorsal root ganglion to SC - may continue to interneurons in brain or simple reflex arc in SC - brain integrates info and decides (voluntary) response - travels back down SC to appropriate ventral root gan
Nervous - muscle - epithelial (defines inner/outer) - connective (extensive matrices)
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


26. What is the net effect of the loop of Henle
AAs can be burned for energy or converted to fat for storage
REABSORPTION: draws off water and ions - increases osmolarity of the medulla while slightly lowering osmolarity of the filtrate -->medulla must have hi osmolarity in order to concentrate urine at collecting duct (final step in nephron)
Testosterone upon stim by LH
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


27. light detection via GPCRs
Zygote (fertilization in fallopian tubes); morula (up to 8 cells - undifferentiated ie totipotent); blastocyst (4+ days - implants into uterus; HCG secretion stims corpus luteum; gradually placenta replaces HCG as estrogen/progest source; cells not t
Eg spinal nerve - cranial nerve; Not All Nervous Tissue In Brain - SC Is CNS Tissue
Only musc and esp ** liver can store large amounts
Photon (hv)- rhodopsin - conformation change - GPCR- Na less permeable - hyperpolarized rod cells - generates AP= photobleaching at visible light wavelengths (390-700nm)


28. Spinal cord horns (thick knobs) point
Ventrally (picture skeletal vertebrae)
Hydrostatic pressure forces some plasma thru *fenestrations of the glomerular endothelium* and into Bowman's capsule; B.C. is continuous with lumen of nephron
Needs time for bile - lipase - micelle migration - enterocyte uptake
***nicotinic is ionotropic; muscarinic is GPCR


29. in the presence of ADH what happens to movement of water across nephron membr
Fat is insoluble in blood and requires a carrier like lipoproteins (vLDL...HDL) or albumins; ...vLDL has hi triglycerides - hi cholesterol
Water flows from the tubule - concentrating the filtrate - raising BP
Increases solute conc and osmotic pressure of the ***medulla
Contain capillary network - lymph vessels (lacteals)


30. portal vein physiology...

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


31. What does lipase attack exactly
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
TAGS--->FFAs; remember that FFAs are broken down for energy in mito matrix by beta - oxidation
Notochord (mesoderm) induces ectoderm to thicken into neural plate --->neural tube --->spinal cord
Fructose is a structural isomer of glucose


32. Polypeptides are formed with what kind of reaction?
Dehydration reaction; broken apart with enzyme - catalyzed hydrolysis
Somatic sensory = dorsal root ganglia (outside spinal cord); somatic effector = ventral horns of spinal cord
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
Ammonia; must be converted to urea by liver and excreted in urine by kidney


33. What surrounds the hydrophilic heads of the new TAGs
Apoproteins attach to outside of globules; these move to Golgi and are released into interstitial fluid via exocytosis as chylomicrons --->most go to lacteal system
Estradiol
Secondary oocyte (stim'd by LH stimulation of theca cells causing release of testosterone - converted to estradiol; eventually brings about luteal surge -->EQUATIONAL DIVISION-->ovum released during ovulation into fallopian tube; burst follicle becom
Facilitated diffusion from hi to lo conc


34. parathyroid hormones
Nourishes follicle growth; stimulates granulosa cell growth around primary oocyte at puberty = primary follicle; also - stimulates Sertoli cells in males
Prod of steroid hormones in testes - ovaries
Chylomicrons are much bigger
Parathyroid hormone (peptide; increases blood Ca); thus - might increase osteoclast/decrease osteoblast activity


35. Stomach has no lacteals
Many modern drugs are ligands for GPCRs
Most absorption occurs in sm intestine
Testes>Semeniferous tubules>Sertoli cells; feedback on AP FSH production
Prophase I: crossing over occurs; nuclear envelope is absorbed into ER; chromosomes condense)


36. oxytocin
Serous membrane (slick - reducing friction) that forms lining of the coelom --> secretes lubricating fluid
Note: enteric= small intestine - double layer of peritoneum that suspends jejunum/ileum from posterior abdominal wall = connective tissue
CARB- Digesting: dextrinase (polysachs produced by hydrolysis of starch) - maltase (glucose - glucose) - sucrase (glucose - fructose) - lactase (galactose - glucose) - Protein- Digesting: peptidases - NUCLEOTIDE- Digesting: nucleosidases
Posterior pituitary hormone; acts on uterus - mammary glands; causes uterine contractions - milk ejection


