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MCAT Prep - 2

Subjects : mcat, science

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. Mucus - digestive enzymes released thru
Which is why lactase - maltase - dextrinase - sucrase are on brush border
Outer ear= pinna (auricle)- external auditory canal - eardrum (tympanic membrane) inner ear= malleus - incus - stapes - ...oval window - cochlea - where sound is transduced into neural signal...enters cochlea at scala vestibuli - where pressure chang
Glands w/ducts: Exocrine glands
Diarrhea: excess water loss in feces; poor absorption of vitamins - minerals

2. A pinpoint iris is contracted or uncontracted
TAGS--->FFAs; remember that FFAs are broken down for energy in mito matrix by beta - oxidation
Uncontracted: parasymp (eg opoid use)
Sympathetic: dilates pupil (for night hunting)
Gastric inhibitory pep; increase of pancreatic - enz activating enzymes (which cleaves zymogens like trypsinogen); increased gall bladder contraction; decreases stomach mobility

3. FLAT PG: prolactin
Peptide; prolactin promotes milk production; prolactin release is stimulated by act of suckling - which in turn inhibits menstrual cycle
Adrenocorticotropin; stims adrenal cortex release of glucocorticoids (eg cortisol - a steroid) stress hormones via second messenger system using cAMP
Meiosis creates germ cells
Formed in kidney (nephron) - sent thru renal pelvis - down ureter to bladder - drained by urethra'

4. Blastocyst
Testosterone upon stim by LH
After 4 day+ - morula cells have formed fluid - filled ball (blastocyst); this implants in uterus at day 5-7; blastocyst is made up of EMBRYONIC STEM Cells; once implanted w/blastocyst - female is pregnant
Membrane - bound - endocytosed bodies
Beta cells

5. E storage per unit mass
It is the animal counterpart of starch; it is more highly- branched - thus releases more glucose monomers upon repeated hydrolysis than starch
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
Abdominal cavity - which is coated in serous fluid
Peristalsis (esophagus) and segmentation (bi - directional=mixing)

6. How does duod deal with hi HCl from stom
Combined via conjunction of pancreatic duct and common bile duct; common bile duct originates at **cystic duct where gall bladder and liver secretions combine ..cystic duct+common bile duct+pancreatic duct --->into duodenum
Ups bicarbonate secretion by pancreas; raises pH to 6.0
Conjunction of cell body w/axon
Facilitated diffusion: no symport w/ secondary transport

7. Fructose relates how structurally to glucose
Glucose
Fructose is a structural isomer of glucose
Liver breaks down glycogen (glycogenolysis); at hi blood sugar it builds up glycogen (glycogenesis)
Increases blood Calcium

8. almost all exocytosed proteins pass through this
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... ...
Smooth ER
Going up - water - impermeable: salt is actively pumped out - filtrate osmolarity goes down as salt leaves
Outermost layer of blood vessel

9. Cell determination begins At what stage of development
After morula - with blastocyst (+8 cell count)--->totipotent to embryonic stem cell and so on
Receive signals from receptor cell w/ ability to interact with its environment; 99% sensory input is discarded
RBCs - large proteins; What does enter is called the filtrate
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

10. important pancreatic enzymes
Trypsin(- ogen; activates other panc enzymes after it is activated by enterokinase of sm intest); chymotrypsin - amylase - lipase
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
Peristalsis (esophagus) and segmentation (bi - directional=mixing)
AAs enter bloodstream for uptake by all cells (esp liver). If intracellular prot conc is at max AAs can be converted to fats or glucose via gluconeogenesis. Byproduct of gluconeo is ammonia --->urea.

11. Peritoneal refers to...
Abdominal cavity - which is coated in serous fluid
Trypsin(- ogen; activates other panc enzymes after it is activated by enterokinase of sm intest); chymotrypsin - amylase - lipase
In liver (RBC recycling of heme); stored in gall bladder; released via cystic duct to common bile duct (shared w/liver); common bile duct joins up with panc duct...everything feeds into the sm intest at the ampulla of vater**
Fat synthesis; carbs stored as free fatty acids - esterified to TAGs (requires small amount of E)

12. spermatogonia arise from
90-140 mg/dl
Nitrogen
Epithelial tissue near semniferous tubules
Alpha cells; stims gluconeogenesis in liver; acts via cAMP second messenger

13. What is the path of a sound wave that enters the ear?
Outer ear= pinna (auricle)- external auditory canal - eardrum (tympanic membrane) inner ear= malleus - incus - stapes - ...oval window - cochlea - where sound is transduced into neural signal...enters cochlea at scala vestibuli - where pressure chang
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
PH 6.0; this accomplished by pancreatic secretion of bicarbonate which ups pH
The renal corpuscle

