Test your basic knowledge |

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. What does lipase attack exactly
Inactive: rhodopsin is activated by photons; activated rhodopsin hyperpolarizes rod cells - causes photobleaching
Sudiferous (sweat) - sebaceous - digestive (bile - pancreatic enzs) - mucosal
TAGS--->FFAs; remember that FFAs are broken down for energy in mito matrix by beta - oxidation
90-140 mg/dl

2. During ejaculation - sperm...

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

3. How is the follicle developed during oogenesis
90-140 mg/dl
Di - tri - peptides; inside enterocytes are hydrolyzed to amino acids
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
Arrested at primary oocyte; hypothalamus GnRH->FSH released at puberty stims granulosa cell development; granulosa secrete zona pellucida = primary follicle

4. How does the body mobilize fat stores
Corpus luteum degrades into corpus albicans
Pancreas; active at sm intestinal pH; hydrolyzes peptide bonds of (pepsin - digested) peptides
Di - tri - peptides; inside enterocytes are hydrolyzed to amino acids
***starting with adipose tiss: FFAs are transported in the blood by albumin (major component of blood plasma); one albumin typically carries three fatty acid molecules but can hold up to 30 FAs

5. little by little chyme is squirted out thru pyloric sphincter
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
Regulated by gastrointestinal horms
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
Glands w/ducts: Exocrine glands

6. How does water cross the apical membrane
Thru tight junctions by favorable osmotic gradient
**NO*** lipase digests fat; no bonds broken by bile; only opens up more SA for lipase
An ether phospholipid; hi conc in myelin; thus - hi conc in heart tiss - nervous tiss
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

7. How long are peptides when absorbed at brush border
Di - tri - peptides; inside enterocytes are hydrolyzed to amino acids
Glycosaminoglycans - prots - AAs - lipids
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
Interstitial fluid (eg prostaglandins - cytokines)

8. Gastrulation: ectoderm/mesoderm/endoderm
Epithelial tissue near semniferous tubules
Posterior pituitary hormone; acts on uterus - mammary glands; causes uterine contractions - milk ejection
Ectoderm: outer coverings - nervous system Mesoderm: between covering ie musc - bone - etc - endoderm: digestive tract - viscera
Within the paravertebral ganglion - running parallel to spinal cord

9. pancreas secretes enzymes via
Interstitial fluid (eg prostaglandins - cytokines)
Paracrine (local) - endocrine (longer distance)
Pancreatic duct (made of acinar cells?)
Estradiol (estrogen - steroid horm); prepares uterine wall for pregnancy; just before ovulation - release of estradiol stims LH in pos feedback

10. What force is acting upon chyme to move it forward down sm intestine
Micelles; micelles transport lipase products to enterocytes for absorption at brush border
Peristalsis (esophagus) and segmentation (bi - directional=mixing)
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
Posterior pituitary hormone; acts on uterus - mammary glands; causes uterine contractions - milk ejection

11. fructose enters enterocyte by
Corpus luteum degrades into corpus albicans
Facilitated diffusion: no symport w/ secondary transport
= catecholamines; fight/flight; vasoconstrictors of internal organs - skin; vasodilators of skel musc; also considered stress hormones; epinephrine - norepinephrine
Lumen (ie continuous w/body cavity) and cytosol

12. signal transduction occurs only in
Eukaryotes
Neurons may perform one of three functions....
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
Interstitial fluid (eg prostaglandins - cytokines)

13. 3 phases of menstrual cycle
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
Follicular phase: primary - secondary - ovulation (1 week) luteal phase: ovulation - thickening of uterine lining w/corpus luteum secretion - corpus luteum degrades (2 weeks) flow: shedding of uterine lining (4 days)
Eg spinal nerve - cranial nerve; Not All Nervous Tissue In Brain - SC Is CNS Tissue
Secreted by delta cells of Islets of langerhans; inhibits insulin and glucagon; slows digestion

14. protein absorption at enterocyte
Neurons may perform one of three functions....
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
Size of fist; two kidneys; have cortex (steroid hormones) and medulla (catecholamines) - receives about 20% of cardiac output - blood travels down arteries - up veins -'urine is created by the kidney and emptied into the renal pelvis - which is empti
In gastric pits; secretions combine into gastric juice

15. hypothalamus - AP - ACTH - cortisol release from adrenal cortex
Diarrhea: excess water loss in feces; poor absorption of vitamins - minerals
Glycosaminoglycans - prots - AAs - lipids
Has memb - bound organelles - etc...
Result: stress reaction; increase glycogenolysis - gluconeogenesis; fat/prot breakdown; increase blood glucose

16. Adrenal cortex hormones (STEROIDS)
Uncontracted: parasymp (eg opoid use)
Know that 90% digestion - absorption occurs in sm intestine --> fine breakdown of carbs - fat - prots
Glucocorticoid (cortisol); mineralocorticoid (aldosterone)
Glucose