37. On what surface of the retina is the eye most sensitive
Fovea (highest amount of cones)
Contain rough ER and Golgi to make mucous; mucous is full of **glycoprots (sticky) and electrolytes*; protects epithelial tiss of stomach from low pH and lubricates stomach
Lower blood pH
SYMP: spinal cord --->paravetebral ganglion PARA: spinal cord - brain; cell processes --->ganglion near effector organ (preganglionic neurons) extend outside of spinal cord to synapse at ganglia - go on along postganglionic neurons


38. what happens to bile secretions
Mostly reabsorbed to liver
Sensory neurons are affector; motor neurons are effector // dorsal afferent (dorsal - Back- side of spinal cord carries sensory signals to brain; ventral effector
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
Pancreas; active at sm intestinal pH; hydrolyzes peptide bonds of (pepsin - digested) peptides


39. Sensory neuron cell bodies vs. somatic motor cell bodies
Cancer; apop can be programmed cell death; mitochon can play important role in apop
Inner lining of blood vessels
Night vision
Somatic sensory = dorsal root ganglia (outside spinal cord); somatic effector = ventral horns of spinal cord


40. quote on cavities/viscera

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


41. Morula (...totipotent)
Normally contracted
Zygote (morula) composed of eight or more cells; All cells at this stage are TOTipOTENT STEM Cells: do not grow - form by cleavage
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
Lots of energy; eg neurons have hi glucose need for 3Na out 2K in ATPase; stomach epithel tiss needs E for parietal cells to pump protons into lumen and bicarbonate into blood


42. Examples of GPCRs in sensory systems/signal transduction: What is the ligand or messenger in each case? ...SIGHT - SMELL - MOOD - FIGHT/FLIGHT etc
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
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
Notochord (mesoderm) induces ectoderm to thicken into neural plate --->neural tube --->spinal cord
- 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


43. Posterior pituitary hormones (Small Peptides)
Prod of steroid hormones in testes - ovaries
Salivary amylase (weak); sm intest amylase (breaks down large polysaccharides)
Oxytocin and ADH (aka vasopressin)
Fallopian tubes


44. Kidney physiology...

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


45. What is the adventitia?
RBCs - large proteins; What does enter is called the filtrate
Outermost layer of blood vessel
Four 23 N daughter cells are formed from one 46 2N mother (germ - line) cell; four haploid gametes
Renal pyramids --->renal calyx-->renal pelvis -->ureter -->urethra


46. Leydig cells produce
Within the paravertebral ganglion - running parallel to spinal cord
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
PNS- Somatic - afferent (dorsal root ganglion) + efferent (ventral horns) PNS- ANS- afferent (sensors on viscera) + SYMP - PARA pre - post - ganglionic neurons
Testosterone upon stim by LH


47. What is a dorsal root ganglion?
Development of placenta begins with implantation; eventually - by end of first trimester - placenta will replace corpus luteum and its estrogen/progest secretions
Glycosaminoglycans - prots - AAs - lipids
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
Direction of differentiation


48. After meiosis II...
Glands w/ducts: Exocrine glands
Testosterone and estradiol
Four 23 N daughter cells are formed from one 46 2N mother (germ - line) cell; four haploid gametes
Contain capillary network - lymph vessels (lacteals)


49. What do lipases do
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
Break down TAGs to monoglycerides and free fatty acids
Contains lysozyme - which regulates bacteria within intestine; breaks down peptidoglycans (**bact wall); innate immunity
Micelles; micelles transport lipase products to enterocytes for absorption at brush border


50. For focal point that is nearby - what will the lens look like
Lens will be rounded; contraction of the lens (ie focusing) is done by ciliary muscle
Chylomicrons are much bigger
Duodenum (wraps around pancreas; most digestion occurs here) - jejunum (pH 7-9; 2m) - ileum
In mouth - breakdown of starch into polysaccharides