test 2

5. Which system helps fight illness? a. Immune system b. Digestive system c. Nervous system d. Urinary system

A: The immune system helps protect the body from bacteria, viruses, infections, and other elements that could cause illness. The digestive system breaks down food for the body. The urinary system helps the body expel liquid waste.

2. Which item below is NOT part of the digestive system? a. Stomach b. Brain c. Mouth d. Esophagus

2. B: The digestive system helps the body process food. The stomach, mouth, and esophagus all participate in food digestion. The brain, however, is part of the nervous system.

1. Which item below is part of the circulatory system? a. Kidneys b. Lungs c. Heart d. Stomach

1. C: The circulatory system circulates materials throughout the entire body. The heart is part of this system, since it is responsible for pumping blood that carries these materials. The kidneys are part of the urinary system. The lungs belong to the respiratory system, and the stomach is part of the digestive system.

10. Of the following, the blood vessel containing the least-oxygenated blood is: a. The aorta b. The vena cava c. The pulmonary artery d. The capillaries

10. C: The pulmonary artery carries oxygen-depleted blood from the heart to the lungs, where CO2 is released and the supply of oxygen is replenished. This blood then returns to the heart through the pulmonary vein, and is carried through the aorta and a series of branching arteries to the capillaries, where the bulk of gas exchange with the tissues occurs. Oxygen-depleted blood returns to the heart through branching veins (the femoral veins bring it from the legs) into the vena cava, which carries it again to the heart. Since the pulmonary artery is the last step before replenishment of the blood's oxygen content, it contains the blood which is the most oxygen depleted.

11. Which layer of the heart contains striated muscle fibers for contraction of the heart? a. Pericardium b. Epicardium c. Endocardium d. Myocardium

11. D: The myocardium is the layer of the heart that contains the muscle fibers responsible for contraction (Hint: myo- is the prefix for muscle). The endocardium and epicardium are the inner and outer layers of the heart wall, respectively. The pericardium is the sac in which the heart sits inside the chest cavity.

12. Which blood vessel carries oxygenated blood back to the heart? a. Pulmonary vein b. Pulmonary artery c. Aorta d. Superior vena cava

12. A: This is a tricky question; most of the time, veins carry deoxygenated blood and arteries carry oxygenated blood. However, in this case, the pulmonary veins carry oxygenated blood from the lungs to the heart and the pulmonary arteries carry deoxygenated blood from the heart to the lungs.

13. Mrs. Jones's class conducted an experiment on the effects of sugar and artificial sweetener on the cookie recipe's overall color when baked. What would be the independent variable in the cookie experiment? a. The students should use the same ingredients in both recipes, but bake the cookies with sugar at 450 degrees and those with artificial sweetener at 475 degrees. They should increase the baking time on the artificial sweetener cookies, since the package instructs them to do so b. The students should use the same ingredients in both recipes, but increase the baking time on the artificial sweetener cookies, since the package instructs them to do so c. The students should use the same ingredients, same baking temperatures, and same baking times for both recipes d. The students should use the same ingredients and baking times in both recipes, but bake the cookies with sugar at 450 degrees and the artificial sweetener cookies at 475 degrees

13. C: The independent variable is the variable that is changed in the experiment in order to determine its effect on the dependent variable or the outcome of the experiment. The dependent variable results from the experimenter making only one change to an experiment that can be repeated with the same results. Mrs. Jones's class was comparing the effects of sugar and artificial sweetener on the overall color of cookies once they are baked; thus, the one thing that should be changed in the experiment is the sugar and artificial sweetener in the recipe. All of the other

14. Which part of the cell is often called the cell "power house" because it provides energy for cellular functions? a. Nucleus b. Cell membrane c. Mitochondria d . Cytoplasm

14. C: Mitochondria are often called the power house of the cell because they provide energy for the cell to function. The nucleus is the control center for the cell. The cell membrane surrounds the cell and separates the cell from its environment. Cytoplasm is the thick fluid within the cell membrane that surrounds the nucleus and contains organelles.

15. What function do ribosomes serve within the cell? a. Ribosomes are responsible for cell movement. b. Ribosomes aid in protein synthesis. c. Ribosomes help protect the cell from its environment. d. Ribosomes have enzymes that help with digestion.

15. B: Ribosomes are organelles that help synthesize proteins within the cell. Cilia and flagella are responsible for cell movement. The cell membrane helps the cell maintain its shape and protects it from the environment. Lysosomes have digestive enzymes.