17. Different organs working together
Gastrulation occurs: formation of three primary germ layers = differentiation
Mouth - esophagus - stomach - duodenum - jejunum - ileum - ascending colon - transverse colon - descending colon - sigmoid colon - rectum - anus
Systems (eg digestive system consists of many organs)
Reconstituted into TAGs at smooth ER; first stop for most digested fat is liver

18. Where would materials slated for digestion go?
Beta cells
Di - tri - peptides; inside enterocytes are hydrolyzed to amino acids
Eg spinal nerve - cranial nerve; Not All Nervous Tissue In Brain - SC Is CNS Tissue
Lysosome

19. How does birth control work?
'Increased absorptive area is useful because digested nutrients (including sugars and amino acids) pass into the villi through diffusion - which is effective only at short distances. In other words - **increased surface area (in contact with the flui
Transfer signals from neuron - neuron; 90% of neurons are interneurons
Lumen (ie continuous w/body cavity) and cytosol
Maintains hi estrogen levels; body does not recognize luteal surge - ovulation does not occur; hi progesterone can lessen shedding by thickening the uterine lining

20. Blastocyst
Chylomicrons are much bigger
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
Beta cells
Glands w/ducts: Exocrine glands

21. The esophageal sphincter is...
Normally contracted
Injury that does not sever SC (causes deep lesion from back - front) might cause loss of feeling without full loss of motion
Protein digestion begins in stomach; low pH denatures proteins - kills bacteria; mixes - stores food and destroys it to chyme (BOLUS-->CHYME)
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

22. Spinal cord horns (thick knobs) point
On the chyme exiting the stomach and entering duodenum thru the pyloric sphincter
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
Number of centromeres - Not number of chromatids eg - two sister chromatids connected by one centromere = one chromosome
Ventrally (picture skeletal vertebrae)

23. Aldosterone (sodium uptake - potassium secretion)
Mostly reabsorbed to liver
Trypsinogen is activated by enterokinase in the brush border; in turn - it activates other enzymes
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)
Prophase I: crossing over occurs; nuclear envelope is absorbed into ER; chromosomes condense)

24. Alpha - amylase found where
In mouth - breakdown of starch into polysaccharides
90-140 mg/dl
Determined by whether in front of or behind the lens
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

25. What determines number of chromosomes?
Travels vas deferens - urethra; mixes with prostate fluids - seminal vesicles - couper's gland - etc
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
Somatic nervous sys - autonomic nervous sys
Number of centromeres - Not number of chromatids eg - two sister chromatids connected by one centromere = one chromosome

26. Between meals most fats appear in blood as
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
Moves down thru esophageal sphincter
23 N; 23 chromosomes and haploid (no homologous chromosomes); each chromosome has two sister chromatids Male: primary spermatocyte -->REDUCTIONAL DIVISION (first stim'd at puberty by GnRH - LH-->secondary spermatocyte Female: primary oocyte (arreste
Lipoproteins; albumin carries free fatty acids when fat is mobilized from adipose tissue - etc

27. only monosaccharides are absorbed
Gastrulation occurs: formation of three primary germ layers = differentiation
Which is why lactase - maltase - dextrinase - sucrase are on brush border
(diploid organism) humans are part of gametic life cycle ie produce gametes; diploid germ - line stem cells undergo meiosis to form haploid gametes
Cancer; apop can be programmed cell death; mitochon can play important role in apop

28. Where does fertilization occur
Fallopian tubes
It is the animal counterpart of starch; it is more highly- branched - thus releases more glucose monomers upon repeated hydrolysis than starch
Form barrier to extracellular fluid
Mostly reabsorbed to liver

29. How is glucose absorbed in sm intest
PH 6.0; this accomplished by pancreatic secretion of bicarbonate which ups pH
Facilitated diffusion from hi to lo conc
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
Peristalsis (esophagus) and segmentation (bi - directional=mixing)

30. portal vein physiology...

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

31. peroxisome is derived from this
ER
Increases blood Calcium
It targets liver conc of prothrombin - fibrinogen etc
Liver breaks down glycogen (glycogenolysis); at hi blood sugar it builds up glycogen (glycogenesis)

32. 'Cell bodies of somatic motor neurons are located in....'
Salivary amylase; both hydrolyze glycosidic linkages
Increase surface area of sm intestine; this improves digestion (enzymes adsorbed to villi) and absorption
Conjunction of cell body w/axon
Spinal cord ventral horns; somatic motor neurons use acetylcholine for NTs (voluntary)

33. Which fats are not absorbed like this
Changes: volume of filtrate does not change: osmolarity of filtrate --->reabsorbed ions like sodium carry water across membrane
Smaller - more water soluble short - chain FAs go directly to bloodstream at villi capillaries
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
Inner lining of circulatory system

