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 trop hormone produced by the anterior pituitary gand that targets the adrenal cortex - stimulating it to relase corisol and aldosterone.






2. Chemoreceptors in the upper nasal cavity that respond to odo chemicals.






3. The amount of energy required to produce the transition state of a chemical reaction. If the activation energy for a reaction is very high - the reaction occurs very slowly. Enzymes (and other catalysts) increase reaction rates by reducing activation






4. 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).






5. The rapid mitotic division of a zygot that being within 24-36 hours after fertilization






6. A mechanism by which the stroke volume of the heart is increased by increasing the venous return of the heart (thus stretching the ventricular muscle).






7. A subphase of male orgasm - a reflex reaction triggered by the presence of semen in the urethra. Ejaculation is a series of rhythmic contractions of muscles near teh base of teh penis that increase pressure in the urethra - forcing the semen out.






8. The principal glucocorticoid secreted from teh adrenal cortex. This steroid hormone is released ruing stress - causing increased blood glucose levels and reducing inflammation. The latter effect has led to a clinical use of cortisol as an anti - infl






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






10. The portion of an integral membrane protein that passes through the lipid bilayer.






11. A non - protein - but organic - molecule (such as vitamin) that is covalently bound to an enzyme as part of the active site.






12. Cytoskeletal filaments with a diameter in between that of the microtubule and the microfilament. Intermediate filaments are composed of many different proteins and tend to play structural roles in cells.






13. The third stage of cellular respiration - in which acetyl - CoA is combined with oxaloacetate to form citric acid. The citric acid is then decarboxylated twice and isomerized to recreate oxaloacetate. In the process - 3 molecules of NADH - 1 molecule






14. The majority of the cells surrouding an oocyte in a follicle. Granulosa cells secrete estrogen during the follicular phase of the ovarian cycle (before ovulation).






15. 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.






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






17. An organism that requires the aid of a host organism to survive - and that harms the host in the process.






18. The monomer of a carbohydrate. Monosaccharides have the general chemical formula CnH2nOn - and common monosaccharides include glucose - fructose - galactose - and ribose.






19. Hardy crystals consisting of calcium and phosphate that form the bone matrix.






20. A dense - hard type of bone constructed from osteons (at the microscopic level). Compact bone forms the diaphysis of the the long bones - and the outer shell of the epiphyses and all other bones.






21. Muscles that help focus light on teh retin by controlling the curvature of the lens of the eye.






22. An enzyme that lyses bacterial cell walls. Lysozyme is produced in the end stages of the lytic cycle so that new viral particles can escape their hosst; it is also found in human tears and human saliva.






23. Also called immunoblobins - the antibodies are protiens secreted by B- cells upon activation that bind in a highly specific manner to foreign proteins (such as those found of the surface of pathogens or transplanted tissues). The foreign proteins are






24. A tropic hormone produced by the anterior pituitary gland that targets the thyroid gland - stimulating it to produce and release thyroid hormone.






25. A drop in blood pH due to hypoventilation (too little breathing) and a resulting accumulation of Co2.






26. The fourth and final phase of meiosis II. Telophase II is identical to mitotic telophase - except that the number of chromosomes was reduced by half during meiosis. I.






27. A sensory receptor that responds to hcanges in pressure; for example - there are baroreceptors in the carotid arteries and the aortic ach that monitor blood pressure.






28. Globular protein that assist in DNA packaging in eukaryotes. Histones form octamers around which DNA is wound to form a nucleosome.






29. A bacterium having a rod - like shaped (plural = bacilli).






30. Also known as the gastrointestinal (GI) tract of the digestive tract - the alimentary canal is the long muscular 'tube' that includes the mouth esophagus - somatch - small intesitne - and large intestine.






31. The normal configuration of double - stranded DNA in which the 5' end of oen strand is paired with the 3' end of the other






32. A virus with an RNA genome (e.g. HIV) that undergoes a lysogenic life cycle in a host with a double stranded DNA genome. In order to integrate its genome with the host cell genome - the virus must first reverse trasncribe its RNA genome to DNA.






33. A set of veins that connect a capillary bed in the hypothalamus (the primary capillary plexus) with a capillary bed in the anterior pituitary gland (the secondary capillary bed). Releasing and inhibiting factors from the hypothalamus travel along the






34. A protein channel in the nuclear envelope that llows the free passage of molecules smaller than 60 kD.






35. A waste product of protein dbreakdown - produced by the liver and relased into the bloodstream to be eliminated by the kidney.






36. The blood vessel that carries deoxygenated from the right ventricle of the heart to the lungs.






37. A stack of membranes found near the rough ER in eukaryotic cells that is involved in the secretory pathway. The Golgi is involved in protein glycosylation (and other protein modification) and sorting and packagin proteins.






38. The mass of cells in the blastocyst that ultimately give rise to the embryo and other embryonic structues (the amion - the umbilical vessels - etc.)






39. A chemical derived from vitamin A found in the pigment proteins of the rod photoreceptors of the retina. Retinal changes conformation when it absorbs light - triggering a series of reactions that ultimately result in an action potential being sent to






40. The fourth (and final) phase of mitosis. During telophase the nuclear envelope reforms - chromosomes decondense - and the mitotic spindle is disassembled.






41. Connective tissue with large amounts of either collagen fibers (making them strong) or elastic fibers - or both. Dense tissues are typically strong (e.g. bone - cartilage - tendons - etc.)






42. Small paired gland found inferior to the prostate in males and at the posterior end of the penile urethra. They secrete an alkaline mucus on sexual arousal that helps toneutralize any traces of acidic urine the urethra that might be harmful to sperm.






43. Pairing of homologus chromosomes in a diploid cell - as occurs during prophase I of meiosis.






44. A function of the reproductive system controlled by the sympathetic nervous system. In males - organs includes emission and ejaculation; in females it is mainly a series of rhythmic contraction of the pelvic floor muscles and the uterus.






45. The central structure of the diencephalon of the brain. the thalamus acts as a relay station and major integrating area for sensory impulses.






46. The primary enzyme in peroxisomes; catalse catalyzes the hydrolysis of hydrogen peroxide (H2O2) into water and oxygen.






47. An enzyme that polymerizes a strand of DNA by reading an RNA template (an RNA dependent DNa polymerase); used by retrovirus in order to integrate their genome with the host cell genome.






48. A nonliving - intracellular parasite. Viruses are typically just pieces of nucleic aid surrounded by a protein coat.






49. The first phase of meiosis I. During prophase I the replicated chromosomes condense - homologous chromsomes pair up - crossing over occurs between homologous chromosomes - the spindle is formed - and the nuclear envelope breaks apart into vesicles. P






50. The hollow center of an osteon - also known as a Haversian canal. The central canal contains blood vessels - lymphatic vessels - lymphatic vessels - and nerves. Bone is laid down around the central canal in concentric rings called lamellae.