16. What is the most likely reason that cells differentiate? a. Cells differentiate to avoid looking like all the cells around them. b. Cells differentiate so that simple, non-specialized cells can become highly specialized cells. c. Cells differentiate so that multicellular organisms will remain the same size. d. Cells differentiate for no apparent reason.

16. B: Cells differentiate so that simple, less specialized cells can become highly specialized cells. For example, humans are multicellular organisms who undergo cell differentiation numerous times. Cells begin as simple zygotes after fertilization and then differentiate to form a myriad of complex tissues and systems before birth.

17. How is meiosis similar to mitosis? a. Both produce daughter cells that are genetically identical. b. Both produce daughter cells that are genetically different. c. Both occur in humans, other animals, and plants. d. Both occur asexually

17. C: Both meiosis and mitosis occur in humans, other animals, and plants. Mitosis produces cells that are genetically identical, and meiosis produces cells that are genetically different. Only mitosis occurs asexually.

18. In the suburban neighborhood of Northwoods, there have been large populations of deer, and residents have complained about them eating flowers and garden plants. What would be a logical explanation, based on observations, for the large increase in the deer population over the last two seasons? a. Increased quantity of food sources b. Decreased population of a natural predator c. Deer migration from surrounding areas d. Increase in hunting licenses sold

18. B: A decrease in a natural predator, such as a wolves, coyotes, bobcat, or wild dogs, would allow the population to become out of control. In a population of deer that has increased, there would be a natural decrease in a food source for the nutritional needs for the animals. Although deer have been known to share a human's developed habitat, it is often forced by reduced territory and food sources. An increase in hunting licenses would be used by local officials to try to control the population, helping to decrease the number of adults of breeding age.

19. How do DNA and RNA function together as part of the human genome? a. DNA carries genetic information from RNA to the cell cytoplasm. b. RNA carries genetic information from DNA to the cell cytoplasm. c. DNA and RNA carry genetic information from the cell nucleus to the cytoplasm. d. DNA and RNA do not interact within the cell.

19. B: DNA is the primary carrier of genetic information in most cells. RNA serves as a messenger that transmits genetic information from DNA to the cytoplasm of the cell.

20. The majority of nutrient absorption occurs in the: a. mouth b. stomach c. small intestine d. large intestine

20. C: Food enters the digestive system through the mouth and proceeds down to the stomach after mastication by the teeth. Once in the stomach, enzymes are secreted that begin to digest the specific substances in the food (proteins, carbohydrates, etc). Next, the food passes through to the small intestine where the nutrients are absorbed and then into the large intestine where extra water is absorbed.

21. What process should the DNA within a cell undergo before cell replication? a. The DNA should quadruple so that daughter cells have more than enough DNA material after cell division. b. The DNA should triple so that daughter cells have three times the amount of DNA material after cell division. c. The DNA should replicate so that daughter cells have the same amount of DNA material after cell division. d. The DNA should split so that daughter cells have half the amount of DNA material after cell division.

21. C: After cell division, the daughter cells should be exact copies of the parent cells. Therefore, the DNA should replicate, or make an exact copy of itself, so that each daughter cell will have the full amount of DNA.

22. What basic molecular unit enables hereditary information to be transmitted from parent to offspring? a. Genes b. Blood c. Organs d. Hair

22. A: Genes are the molecular units that enable parents to pass hereditary traits on to their offspring. The blood, organs, and hair all contain the genes that makeup the offspring, but these are not basic molecular units.

23. Which statement most accurately compares and contrasts the structures of DNA and RNA? a. Both DNA and RNA have 4 nucleotide bases. Three of the bases are the same but the fourth base is thymine in DNA and uracil in RNA. b. Both DNA and RNA have the same 4 nucleotide bases. However, the nucleotides bond differently in the DNA when compared to RNA. c. Both DNA and RNA have 6 nucleotide bases. However, the shape of DNA is a triple helix and the shape of RNA is a double helix. d. Both DNA and RNA have a double helix structure. However, DNA contains 6 nucleotide bases and RNA contains 4 nucleotide bases.

23. A: Both DNA and RNA are made up of 4 nucleotide bases. Both DNA and RNA contain cytosine, guanine, and adenine. However, DNA contains thymine and RNA contains uracil. Choice B is incorrect because DNA and RNA do not have the same 4 nucleotides, and choices C and D are incorrect because neither DNA nor RNA contains 6 nucleotides. Furthermore, DNA has a double helix structure, and RNA has a single helix structure

24. Which of the following characteristics is part of a person's genotype? a. Brown eyes that appear hazel in the sunlight b. CFTR genes that causes cystic fibrosis c. Black hair that grows rapidly d. Being a fast runner

24. B: The genotype describes a person's genetic makeup. The phenotype describes a person's observable characteristics. Among the choices, the CFTR gene refers to genetic makeup while the other choices all describe traits that are observable.

