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 is main difference is signal transmission in nicotinic vs muscarinic?
**NO*** lipase digests fat; no bonds broken by bile; only opens up more SA for lipase
***nicotinic is ionotropic; muscarinic is GPCR
Liver breaks down glycogen (glycogenolysis); at hi blood sugar it builds up glycogen (glycogenesis)
Transfer signals from neuron - neuron; 90% of neurons are interneurons

2. Where else does ADH act
Bacterial flagellin: hollow filament (not microtub); euk: 9+2 microtubule w/dynein bridges
At the collecting duct: becomes more permeable to water which passively diffuses *into the medulla* concentrating the urine
Secreted by delta cells of Islets of langerhans; inhibits insulin and glucagon; slows digestion
Micelles; micelles transport lipase products to enterocytes for absorption at brush border

3. spermatogonia arise from
***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
Zygotes are diploid
Epithelial tissue near semniferous tubules
Glucose

4. golgi body
Sorts - modifies - concentrates proteins from the ER
Increase surface area of sm intestine; this improves digestion (enzymes adsorbed to villi) and absorption
HCl; secreted by parietal cells under stim by gastrin
Nourishes follicle growth; stimulates granulosa cell growth around primary oocyte at puberty = primary follicle; also - stimulates Sertoli cells in males

5. sensory (afferent)/interneurons/motor (efferent)
Lens will be rounded; contraction of the lens (ie focusing) is done by ciliary muscle
Hydrostatic pressure forces some plasma thru *fenestrations of the glomerular endothelium* and into Bowman's capsule; B.C. is continuous with lumen of nephron
Where lipoprotein lipase hydrolyzes TAGs; products diffuse into target tiss (mostly liver - adipose tissue)
Neurons may perform one of three functions....

6. Peritoneal refers to...
Abdominal cavity - which is coated in serous fluid
Gonadotropin releasing hormone - GnRH
Most absorption occurs in sm intestine
Which is why lactase - maltase - dextrinase - sucrase are on brush border

7. Anatomy of the villi
Note: enteric= small intestine - double layer of peritoneum that suspends jejunum/ileum from posterior abdominal wall = connective tissue
Increase surface area of sm intestine; this improves digestion (enzymes adsorbed to villi) and absorption
Ketone bodies; thus excessive reliance on fat for energy (eg low carb diets) results in ketosis; blood acidity increases
Contain capillary network - lymph vessels (lacteals)

8. micelles vs liposomes
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
Via secondary active transport proteins (COSTS E TO FILTER BLOOD - ESTABLISH FLUID/ION BALANCE)
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)
Liposome has phospholipid bilayer

9. How does the body mobilize fat stores
***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
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)
Direction of differentiation
Prod of steroid hormones in testes - ovaries

10. serous membranes have a viscera - facing layer and a body wall - facing layer
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
Vitamin K - b12 - thiamin - riboflavin
Visceral layer= parietal layer; serous membrane is the container of the coelom/peritoneal cavity
Result: stress reaction; increase glycogenolysis - gluconeogenesis; fat/prot breakdown; increase blood glucose

11. Anterior eye
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
Direction of differentiation
cornea (1.4 refractory index; bends light) - pupil (size of pupil is determined by contraction state of the iris) - aqueous humor
Prod of steroid hormones in testes - ovaries

12. What are phagosomes
HCl; secreted by parietal cells under stim by gastrin
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
Interstitial fluid (eg prostaglandins - cytokines)
Membrane - bound - endocytosed bodies

13. What is gastric acid?
HCl; secreted by parietal cells under stim by gastrin
'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
Sorts - modifies - concentrates proteins from the ER
Normally contracted

14. How do monoglycerides and ffas get to brush border?
Prod of steroid hormones in testes - ovaries
Paracrine (local) - endocrine (longer distance)
Zygote (morula) composed of eight or more cells; All cells at this stage are TOTipOTENT STEM Cells: do not grow - form by cleavage
Micelles; micelles (made of bile) go back and forth between brush border and chyme

15. What kind of cells make up epithel tiss of stom - then sm intest?
1) by integral ion channels 2) transmitted by second messenger system
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
= catecholamines; fight/flight; vasoconstrictors of internal organs - skin; vasodilators of skel musc; also considered stress hormones; epinephrine - norepinephrine
Primitive streak - which consists of cells of the MESODERM ****

