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 do villli do
sucrose (gluc+fruc) - lactose (gluc+galactose) - starch (gluc+gluc)
Increase surface area of sm intestine; this improves digestion (enzymes adsorbed to villi) and absorption
FAT=9 cal per gram Carbs=4.5 cal per gram - Prot=4 cal per gram - these seem to be for anhydrous forms
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

2. At post - two weeks ovulation
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.
Diarrhea: excess water loss in feces; poor absorption of vitamins - minerals
Corpus luteum degrades into corpus albicans
On the chyme exiting the stomach and entering duodenum thru the pyloric sphincter

3. in the presence of ADH what happens to movement of water across nephron membr
Water flows from the tubule - concentrating the filtrate - raising BP
FAT=9 cal per gram Carbs=4.5 cal per gram - Prot=4 cal per gram - these seem to be for anhydrous forms
Glucose and ketone bodies (not from glycogen stores)
Liver is the control center for blood glucose; is fed by portal vein from sm intest

4. Most important nutrients absorbed by large intestine
Lots of water - minerals (electrolyte balance) - vitamins (aided by gut bacteria)
Has memb - bound organelles - etc...
Drugs - toxins - bile pigments (color the urine) - uric acid - antibiotics
Increases surface area of food ball (bolus)

5. How does glycogen compare to starch
Posterior pituitary hormone; acts on uterus - mammary glands; causes uterine contractions - milk ejection
vitreous humor - retina - fovea
It is the animal counterpart of starch; it is more highly- branched - thus releases more glucose monomers upon repeated hydrolysis than starch
Alpha 1-4 and 1-6 (branching) glycosidic linkages

6. Some PNS nerves are found in brain - spinal cord
(diploid organism) humans are part of gametic life cycle ie produce gametes; diploid germ - line stem cells undergo meiosis to form haploid gametes
Contains lysozyme - which regulates bacteria within intestine; breaks down peptidoglycans (**bact wall); innate immunity
Eg spinal nerve - cranial nerve; Not All Nervous Tissue In Brain - SC Is CNS Tissue
Inner lining of circulatory system

7. The EYE
Focuses light thru the vitreous humor onto retina; acts as a converging lens (image is real - inverted)
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
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
Processes: axons - dendrites

8. axon hillock physiology
Conjunction of cell body w/axon
Di - tri - peptides; inside enterocytes are hydrolyzed to amino acids
Two perpendicular semicircular canals involved in balance - equilibrium
HCl; secreted by parietal cells under stim by gastrin

9. thyroid hormones: Not All One Kind of HORM
Glycosaminoglycans - prots - AAs - lipids
Increase surface area of sm intestine; this improves digestion (enzymes adsorbed to villi) and absorption
On the chyme exiting the stomach and entering duodenum thru the pyloric sphincter
Calcitonin (peptide; lowers blood Ca); T3/T4 (tyrosine - derived; increase basal metabolic rate); T4= thyroxine

10. Meiosis I Metaphase I
Interneurons working to integrate signals received from the peripheral nervous system (sense organs)
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
After morula - with blastocyst (+8 cell count)--->totipotent to embryonic stem cell and so on
Ganglion

11. Induction affects...
Di - tri - peptides; inside enterocytes are hydrolyzed to amino acids
Direction of differentiation
Development of placenta begins with implantation; eventually - by end of first trimester - placenta will replace corpus luteum and its estrogen/progest secretions
The renal corpuscle

12. peroxisome is derived from this
It is the animal counterpart of starch; it is more highly- branched - thus releases more glucose monomers upon repeated hydrolysis than starch
Uncontracted: parasymp (eg opoid use)
(diploid organism) humans are part of gametic life cycle ie produce gametes; diploid germ - line stem cells undergo meiosis to form haploid gametes
ER