27. Where is the interstitial fluid found? a. In the blood and lymphatic vessels b. In the tissues around cells c. In the cells d. In the ventricles of the brain

27. B: Interstitial fluid is found in the tissues around the cells; intracellular fluid is found within the cells. Fluid in the ventricles of the brain and down into the spinal cord is called cerebrospinal fluid. Cerebrospinal fluid bathes these sensitive tissues in a fluid that helps to protect them. Blood and lymph are the fluids that carry nutrients, oxygen, waste, and lymph material throughout the body

28. Which type of cell secretes antibodies? a. bacterial cell b. viral cell c. lymph cell d. plasma cells

28. D: Plasma cells secrete antibodies. These cells, also known as plasmacytes, are located in lymphoid tissue. Antibodies are only secreted in response to a particular stimulus, usually the detection of an antigen in the body. Antigens include bacteria, viruses, and parasites. Once released, antibodies bind to the antigen and neutralize it. When faced with a new antigen, the body may require some time to develop appropriate antibodies. Once the body has learned about an antigen, however, it does not forget how to produce the correct antibodies.

29. Chemical C is a catalyst in the reaction between chemical A and chemical B. What is the effect of chemical C? a. Chemical C increases the rate of the reaction between A and B. b. Chemical C decreases the rate of the reaction between A and B. c. Chemical C converts A from an acid to a base. d. Chemical C converts A from a base to an acid.

29. A: A catalyst increases the rate of a chemical reaction without becoming part of the net reaction. Therefore, chemical C increases the rate of the reaction between A and B. The catalyst does not change the chemicals within the reaction.

3. Which item below best describes the primary function of the nervous system? a. The nervous system is the center of communication in the body. b. The nervous system is primarily responsible for helping the body breathe. c. The nervous system transports blood throughout the body. d. The nervous system helps the body break down food.

3. A: The nervous system is the body's communication center. The body uses the respiratory system to breathe, and blood is transported by the circulatory system. The digestive system breaks down food for the body.

30. What type of molecules are enzymes? a. Water molecules b. Protein molecules c. Tripolar molecules d. Inorganic molecules

30. B: Enzymes are protein molecules produced by living organisms. Enzymes serve as catalysts for certain biological reactions.

31. Which structure controls the hormones secreted by the pituitary gland? a. hypothalamus b. adrenal gland c. testes d. pancreas

31. A: The hypothalamus controls the hormones secreted by the pituitary gland. This part of the brain maintains the body temperature and helps to control metabolism. The adrenal glands, which lie above the kidneys, secrete steroidal hormones, epinephrine, and norepinephrine. The testes are the male reproductive glands, responsible for the production of sperm and testosterone. The pancreas secretes insulin and a fluid that aids in digestion.

32. Where does gas exchange occur in the human body? a. alveoli b. bronchi c. larynx d. pharynx

32. A: Gas exchange occurs in the alveoli, the minute air sacs on the interior of the lungs. The bronchi are large cartilage-based tubes of air; they extend from the end of the trachea into the lungs, where they branch apart. The larynx, which houses the vocal cords, is positioned between the trachea and the pharynx; it is involved in swallowing, breathing, and speaking. The pharynx extends from the nose to the uppermost portions of the trachea and esophagus. In order to enter these two structures, air and other matter must pass through the pharynx.

33. All of the following belong together except: a. Trachea b. Bronchi c. Esophagus d. Larynx

33. C: The esophagus is the only structure that is not part of the respiratory system, it is part of the digestive system. The larynx houses the voice box; it also acts as a passageway for air to travel into the lungs. The trachea connects the larynx to the lungs. The trachea splits into the right and left bronchi, which divide into smaller passageways called the bronchioles.

34. What lab equipment would most likely be used to measure a liquid solution? a. Flask b. Triple beam balance c. Graduated cylinder d. Test tube

34. C: In order to have accurate measurements, the use of a graduated cylinder would be best. A triple beam balance measures the weight of an object in grams. A flask and a test tube are used to contain a liquid while being heated or stored.

35. An atom has 5 protons, 5 neutrons, and 6 electrons. What is the electric charge of this atom? a. Neutral b. Positive c. Negative d. Undetermined

35. C: The atom is negatively charged. Neutrons have no charge. Protons have positive charge and electrons have negative charge equal in magnitude to the positive charge of the proton. Because the atom has more electrons than protons, the atom has a negative charge.