16. What is the net effect of the loop of Henle
Thru tight junctions by favorable osmotic gradient
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
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)
Arrested at primary oocyte; hypothalamus GnRH->FSH released at puberty stims granulosa cell development; granulosa secrete zona pellucida = primary follicle

17. parathyroid hormones
- 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
Parathyroid hormone (peptide; increases blood Ca); thus - might increase osteoclast/decrease osteoblast activity
Albumin increases osmolarity of blood; increases osmotic pressure
Fat is insoluble in blood and requires a carrier like lipoproteins (vLDL...HDL) or albumins; ...vLDL has hi triglycerides - hi cholesterol

18. PNS nerve signal
Contains hydrolytic enzymes; thus - digests endocytosed substances; derived from golgi
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
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
Somatic sensory = dorsal root ganglia (outside spinal cord); somatic effector = ventral horns of spinal cord

19. What does portal vein do
Peptide; prolactin promotes milk production; prolactin release is stimulated by act of suckling - which in turn inhibits menstrual cycle
All carbs absorbed at enterocytes are carried to liver by portal vein
Night vision
At the collecting duct: becomes more permeable to water which passively diffuses *into the medulla* concentrating the urine

20. How is glucose absorbed in sm intest
Gastric inhibitory pep; increase of pancreatic - enz activating enzymes (which cleaves zymogens like trypsinogen); increased gall bladder contraction; decreases stomach mobility
Calcitonin (peptide; lowers blood Ca); T3/T4 (tyrosine - derived; increase basal metabolic rate); T4= thyroxine
Peak at 1-2hr after meal; chylomicrons themselves have half - life of about 1hr after formation in enterocytes
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

21. A contracted iris occurs with what kind of stimulation
Membrane - bound - endocytosed bodies
= catecholamines; fight/flight; vasoconstrictors of internal organs - skin; vasodilators of skel musc; also considered stress hormones; epinephrine - norepinephrine
Contain capillary network - lymph vessels (lacteals)
Sympathetic: dilates pupil (for night hunting)

22. FLAT PG: LH
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
Sudiferous (sweat) - sebaceous - digestive (bile - pancreatic enzs) - mucosal
AAs can be burned for energy or converted to fat for storage
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)

23. Spinal cord horns (thick knobs) point
Travels vas deferens - urethra; mixes with prostate fluids - seminal vesicles - couper's gland - etc
Paracrine (local) - endocrine (longer distance)
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
Ventrally (picture skeletal vertebrae)

24. 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

25. After meiosis II - Female

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

26. zygotic life cycle
Lower blood pH
(haploid organism) many fungi and protozoa; individuals are typically haploid; fertilization may occur with immediate meiosis back to haploid state
'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
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

27. liver receives blood from...
It is the animal counterpart of starch; it is more highly- branched - thus releases more glucose monomers upon repeated hydrolysis than starch
- 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
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
Inner lining of blood vessels

28. trypsin is secreted by
Epithelial tissue near semniferous tubules
Pancreas; active at sm intestinal pH; hydrolyzes peptide bonds of (pepsin - digested) peptides
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
Oxidizes macromolecules; breaks down very long - chain FAs by beta - oxidation; products (acetyl - CoA) are shuttled to mitochondrion for citric acid cycle

29. During ejaculation - sperm...

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

30. Thus - central nervous sys is...
Interneurons working to integrate signals received from the peripheral nervous system (sense organs)
= catecholamines; fight/flight; vasoconstrictors of internal organs - skin; vasodilators of skel musc; also considered stress hormones; epinephrine - norepinephrine
An endogenous morphine
AAs can be burned for energy or converted to fat for storage

31. Creating gradients requires what?
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
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
Sensory (afferent - dorsal) - motor (efferent - ventral)
Lens will be rounded; contraction of the lens (ie focusing) is done by ciliary muscle

32. Mucus - digestive enzymes released thru
Form barrier to extracellular fluid
Glands w/ducts: Exocrine glands
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
Serous membrane (slick - reducing friction) that forms lining of the coelom --> secretes lubricating fluid

33. large intestine E. coli aid absorption of...
Regulated by gastrointestinal horms
Follicular (proliferative)= 8d - Luteal (post - ovulation; corpus luteum secretions)= 13d - Menstruation (shed uterine lining if no implantation)= 5
Fat synthesis; carbs stored as free fatty acids - esterified to TAGs (requires small amount of E)
Vitamin K - b12 - thiamin - riboflavin