14. Morula (...totipotent)
Receive signals from receptor cell w/ ability to interact with its environment; 99% sensory input is discarded
Result: stress reaction; increase glycogenolysis - gluconeogenesis; fat/prot breakdown; increase blood glucose
Ventrally (picture skeletal vertebrae)
Zygote (morula) composed of eight or more cells; All cells at this stage are TOTipOTENT STEM Cells: do not grow - form by cleavage

15. Glucose is a .... sugar; fructose is a .... sugar
'visceral organs develop adjacent to a cavity and invaginate into the bag - like coelom'
It is the animal counterpart of starch; it is more highly- branched - thus releases more glucose monomers upon repeated hydrolysis than starch
Glucose = aldose fructose = ketose
Via secondary active transport proteins (COSTS E TO FILTER BLOOD - ESTABLISH FLUID/ION BALANCE)

16. examples of different cavities... (compartments for viscera)
All carbs absorbed at enterocytes are carried to liver by portal vein
AAs enter bloodstream for uptake by all cells (esp liver). If intracellular prot conc is at max AAs can be converted to fats or glucose via gluconeogenesis. Byproduct of gluconeo is ammonia --->urea.
Presence of fat - prot in duodenum causes release of **gastric inhibitory peptide**; result is slower stomach contraction; slower emptying into duod thru pyloric sphincter (slower chyme secretion); more time to properly digest - absorb nutrients
pericardial cavity - pleural cavity (contains lungs) - peritoneal cavity (abdominal)

17. when thinking of proteins - think
Primitive streak - which consists of cells of the MESODERM ****
Spinal cord ventral horns; somatic motor neurons use acetylcholine for NTs (voluntary)
Nitrogen
Micelles; micelles transport lipase products to enterocytes for absorption at brush border

18. sporic life cycle
Hypothalamus --->AP--->target tissues eg TSH - thyroid - T3/T4 release - increase basal metabolic rate
Below hypothalamus
cornea (1.4 refractory index; bends light) - pupil (size of pupil is determined by contraction state of the iris) - aqueous humor
(diploid and haploid individuals = ALTERNATION of GENERATIONS) a fusion of gametic and zygotic life cycles

19. SYMP neurons originate in= PARA neurons originate in=
Via secondary active transport proteins (COSTS E TO FILTER BLOOD - ESTABLISH FLUID/ION BALANCE)
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
Hydrostatic pressure forces some plasma thru *fenestrations of the glomerular endothelium* and into Bowman's capsule; B.C. is continuous with lumen of nephron
Injury that does not sever SC (causes deep lesion from back - front) might cause loss of feeling without full loss of motion

20. What does peptic refer to in general
'tones the bone'; decreases free Calcium conc; acts opposite to parathyroid hormone; thyroid polypeptide
Result is proton secreted into lumen - bicarbonate into interstitial fluid (diffuses into blood); result is also increased blood pH and decreased pH stomach
Digestion
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

21. What (typically - ie not pre - ovulation) feeds back to decrease LH - FSH production?
Contain capillary network - lymph vessels (lacteals)
It targets liver conc of prothrombin - fibrinogen etc
Testosterone and estradiol
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

22. Embryology
An endogenous morphine
Zygote - morula (first four days) - blastocyst (4 day+; implants in uterine lining) - gastrula (2 week) - neurula (3 week)...
Via secondary active transport proteins (COSTS E TO FILTER BLOOD - ESTABLISH FLUID/ION BALANCE)
Tight regulation of parietal cells needed b/c gastric acid secretion is E- intensive; parietal cells are hi in mitochons

23. Kidney
Ventrally (picture skeletal vertebrae)
Excretes waste products: urea - uric acid - ammonia - phosphate - maintains homeostasis: including body fluid volume (water reabsorption) and solute composition (mineral balance - nutrient reabsorption) - controls *plasma* pH: antiport of Na/K and pr
(diploid and haploid individuals = ALTERNATION of GENERATIONS) a fusion of gametic and zygotic life cycles
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

24. Examples of GPCRs in sensory systems/signal transduction: What is the ligand or messenger in each case? ...SIGHT - SMELL - MOOD - FIGHT/FLIGHT etc
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
Photon (hv)- rhodopsin - conformation change - GPCR- Na less permeable - hyperpolarized rod cells - generates AP= photobleaching at visible light wavelengths (390-700nm)
Protein digestion begins in stomach; low pH denatures proteins - kills bacteria; mixes - stores food and destroys it to chyme (BOLUS-->CHYME)
Glucose = aldose fructose = ketose