13. What does peptic refer to in general
Tight regulation of parietal cells needed b/c gastric acid secretion is E- intensive; parietal cells are hi in mitochons
Nuclear envelope reassembled in daughter cells; cytokinesis occurs; nucleoli reappear (site of rRNA synthesis)
Digestion
Gastric inhibitory pep; increase of pancreatic - enz activating enzymes (which cleaves zymogens like trypsinogen); increased gall bladder contraction; decreases stomach mobility

14. interneurons
Calcitonin (peptide; lowers blood Ca); T3/T4 (tyrosine - derived; increase basal metabolic rate); T4= thyroxine
An endogenous morphine
Transfer signals from neuron - neuron; 90% of neurons are interneurons
Stores blood: when expanded liver serves as blood reservoir for body - filters blood: Kupfer cells phagocytize bacteria picked up from intestines - destroys bad RBCs: also done by Kupfer cells - detoxifies blood: detoxified chemicals are excreted eit

15. Where does the juxtaglomerular apparatus come into play...renin --->inc angiotensins -->inc aldosterone - ups BP
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
Calcitonin (peptide; lowers blood Ca); T3/T4 (tyrosine - derived; increase basal metabolic rate); T4= thyroxine
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
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... ...

16. 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
Secreted by delta cells of Islets of langerhans; inhibits insulin and glucagon; slows digestion
Prophase I: crossing over occurs; nuclear envelope is absorbed into ER; chromosomes condense)
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
Parathyroid hormone (peptide; increases blood Ca); thus - might increase osteoclast/decrease osteoblast activity

17. Polypeptides are formed with what kind of reaction?
Thru tight junctions by favorable osmotic gradient
Nuclear envelope reassembled in daughter cells; cytokinesis occurs; nucleoli reappear (site of rRNA synthesis)
Dehydration reaction; broken apart with enzyme - catalyzed hydrolysis
Below hypothalamus

18. What is endothelium?
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
Mediate complex cell processes thru eg phosphorylation via secondary messenger (G protein) systems = signal transduction pathway - GPCR (G protein coupled receptor)
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
Inner lining of blood vessels

19. Liver Functions
Many modern drugs are ligands for GPCRs
Injury that does not sever SC (causes deep lesion from back - front) might cause loss of feeling without full loss of motion
Stores blood: when expanded liver serves as blood reservoir for body - filters blood: Kupfer cells phagocytize bacteria picked up from intestines - destroys bad RBCs: also done by Kupfer cells - detoxifies blood: detoxified chemicals are excreted eit
Direction of differentiation

20. components of interstitial fluid
Processes: axons - dendrites
Glycosaminoglycans - prots - AAs - lipids
Nitrogen
Nourishes follicle growth; stimulates granulosa cell growth around primary oocyte at puberty = primary follicle; also - stimulates Sertoli cells in males

21. portal vein physiology...

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

22. important because in meiosis germ - line cells begin as 46 2N w/ 23 pairs of homologous chromosomes which are replicated in S phase of interphase to 23 pairs of sister chromatids = still 46 2N
Note: enteric= small intestine - double layer of peritoneum that suspends jejunum/ileum from posterior abdominal wall = connective tissue
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
Salivary amylase (weak); sm intest amylase (breaks down large polysaccharides)
Has memb - bound organelles - etc...

23. FLAT PG: prolactin
Buildup of macromolecules in lysosome due to deficient lysosome enzymes
Arrested at primary oocyte; hypothalamus GnRH->FSH released at puberty stims granulosa cell development; granulosa secrete zona pellucida = primary follicle
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
Peptide; prolactin promotes milk production; prolactin release is stimulated by act of suckling - which in turn inhibits menstrual cycle

24. In general - parietal=
The wall of the body or of a body cavity or hollow structure
Lumen (ie continuous w/body cavity) and cytosol
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
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

25. Where are these exocrine glands located
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)
Gall bladder - pancreatic secretions increase - arrive via ampulla of vater (duct glands); insulin secretion increases (fed state; ductless glands)
Liposome has phospholipid bilayer
In gastric pits; secretions combine into gastric juice