36. Which system's primary function is to take in oxygen and release carbon dioxide? a. Cardiovascular b. Immune c. Respiratory d. Nervous

36. C: The respiratory system's main role is to take oxygen, distribute it to the body's organs and tissues and excrete carbon dioxide. The major anatomical structures of this system include the nares, larynx, trachea, bronchi, bronchioles, lungs, and diaphragm.

37. Which of the following best describes the structures found underneath each rib in descending order? a. Vein, nerve, artery b. Artery, Vein, Nerve c. Vein, artery, nerve d. Nerve, vein, artery

37. C: The neurovascular structure found under each rib in descending order is the vein, artery, and nerve. When a procedure such as a thoracocentesis or chest tube needs to be performed, the medical professional should aim for directly over the rib in order to avoid damaging to these structures.

39. Which of the following is true regarding the primary function of the spleen? a. It produces bile to emulsify fats b. It filters microorganisms and other foreign substances from the blood c. It helps control blood glucose levels and regulates blood pressure d. It regulates blood clotting factors

39. B: The spleen's job is to filter the blood by removing dead or dying red blood cells as well as microorganisms. In humans it is found in the left upper quadrant of the abdomen lateral to the liver.

4. Which of the following systems is primarily responsible for helping the body breathe? a. Nervous system b. Circulatory system c. Digestive system d. Respiratory system

4. D: The respiratory system uses the lungs, diaphragm, trachea, and bronchi to help the body breathe. The nervous system is the body's center of communication. The circulatory system transports materials through the body, and the digestive system processes food.

40. The process of changing from a liquid to a gas is called ________? a. Freezing b. Condensation c. Vaporization d. Sublimation

40. C: Vaporization is the process of changing from a liquid to a gas. For instance, water vaporizes when boiled to create steam. Freezing is the process of changing from a liquid to a solid. Condensation describes changing from a gas to a liquid, and sublimation is the process of changing from a solid to a gas.

41. A nurse wants to investigate how different environmental factors affect her patients' body temperatures. Which tool would be the most helpful when the nurse conducts her investigation? a. Scale b. Yard stick c. Thermometer d. Blood pressure monitor

41. C: The nurse wants to investigate her patients' body temperatures. A thermometer is the only tool in the list that will help measure the temperature of a person's body.

42. A scientific study has over 2000 data points. Which of the following methods is most likely to help the researcher gain usable information from the data? a. Use statistical analysis to understand trends in the data. b. Look at each individual data point, and try to create a trend. c. Eliminate 90% of the data so that the sample size is more manageable. d. Stare at the data until a pattern pops out.

42. A: The researcher should use statistical analysis to understand trends in the data. Different statistics tools can help manage and examine large data sets. The researcher would probably miss important correlations by looking at the individual data points, and eliminating most of the data would defeat the purpose of conducting the study. Simply staring at the data would not be helpful.

43. Based on this evidence, what is the most likely reason that spoiled food left out in the open often contained fly larvae? a. The spoiled food evolved into fly larvae. b. Since the food was left out in the open, flies would lay eggs in the food. c. Fly larvae were spontaneously generated by the spoiled food. d. People only imagined they saw fly larvae in the spoiled food.

43. B: Based on the evidence, the most likely explanation for fly larvae in the spoiled food is that flies laid their eggs in the food. When the food was left out in the open, the flies had access to it and laid their eggs. However, when the food was in a sealed container, the flies could not lay their eggs in the food. Hence, the spoiled food in the sealed container had no fly larvae.

a. Advances in medical technology enable people to live longer. b. Knowledge about how basic cleanliness can help avoid illness has enabled people to live longer. c. The creation of various vaccines has enabled people to live longer. d. All of the statements above offer reasonable explanations for longer life expectancy.

44. D: Longer life expectancy could be explained by any or all of the alternatives presented. Advances in medical technology, basic cleanliness, and vaccines could all help people live longer in the 21st century

a. The patient looks like he needs this test. b. The doctor feels that the patient needs this test. c. The patient's symptoms and health history suggest that this test will enable the correct diagnosis to help the patient. d. The patient has excellent insurance that will pay for several tests, and the doctor would like to run as many tests as possible.

45. C: A scientific argument should be based on measurable and observable facts such as the patient's current symptoms and health history. Discussing the patient's appearance or the doctor's feelings does not communicate a scientific argument. While insurance may be a factor in most healthcare systems, the status of the patient's insurance does not communicate a scientific argument that justifies the need for the test.