25. What are the major carbohydrates
Secreted by implanted egg; HCG prevents degeneration of the corpus luteum; HCG in blood/urine is first sign of pregnancy
Notochord (mesoderm) induces ectoderm to thicken into neural plate --->neural tube --->spinal cord
Buildup of macromolecules in lysosome due to deficient lysosome enzymes
sucrose (gluc+fruc) - lactose (gluc+galactose) - starch (gluc+gluc)

26. In general - parietal=
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
The wall of the body or of a body cavity or hollow structure
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)
Formed in kidney (nephron) - sent thru renal pelvis - down ureter to bladder - drained by urethra'

27. Meiosis II: EQUATIONAL DIVISION
An ether phospholipid; hi conc in myelin; thus - hi conc in heart tiss - nervous tiss
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
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
After morula - with blastocyst (+8 cell count)--->totipotent to embryonic stem cell and so on

28. euk cell has two principal sides
Lumen (ie continuous w/body cavity) and cytosol
Cancer; apop can be programmed cell death; mitochon can play important role in apop
Needs time for bile - lipase - micelle migration - enterocyte uptake
Epithelial tissue near semniferous tubules

29. bile + fat forms
Sensory (afferent - dorsal) - motor (efferent - ventral)
Neurons may perform one of three functions....
Micelles; micelles transport lipase products to enterocytes for absorption at brush border
Travels vas deferens - urethra; mixes with prostate fluids - seminal vesicles - couper's gland - etc

30. components of interstitial fluid
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)
Testes>Semeniferous tubules>Sertoli cells; feedback on AP FSH production
Glycosaminoglycans - prots - AAs - lipids
Changes: volume of filtrate does not change: osmolarity of filtrate --->reabsorbed ions like sodium carry water across membrane

31. gradual increase in FSH typical of primary follicle development;
Oxytocin and ADH (aka vasopressin)
Secondary follicle: Theca cells differentiate from interstitial tissue - surround follicle - secrete testosterone when stimd by LH (compare to Leydig cells)
TAGS--->FFAs; remember that FFAs are broken down for energy in mito matrix by beta - oxidation
Within the paravertebral ganglion - running parallel to spinal cord

32. What do the glomerulus and Bowman's capsule add up to...
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
The renal corpuscle
Moves down thru esophageal sphincter
Receive signals from receptor cell w/ ability to interact with its environment; 99% sensory input is discarded

33. During meiosis I and II in females - rather than creating four chromosomally- equivalent gametes...
Mouth - esophagus - stomach - duodenum - jejunum - ileum - ascending colon - transverse colon - descending colon - sigmoid colon - rectum - anus
Secondary follicle: Theca cells differentiate from interstitial tissue - surround follicle - secrete testosterone when stimd by LH (compare to Leydig cells)
An endogenous morphine
Creates one ovum (23 N) and three polar bodies

34. serous membranes have a viscera - facing layer and a body wall - facing layer
Visceral layer= parietal layer; serous membrane is the container of the coelom/peritoneal cavity
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
Pancreatic duct (made of acinar cells?)
Nuclear envelope reassembled in daughter cells; cytokinesis occurs; nucleoli reappear (site of rRNA synthesis)

35. position of AP...
Somatic sensory = dorsal root ganglia (outside spinal cord); somatic effector = ventral horns of spinal cord
Below hypothalamus
Glycosaminoglycans - prots - AAs - lipids
Peak at 1-2hr after meal; chylomicrons themselves have half - life of about 1hr after formation in enterocytes

36. portal vein physiology...

37. What do lipases do
Creates one ovum (23 N) and three polar bodies
Can be saturated; conc of a solute is called the transport maximum --->excess goes into urine
cornea (1.4 refractory index; bends light) - pupil (size of pupil is determined by contraction state of the iris) - aqueous humor
Break down TAGs to monoglycerides and free fatty acids

38. So - following blastocyst implantation (4d) - at approx 2 weeks past fertilization
Gastrulation occurs: formation of three primary germ layers = differentiation
Vitamin K - b12 - thiamin - riboflavin
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
Outer ear= pinna (auricle)- external auditory canal - eardrum (tympanic membrane) inner ear= malleus - incus - stapes - ...oval window - cochlea - where sound is transduced into neural signal...enters cochlea at scala vestibuli - where pressure chang