34. Does bile digest fat?
**NO*** lipase digests fat; no bonds broken by bile; only opens up more SA for lipase
Corpus luteum; secretes estradiol - progesterone throughout pregnancy OR if no pregnancy - for about 2 weeks (till menstruation = shedding of uterine lining)
Testosterone upon stim by LH
Moves down thru esophageal sphincter

35. Kidney
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
Somatic nervous sys - autonomic nervous sys
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
Uncontracted: parasymp (eg opoid use)

36. PNS is broken down into
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
Ventrally (picture skeletal vertebrae)
Glands w/ducts: Exocrine glands
Somatic nervous sys - autonomic nervous sys

37. Morula (...totipotent)
Protein digestion begins in stomach; low pH denatures proteins - kills bacteria; mixes - stores food and destroys it to chyme (BOLUS-->CHYME)
Lipoproteins; albumin carries free fatty acids when fat is mobilized from adipose tissue - etc
Zygote (morula) composed of eight or more cells; All cells at this stage are TOTipOTENT STEM Cells: do not grow - form by cleavage
Below hypothalamus

38. What is the function of the loop of Henle
Oxytocin and ADH (aka vasopressin)
Increases solute conc and osmotic pressure of the ***medulla
Zygote (morula) composed of eight or more cells; All cells at this stage are TOTipOTENT STEM Cells: do not grow - form by cleavage
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

39. What does lipase attack exactly
TAGS--->FFAs; remember that FFAs are broken down for energy in mito matrix by beta - oxidation
**NO*** lipase digests fat; no bonds broken by bile; only opens up more SA for lipase
Gall bladder - pancreatic secretions increase - arrive via ampulla of vater (duct glands); insulin secretion increases (fed state; ductless glands)
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

40. duodenum must have receptors for fat content - protein because
Fallopian tubes
Increases solute conc and osmotic pressure of the ***medulla
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... ...
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

41. A pinpoint iris is contracted or uncontracted
Corpus luteum degrades into corpus albicans
Dehydration reaction; broken apart with enzyme - catalyzed hydrolysis
Uncontracted: parasymp (eg opoid use)
Micelles; micelles (made of bile) go back and forth between brush border and chyme

42. What if large intestine isn't working well
The renal corpuscle
Creates one ovum (23 N) and three polar bodies
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
Diarrhea: excess water loss in feces; poor absorption of vitamins - minerals

43. liver and blood glucose...
Peristalsis (esophagus) and segmentation (bi - directional=mixing)
5
Liver is the control center for blood glucose; is fed by portal vein from sm intest
- 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

44. Both divisions (somatic - autonomic) of PNS consist of...
Sensory (afferent - dorsal) - motor (efferent - ventral)
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
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
Sudiferous (sweat) - sebaceous - digestive (bile - pancreatic enzs) - mucosal

45. Blastocyst
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
Outermost layer of blood vessel
Digestion
Ammonia; must be converted to urea by liver and excreted in urine by kidney

46. Which fats are not absorbed like this
Vitamin K - b12 - thiamin - riboflavin
Diarrhea: excess water loss in feces; poor absorption of vitamins - minerals
**NO*** lipase digests fat; no bonds broken by bile; only opens up more SA for lipase
Smaller - more water soluble short - chain FAs go directly to bloodstream at villi capillaries

47. Embryology
Zygote - morula (first four days) - blastocyst (4 day+; implants in uterine lining) - gastrula (2 week) - neurula (3 week)...
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
Peripheral nervous sys
'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.'

48. in fat and liver cells monoglycerides and ffas are once again
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
'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
Reconstituted into TAGs at smooth ER; first stop for most digested fat is liver
Oxytocin and ADH (aka vasopressin)

49. Path of food entering body...
Mouth - esophagus - stomach - duodenum - jejunum - ileum - ascending colon - transverse colon - descending colon - sigmoid colon - rectum - anus
Micelles; micelles (made of bile) go back and forth between brush border and chyme
Corpus luteum degrades into corpus albicans
Homologous chromosomes separate - migrate towards opposite poles/centrioles

50. in mammals - gastrulation involves formation of the
Determination is a pre - programmed fate - differentiation is the actual materialization of that fate
Primitive streak - which consists of cells of the MESODERM ****
Lipoproteins; albumin carries free fatty acids when fat is mobilized from adipose tissue - etc
Nitrogen