26. sensory (afferent)/interneurons/motor (efferent)
Stores blood: when expanded liver serves as blood reservoir for body - filters blood: Kupfer cells phagocytize bacteria picked up from intestines - destroys bad RBCs: also done by Kupfer cells - detoxifies blood: detoxified chemicals are excreted eit
Neurons may perform one of three functions....
Determination is a pre - programmed fate - differentiation is the actual materialization of that fate
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)

27. what happens when glycogen stores are saturated and blood sugar remains high?
Fat synthesis; carbs stored as free fatty acids - esterified to TAGs (requires small amount of E)
Liver breaks down glycogen (glycogenolysis); at hi blood sugar it builds up glycogen (glycogenesis)
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
Inner lining of blood vessels

28. Does bile digest fat?
Peristalsis (esophagus) and segmentation (bi - directional=mixing)
**NO*** lipase digests fat; no bonds broken by bile; only opens up more SA for lipase
Secondary spermatocyte (stim'd by FSH from Sertoli cells -->EQUATIONAL DIVISION-->spermatid - which matures further into spermatozoa; released into semeniferous tubule; transported to epididymis
An ether phospholipid; hi conc in myelin; thus - hi conc in heart tiss - nervous tiss

29. What is secreted into filtrate by cells of the proximal tubule?
PH 6.0; this accomplished by pancreatic secretion of bicarbonate which ups pH
Needs time for bile - lipase - micelle migration - enterocyte uptake
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
Drugs - toxins - bile pigments (color the urine) - uric acid - antibiotics

30. What testosterone released by secondary follicle by LH stim is converted to...
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
Small amounts of hydrolyzed phospholipids and cholesterol: like other fat mols these can diffuse thru enterocyte membrane
Estradiol (estrogen - steroid horm); prepares uterine wall for pregnancy; just before ovulation - release of estradiol stims LH in pos feedback
Break down TAGs to monoglycerides and free fatty acids

31. Examples of GPCRs in sensory systems/signal transduction: What is the ligand or messenger in each case? ...SIGHT - SMELL - MOOD - FIGHT/FLIGHT etc
Secreted by implanted egg; HCG prevents degeneration of the corpus luteum; HCG in blood/urine is first sign of pregnancy
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
- 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
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

32. Seen in lysosomal storage diseases
Smaller - more water soluble short - chain FAs go directly to bloodstream at villi capillaries
Buildup of macromolecules in lysosome due to deficient lysosome enzymes
Maintains hi estrogen levels; body does not recognize luteal surge - ovulation does not occur; hi progesterone can lessen shedding by thickening the uterine lining
Inner lining of circulatory system

33. Local vs long - distance mediators
Chyme (by combined activity of exocrine glands)
Smaller - more water soluble short - chain FAs go directly to bloodstream at villi capillaries
Testosterone and estradiol
Paracrine (local) - endocrine (longer distance)

34. signal transduction occurs by 2 paths
In gastric pits; secretions combine into gastric juice
Abdominal cavity - which is coated in serous fluid
1) by integral ion channels 2) transmitted by second messenger system
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

35. Tight junctions
Conjunction of cell body w/axon
Form barrier to extracellular fluid
Secreted by delta cells of Islets of langerhans; inhibits insulin and glucagon; slows digestion
Duodenum (wraps around pancreas; most digestion occurs here) - jejunum (pH 7-9; 2m) - ileum

36. FLAT PG: FSH
Mediate complex cell processes thru eg phosphorylation via secondary messenger (G protein) systems = signal transduction pathway - GPCR (G protein coupled receptor)
Alpha cells; stims gluconeogenesis in liver; acts via cAMP second messenger
Stores blood: when expanded liver serves as blood reservoir for body - filters blood: Kupfer cells phagocytize bacteria picked up from intestines - destroys bad RBCs: also done by Kupfer cells - detoxifies blood: detoxified chemicals are excreted eit
Nourishes follicle growth; stimulates granulosa cell growth around primary oocyte at puberty = primary follicle; also - stimulates Sertoli cells in males