39. What is a nerve? (PNS)
Lysosome
Conjunction of cell body w/axon
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
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

40. Where do absorbed fats go in the enterocyte
Glucose
To the organelle w/ lumen: smooth ER; they are resynthesized into TAGs
Sudiferous (sweat) - sebaceous - digestive (bile - pancreatic enzs) - mucosal
Estrogen: steroid; stims LH in luteal surge; causes growth of female sex organs progesterone: prepares/maintains uterus for pregnancy

41. How does reabsorption force nutrients across apical membrane of proximal tubule
(diploid and haploid individuals = ALTERNATION of GENERATIONS) a fusion of gametic and zygotic life cycles
- parietal cells (**oxyntic= hi oxygen consumption - hi E??): have hi conc mito; need lots of energy to create proton gradient; thus - responsible for extremely harsh pH conditions in stom; denaturing conditions - chief cells (peptic): synthesize pep
Oxytocin and ADH (aka vasopressin)
Via secondary active transport proteins (COSTS E TO FILTER BLOOD - ESTABLISH FLUID/ION BALANCE)

42. What does lipase attack exactly
Peak at 1-2hr after meal; chylomicrons themselves have half - life of about 1hr after formation in enterocytes
TAGS--->FFAs; remember that FFAs are broken down for energy in mito matrix by beta - oxidation
- parietal cells (**oxyntic= hi oxygen consumption - hi E??): have hi conc mito; need lots of energy to create proton gradient; thus - responsible for extremely harsh pH conditions in stom; denaturing conditions - chief cells (peptic): synthesize pep
Salivary amylase (weak); sm intest amylase (breaks down large polysaccharides)

43. amylase acts where on carbs
Secrete intrinsic factor; important for absorbing vitamin B12 in sm intest
Salivary amylase (weak); sm intest amylase (breaks down large polysaccharides)
Four 23 N daughter cells are formed from one 46 2N mother (germ - line) cell; four haploid gametes
Inner lining of circulatory system

44. How is the follicle developed during oogenesis
Micelles; micelles transport lipase products to enterocytes for absorption at brush border
Formed in kidney (nephron) - sent thru renal pelvis - down ureter to bladder - drained by urethra'
Arrested at primary oocyte; hypothalamus GnRH->FSH released at puberty stims granulosa cell development; granulosa secrete zona pellucida = primary follicle
Hypothalamus --->AP--->target tissues eg TSH - thyroid - T3/T4 release - increase basal metabolic rate

45. Leydig cells produce
Outer ear= pinna (auricle)- external auditory canal - eardrum (tympanic membrane) inner ear= malleus - incus - stapes - ...oval window - cochlea - where sound is transduced into neural signal...enters cochlea at scala vestibuli - where pressure chang
Going up - water - impermeable: salt is actively pumped out - filtrate osmolarity goes down as salt leaves
Testosterone upon stim by LH
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

46. lining of abdominal cavity=
Peripheral nervous sys
- parietal cells (**oxyntic= hi oxygen consumption - hi E??): have hi conc mito; need lots of energy to create proton gradient; thus - responsible for extremely harsh pH conditions in stom; denaturing conditions - chief cells (peptic): synthesize pep
Determined by whether in front of or behind the lens
Serous membrane (slick - reducing friction) that forms lining of the coelom --> secretes lubricating fluid

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

48. trypsin is secreted by
Peripheral nervous sys
Transfer signals from neuron - neuron; 90% of neurons are interneurons
Primitive streak - which consists of cells of the MESODERM ****
Pancreas; active at sm intestinal pH; hydrolyzes peptide bonds of (pepsin - digested) peptides

49. What is the function of the loop of Henle
Fructose is a structural isomer of glucose
Increases solute conc and osmotic pressure of the ***medulla
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
Salivary amylase; both hydrolyze glycosidic linkages

50. Meiosis I: REDUCTIONAL DIVISION Interphase: G1 (growth; enzymes - structural proteins needed for gametic production are synthesized); S (DNA of homologous chromosomes is duplicated; mother cell goes from 46 2N to 46 2N with sister chromosomes connect
**NO*** lipase digests fat; no bonds broken by bile; only opens up more SA for lipase
Zygote - morula (first four days) - blastocyst (4 day+; implants in uterine lining) - gastrula (2 week) - neurula (3 week)...
Prophase I: crossing over occurs; nuclear envelope is absorbed into ER; chromosomes condense)
Via secondary active transport proteins (COSTS E TO FILTER BLOOD - ESTABLISH FLUID/ION BALANCE)