34. What is secreted into filtrate by cells of the proximal tubule?
Drugs - toxins - bile pigments (color the urine) - uric acid - antibiotics
Micelles; micelles transport lipase products to enterocytes for absorption at brush border
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
Prod of steroid hormones in testes - ovaries

35. gametic life cycle
(diploid organism) humans are part of gametic life cycle ie produce gametes; diploid germ - line stem cells undergo meiosis to form haploid gametes
Epithelial tissue near semniferous tubules
Eukaryotes
Synthesizes lipids (including steroids); detoxifies drugs; is continuous with lumen

36. light detection via GPCRs
The crypts of Lieberkuhn: sm intestine pH is not right; brush border enzs won't work right
The wall of the body or of a body cavity or hollow structure
Photon (hv)- rhodopsin - conformation change - GPCR- Na less permeable - hyperpolarized rod cells - generates AP= photobleaching at visible light wavelengths (390-700nm)
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

37. How do monoglycerides and ffas get to brush border?
Small amounts of hydrolyzed phospholipids and cholesterol: like other fat mols these can diffuse thru enterocyte membrane
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
Micelles; micelles (made of bile) go back and forth between brush border and chyme
'Microvilli function as the **primary surface of nutrient absorption in the gastrointestinal tract**. Because of this vital function - the microvillar membrane is packed with enzymes that aid in the breakdown of complex nutrients into simpler compoun

38. oxytocin
Posterior pituitary hormone; acts on uterus - mammary glands; causes uterine contractions - milk ejection
Visceral layer= parietal layer; serous membrane is the container of the coelom/peritoneal cavity
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
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

39. when cells hit their limit for prot storage...
Water flows from the tubule - concentrating the filtrate - raising BP
Digestion
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
AAs can be burned for energy or converted to fat for storage

40. in the presence of ADH what happens to movement of water across nephron membr
Low because AAs are immediately used in translation
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
Water flows from the tubule - concentrating the filtrate - raising BP
Result: stress reaction; increase glycogenolysis - gluconeogenesis; fat/prot breakdown; increase blood glucose

41. at lo blood sugar...
Direction of differentiation
Determined by whether in front of or behind the lens
Oxytocin and ADH (aka vasopressin)
Liver breaks down glycogen (glycogenolysis); at hi blood sugar it builds up glycogen (glycogenesis)

42. alpha - amylase in the mouth digests what kind of bond
Protein digestion begins in stomach; low pH denatures proteins - kills bacteria; mixes - stores food and destroys it to chyme (BOLUS-->CHYME)
Somatic sensory = dorsal root ganglia (outside spinal cord); somatic effector = ventral horns of spinal cord
Alpha 1-4 and 1-6 (branching) glycosidic linkages
vitreous humor - retina - fovea

43. Neuronal cell bodies have extensions ie
Thru tight junctions by favorable osmotic gradient
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
Processes: axons - dendrites
Cancer; apop can be programmed cell death; mitochon can play important role in apop

44. keep in mind that enterocyte is like a regular euk cell
Processes: axons - dendrites
Determination is a pre - programmed fate - differentiation is the actual materialization of that fate
Has memb - bound organelles - etc...
Result: stress reaction; increase glycogenolysis - gluconeogenesis; fat/prot breakdown; increase blood glucose

45. lining of abdominal cavity=
'tones the bone'; decreases free Calcium conc; acts opposite to parathyroid hormone; thyroid polypeptide
Direction of differentiation
Drugs - toxins - bile pigments (color the urine) - uric acid - antibiotics
Serous membrane (slick - reducing friction) that forms lining of the coelom --> secretes lubricating fluid

46. What testosterone released by secondary follicle by LH stim is converted to...
Estradiol (estrogen - steroid horm); prepares uterine wall for pregnancy; just before ovulation - release of estradiol stims LH in pos feedback
ER
At the collecting duct: becomes more permeable to water which passively diffuses *into the medulla* concentrating the urine
Peptides

47. when thinking of proteins - think
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
Trypsin(- ogen; activates other panc enzymes after it is activated by enterokinase of sm intest); chymotrypsin - amylase - lipase
Nitrogen
Outermost layer of blood vessel

48. Where do pancreatic secretions take effect
Fat synthesis; carbs stored as free fatty acids - esterified to TAGs (requires small amount of E)
Renal pyramids --->renal calyx-->renal pelvis -->ureter -->urethra
On the chyme exiting the stomach and entering duodenum thru the pyloric sphincter
Alpha 1-4 and 1-6 (branching) glycosidic linkages

49. When 'coumadin targets liver enzymes to act as anticoagulant'...
It targets liver conc of prothrombin - fibrinogen etc
In mouth - breakdown of starch into polysaccharides
Systems (eg digestive system consists of many organs)
Within the paravertebral ganglion - running parallel to spinal cord

50. What does peptic refer to in general
Digestion
Most absorption occurs in sm intestine
Lumen (ie continuous w/body cavity) and cytosol
An endogenous morphine