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 systme of ductless glands taht secrete chemical messengers (into) the blood - has to be into the blood.






2. An integral membrane proteint hat binds extracellular signaling molecules - suchas hormones and peptides.






3. (Singular:villus). Folds of the intestinal mucosa that project into the lumen of the intestine; vili serve to increase the surface area of the intestine for absorption.






4. The movement of a hydrophobic molecule across the plasma membrane of cell - down its concentration gradient. Since the molecule can esialy interact with the lipid bilayer - no additional help (such as a channel or pore) is required.






5. An ion channel specific for potassium found in the plasma membrane of all cells in the body. Leak channels are constitutively open and allow their specifi ion to move across the membrane according to its gadient. Potassium leak channels allow potassi






6. The deliberate exposure of a person to an antigen in order to provoke the primary immune response and memory cell production. Typically the antigens are those normally associated with pathogens - thus if the live pathogen is encountered in the future






7. Photoreceptors in the retina of the eye that responds to bright light and provide color vision.






8. 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.






9. The third phase of the uterin (endometrial) cycle - during which the rebuilt endometrium is enhanced with glycogen and lipid stores. The secretory phase is primarily under the controll of progestone and estrogen (secreted from the copus luteum during






10. An enzyme that unwinds the double helix of DNA and separates the DNA strands in preparation for DNA replication.






11. A type of mutation in DNa where a single base is substituted for another.






12. 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






13. A subsequent immune response to previously encountered antigen that results in antibody production and T cell activation. The secondary immune response is mediated by memory cells (produced during the primary immune respone) and is much faster and st






14. A lipid bilayer that surrounds the capsid of an animal virus. the envelope is acquired as teh virus buds out through the plasma membrane of its host cell. Not all annimal viruses possess and envelope.






15. Pepsinogen - secreting cells foudn at teh bottom of the gastric glands






16. A carrier protein that transports two molecules across the plasma membrane in the same direction. For example - the Na+- glucose cotransporter in intestinal cells is a symporter.






17. A function in the reproductive system - controlled by the parasympathetic nervous system - that includes erection (via dilation of erectile arteries) and lubrication.






18. The first portion of the nephron tubuel after the glomerulus. THe PCT is the site of most reabsorption; all filtered nutrients are reabsorbed here as well as most of the filtered water.






19. The protective - connective tissue wrapping of the central nervous system (the dura mater - arachnoid mater - and pia mater).






20. The bond formed between the carboxyl group of one amino acid and the amino group of another.






21. A hair - like structure on teh cell surface composed of microtubules ina '9+2' arrangement (nine pairs of microtubles surrounding 2 single microtubules in the center). Teh microtubules are conneted with a contractile protien called dynein. Cilia beat






22. A haploid but immature cell resulting from the second meiotic division f spermatogenesis. Spermatids undergo significant physical changes to become mature sperm (spermatozoa).






23. Integration by a postsynaptic neuron of inputs (EPSPs and IPSPs) from multiple sources.






24. A type of lipoprotein; the form in which absorbed fats from the intestines are transported to the circulatory system.






25. Specialized tissue with a lot of space that can fill with blood upon proper stimulation - causing teh tissue to become firm. Erectile tissue is found in the penis - the clitoris - the labia - and the nipples.






26. A group of three nucleotides taht is specific for a particular amino acid - or that specifies 'stop translating'






27. Receptors in the central nervous system that monitor the pH of cerebrospinal luid to help regulate ventilation rate.






28. A point mutation in which a codon that specifies an amino acid is mutated into a codon that specifies a different amino acid.






29. A carrier protein that transports a single molecule across the plasma membrane.






30. A digestive accessory organ near the liver. The gallbladder stores and concentrates bile produced by the liver - and is stimulated to contrat by cholecystokin (CCK).






31. The layer of granulosa cells taht surround an oocyte after is has been ovulated.






32. A pathway through a plasma membrane that restrics passage based only on the size of the molecules. Pore are made from porin proteins.






33. A concentrated region of white blood cells found along the vessels of the lympatic system.






34. A fibrous - connective - tissue protein taht has the ability to recoil to its original shape after being stretche.d Elastin is found in great amounts in lung tissue - arterial tissue - skin - and the epiglottis.






35. The portion of the hindbrain that controls respiratory and blood pressure - and specialized digestive and respiratory functions such as vomiting - sneezing - and coughing.






36. The function unit of the kidney. Each kidney has about a million nehprons; this is where blood filtration and subsequent modification of the filtrate occurs. The nephron empties into collecting ducts - which empty into the ureter.






37. An abdominal organ that is considered part of the immune system. THe spleen has four functions: (1) it filters antigen from the blood (2) it is the site of B cell maturation - (3) it stors blood - and (4) it destroys old red blood cells.






38. A thick - gelatinous fluid found in the posterior segment of the eye (between the lens and the retina). The vireous humor is only produced during fetal development and helps maintain intraocular pressure (the pressure inside the eyeball).






39. A chromosome that does not determine gender (is not a sex chromosome). Humans have two sex chromsomes and 22 autosomes.






40. Aromatic bases found in DNA and RNA that are derived from purine. They have a double rightn structure and include adenine and guanine.






41. Sperm production; occurs in human males on a daily basis from puberty until death. Spermatogenesis results in the production of four mature gametes (sperm) from a single precursor cell (spermatogonium). For maximum sperm viability - spermatogenesis r






42. Movement across the membrane of a cell that does not require energy input from the cell. Passive transport relies on concentration gradients to provie the driving force for movement - and includes both simple and facilitated diffusion.






43. The curled structure in the inner ear that contains the membranes and hair cells that transduce sound waves into action potentials.






44. The first phase of the ovarian cycle - during which a follicle (an oocyte and its surroudning cells) enlarges and matures. This phase is under the control of FSH from the anterior pituitary - and typically lasts from day 1 to day 14 of the menstrual






45. A neuron with a single axon and a single dendrite - often projecting from opposite sides of the cell body. Bipolar neurons are typically associated with sensory organs; an example is the bipolar neuron in the retina of the eye. - note that one axon m






46. The perio dof tim ein a woman's life when ovulation and menstruation cease. Menopause typically begins in the late 40s.






47. One of the four aromatic bases found in DNA and RNA. Guanine is a purine; it pairs with cytosine.






48. An ion channel that is constitutively open - allowing the movement of teh ion across the plasma membrane according to its concentration gradient.






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






50. The portion of the nephron after the glomerulus and apsule; the region of the nephron where the filtrate is modified along its path to becoming urine.