37. Gland: ovaries
Pancreatic duct (made of acinar cells?)
Fructose is a structural isomer of glucose
Spike in estrogen - LH levels; secondary follicle bursts - releases into body cavity - swept along by fimbriae
Estrogen: steroid; stims LH in luteal surge; causes growth of female sex organs progesterone: prepares/maintains uterus for pregnancy

38. pancreatic enzymes are zymogens
Trypsinogen is activated by enterokinase in the brush border; in turn - it activates other enzymes
Secreted by delta cells of Islets of langerhans; inhibits insulin and glucagon; slows digestion
Break down TAGs to monoglycerides and free fatty acids
Creates one ovum (23 N) and three polar bodies

39. Different tissues working together
Interneurons working to integrate signals received from the peripheral nervous system (sense organs)
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
Organs
Polysaccharides w/proteoglycans attached = glycosaminoglycans; often give pliability

40. cytosol pH
Beta cells
Somatic nervous sys - autonomic nervous sys
About 7.2
Contains hydrolytic enzymes; thus - digests endocytosed substances; derived from golgi

41. How does blood sugar move into tissues?
Facilitated diffusion from hi to lo conc
Testosterone upon stim by LH
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
All carbs absorbed at enterocytes are carried to liver by portal vein

42. at lo blood sugar...
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)
Liver breaks down glycogen (glycogenolysis); at hi blood sugar it builds up glycogen (glycogenesis)
The wall of the body or of a body cavity or hollow structure
Formed in kidney (nephron) - sent thru renal pelvis - down ureter to bladder - drained by urethra'

43. parathyroid hormone
Alpha 1-4 and 1-6 (branching) glycosidic linkages
Salivary amylase (weak); sm intest amylase (breaks down large polysaccharides)
Fat synthesis; carbs stored as free fatty acids - esterified to TAGs (requires small amount of E)
Increases blood Calcium

44. Bile salts and lipase
Somatic nervous sys - autonomic nervous sys
Epithelial tissue near semniferous tubules
Visceral layer= parietal layer; serous membrane is the container of the coelom/peritoneal cavity
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

45. exocrine types
Sudiferous (sweat) - sebaceous - digestive (bile - pancreatic enzs) - mucosal
pericardial cavity - pleural cavity (contains lungs) - peritoneal cavity (abdominal)
Nervous - muscle - epithelial (defines inner/outer) - connective (extensive matrices)
Facilitated diffusion from hi to lo conc

46. Important aspect of crypt of Lieberkuhn - secreted intestinal juice
Contains lysozyme - which regulates bacteria within intestine; breaks down peptidoglycans (**bact wall); innate immunity
Fallopian tubes
The renal corpuscle
Lots of water - minerals (electrolyte balance) - vitamins (aided by gut bacteria)

47. During ejaculation - sperm...

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

48. So - following blastocyst implantation (4d) - at approx 2 weeks past fertilization
***nicotinic is ionotropic; muscarinic is GPCR
(diploid and haploid individuals = ALTERNATION of GENERATIONS) a fusion of gametic and zygotic life cycles
Abdominal cavity - which is coated in serous fluid
Gastrulation occurs: formation of three primary germ layers = differentiation

49. What is a plasmalogen?
Follicular (proliferative)= 8d - Luteal (post - ovulation; corpus luteum secretions)= 13d - Menstruation (shed uterine lining if no implantation)= 5
Many modern drugs are ligands for GPCRs
An ether phospholipid; hi conc in myelin; thus - hi conc in heart tiss - nervous tiss
Gastrulation occurs: formation of three primary germ layers = differentiation

50. Where does fertilization occur
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... ...
Fallopian tubes
Fat is insoluble in blood and requires a carrier like lipoproteins (vLDL...HDL) or albumins; ...vLDL has hi triglycerides - hi cholesterol
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