Test your basic knowledge |

MCAT Prep Biology

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. A short period of time **prior to exponential growth of a bacterial population during which no - or very limited - cell division occurs.






2. A solid clump of cells resulting from cleavage in the early embryo. Because there is very little growth of these cells during cleavage - the morula is ony about as large as the original zygote.






3. Three loop - like structures in the inner ear that contain sensory receptors to monitor balance.






4. The neurotransmitter used by the sympathetic division of the ANS at the postganglionic (organ - level ) synapse.






5. Something that works together with another thing to augment the the second thing's activity. For example - a uscle that assists another muslce is said to be a syngergist. An enzyme that helps another enzyme is a synergist.






6. The nervous system of the gastrointestinal tract. It controls secretion and motility within teh Gi tract - and is linked to the central nervous system.






7. Human Chorionic Gonadotropin - a hormone secreted by the trophoblast cells of a blasocyst (i.e. developing embryo) that prolongs the life of the corpus luteum - and thus increases the duration and amount of secreted progesterone. This helps to mainta






8. One of several vessels that carry oxygenated blood from the lungs to the left atrium of the heart.






9. A contractile protein. In skeletal and cardiac muscle - actin polymerizes (along with other proteins) to form the thin filaments. Actin is involved in many contractile activities - such as cyotkinesis - pseudopod formation - and muscle contraction.






10. One of several different nutrietns that must be consumed in the diet - and generally not synthesized in the body. Vitamins can be hdyrophobic (fat - solube) or hydrophilic (water - soluble).






11. The inner epithelial lining of the uterus that thickens and develops during the menstrual cycle - into which a fertilized ovum can implant - and which sloughs off during menstration if a pregnancy does not occur.






12. Cranial nerve pair X. The vagus nerves are very large mixed nerves (They carry both sensory input and motor input) that innervate virtually every visceral organ. They are especially important in transmitting parasympathetic input to the heart and dig






13. An irritation of a tissue caused by infection or injury. Inflammation is characterized by four cardinal symptoms; redness (rubor) - swelling (tumor) - heat (calor) - and pain (dolor).






14. One of the three primary (embryonic) germ layers formed during gastrulation. Ectoderm ultimately forms external structures such as the skin - hair - nails - and inner linings of the mouth and anus - as well as the entire nervous system.






15. A form of genetic recombination in bacteria in which plasmid and/or genomic DNA is transferred from one bacterium to the toher through a conjugation bridge.






16. A protein hormone secreted by sustenacular cells of the testes that acts to inhibit the release of FSH and LH from the anterior pituitary.






17. The movement of a substance from the filtrate (in the renal tuble) bak into the bloodstream. Reabsorption reduces the amount of a substance in the urine.






18. The relationship of muscle length to its ability to generate strong contractions. Maximum tension (contraction strength) is achieved at sarcomere lengths between 2.0 and 2.2 microns. Tension decreases outside of this range <-- remember.






19. The first branches of the trachea. There are two primary bronchi - one for each lung.






20. The 'language' of a molecular biology that specifies which amino acid corresponds to which three - nucleotide group (codon).






21. A region within the nucleus where rRNA is transribed and ribosomes are partially assembled.






22. The tendency of certain factors to stablize the hemoglobin in the tense conformation - thus reducing its affinity for oxygen and enhancing the relase of oxygen to the tissues. The factors include increased PCO2 - increase temperature - increased bisp






23. Also called transverse tubules - these are deep invaginations of the plasma membrane found in skeletal and cardiac muscle cells. These invaginations allow depolarization of the membrane to quickly penetrate to the interior of the cell.






24. The first phase of meiosis II. Prophase II is identical to mitotic prophase - except that the number of chromosomes was reduced by half during meiosis I.






25. The volume of blood pumped out of the heart in one minute (vol/min); the product of the stroke volume (vol/beat) and the heart rate (beat/min). Cardiac output is directly proportional to blood pressure**.






26. Produced in muscle cells from the reduction of pyruvate (under anaerobic conditions) to regenerate NAD+ so that glycolysis can continue. A rise in lactic acid usually accompanies an increase in physical activity.






27. One type of eukaryotic mRNA processing in which introns are removed from the primary transcript and exons are ligated together. SPlicing of transcripts can be different in different tissues.






28. The mechanism of contraction in skeletal and cardiac muscl cells. It is a series of four repeated steps: (1) myosin binds actin - (2) myosin pull actin toward the center of the sarcomere (3) myosin releases actin - and (4) myosin resets to its high -






29. A dense grwoth of bacteria that covers the surface of a petri dish.






30. The location on a chromosome where transcription begins.






31. The law of conservation of energy; the energy of the universe is constant - thus if the energy of a system increases - the energy of its surroundings must decrease - and vice versa.






32. A blood protein produced by the liver. Albumin helps to mantain blood osmotic pressure (oncotic pressure)






33. The pressure measured in the arteries during contraction of the ventricles (during systole).






34. A generic connective tissue cell that produces fibers; the progenitor of all other connective tissue cell types.






35. The cellular elements of blood; erythrocytes - leukocytes - and platelets.






36. The specific site on an antigenic molecule that binds to a T cell receptor or to an antibody.






37. A hormone secreted by the small intestine (duodenum) in response to the presence of food. It decreases the rate at which chyme leaves the stomach and enters the small intestine.






38. Enzymes that degrade various macromolecules and that require an acidic pH to function properly. Acid hydrolases are found within the lysosomes of cells.






39. Something that increases the rate of a chemical reaction by reducing the activation energy for that reaction. The free energy of reaction remains unchanged.






40. The reduction of pyruvate to either ethanol or lactate in order to regenerate NAD+ from NADH. Fermentation occurs in the absence of oxygen - and allow glycolysis to continue under those conditions.






41. The first step in viral infection. Attachemen of a virus to its host is very specific and is also known as adsorption.






42. General - non - specific protection to the body - including the skin (barrier) - gastric acid - phagocytes - lysozyme - and complement.






43. The enzyme that catalyzes the phosphorylation of fructose -6- phosphate to form fructose -1-6- bisphosphate in the third step of glycolysis. This is the main regulatory step of glycolysis. PFK is feedback - inhibited by ATP.






44. A hormone secreted by the anterior pituitary that tarets the mammary glands stimulating them to produce breastmilk.






45. A nucleotide sequence on DNA that contians three elemtns: a coding sequence for one or more enzymes - *a coding sequence for a regulatory protein - and upstream regulatory sequences where the regulatory proteins can bind. An example is the lac operon






46. Extremely small pseudo - cells in the blood - important for clotting. They are not true cells - but are broken - off bits of a larger cell (a megakaryocyte).






47. A chemical secreted by a T cell (usually the helper Ts) that stimulates activation and proliferation of other immune system cells.






48. A projection of the cell body of a neuron that recieves a nerve impulse form a different neuron and send the impulse to the cell body. Neurons can have one or several dendrites!






49. The formation of haploid gametes (sperm or ova) via meiosis.






50. An asexual method of bacterial reproduction that serves only to increase the size of the population; ther is no introduciton of gnetic diversity. THe bacterium simply grows in size until it has doubled its cellular components - then it replicates its