Which of the following is a protein that interferes with virus production? a. Lysozyme b. Prion c. Interferon d. Keratin

46. C: Interferons are members of a larger class of proteins called cytokines. Cytokines are specialized proteins that carry signals between cells. Interferons are proteins that are produced by cells infected by pathogens such as viruses. They signal neighboring cells to produce antiviral proteins which help prevent the spread of infection.

47. Which of the following does not contain blood vessels? a. Hyperdermis b. Hypodermis c. Dermis d. Epidermis

47. D: Humans have three layers of skin called the epidermis, the dermis, and subcutaneous fat. Epidermis is the top layer of the skin, the dermis is the second layer, and subcutaneous makes up the bottom layer. The epidermis does not contain blood vessels.

48. What structure releases hormones that stimulate the gonads during puberty? a. Hypothalamus b. Midbrain c. Basal ganglia d. Hippocampus

48. A: The hypothalamus is a tiny gland at the base of the brain. It helps regulate temperature, sleep, emotions, sexual function and behavior. During puberty it secretes hormones that stimulate the gonads which initiate sexual development.

49. Which of the following structures has the lowest blood pressure? a. Arteries b. Arteriole c. Venule d. Vein

49. D: Of the given structures, veins have the lowest blood pressure. Veins carry oxygen-poor blood from the outlying parts of the body to the heart. An artery carries oxygen-rich blood from the heart to the peripheral parts of the body. An arteriole extends from an artery to a capillary. A venule is a tiny vein that extends from a capillary to a larger vein.

50. Which of the heart chambers is the most muscular? a. Left atrium b. Right atrium c. Left ventricle d. Right ventricle

50. C: Of the four heart chambers, the left ventricle is the most muscular. When it contracts, it pushes blood out to the organs and extremities of the body. The right ventricle pushes blood into the lungs. The atria, on the other hand, receive blood from the outlying parts of the body and transport it into the ventricles. The basic process works as follows: Oxygen-poor blood fills the right atrium and is pumped into the right ventricle, from which it is pumped into the pulmonary artery and on to the lungs. In the lungs, this blood is oxygenated. The blood then reenters the heart at the left atrium, which when full pumps into the left ventricle. When the left ventricle is full, blood is pushed into the aorta and on to the organs and extremities of the body.

51. Which part of the brain interprets sensory information? a. Cerebrum b. Hindbrain c. Cerebellum d. Medulla oblongata

51. A: The cerebrum is the part of the brain that interprets sensory information. It is the largest part of the brain. The cerebrum is divided into two hemispheres, connected by a thin band of tissue called the corpus callosum. The cerebellum is positioned at the back of the head, between the brain stem and the cerebrum. It controls both voluntary and involuntary movements. The medulla oblongata forms the base of the brain. This part of the brain is responsible for blood flow and breathing, among other things.

52. A vaccination is a way of acquiring which type of immunity? a. Passive natural immunity b. Active natural immunity c. Active artificial immunity d. Passive artificial immunity

52. C: A vaccination is a way of acquiring active artificial immunity, where an antigen is deliberately introduced into an individual to stimulate the immune system. Vaccines contain dead or dying pathogens which are not enough to cause an infection, but allow the immune system to "remember" the pathogen and become immune to it

53. Which component of the nervous system is responsible for lowering the heart rate? a. Central nervous system b. Sympathetic nervous system c. Parasympathetic nervous system d. Distal nervous system

53. C: The parasympathetic nervous system is responsible for lowering the heart rate. It slows down the heart rate, dilates the blood vessels, and increases the secretions of the digestive system. The central nervous system is composed of the brain and the spinal cord. The sympathetic nervous system is a part of the autonomic nervous system; its role is to oppose the actions taken by the parasympathetic nervous system. So, the sympathetic nervous system accelerates the heart, contracts the blood vessels, and decreases the secretions of the digestive system.

6. Which item in the following list is NOT one of the major types of bones in the human body? a. Dense bone b. Long bone c. Short bone d. Irregular bone

6. A: The human body has five types of bones: long bones, short bones, irregular bones, flat bones, and sesamoid bones. While bones may be dense, this is not a major category of bones in the body

7. Which of the following bone types is embedded in tendons? a. Long bones b. Sesamoid bones c. Flat bones d. Vertical bones

7. B: Sesamoid bones are embedded in tendons. Choice D, vertical bones, is not a major bone type. Long bones contain a long shaft, and flat bones are thin and curved.

8. You and a lab partner will be completing a scientific experiment measuring the mass of chewed gum after one-minute chewing increments. Which lab equipment will you most likely use? a. Triple beam balance b. Anemometer c. Hot plate d. Microscope

8. A: A triple beam balance would be used to measure the mass (in grams) of the gum in this experiment. An anemometer is used to measure wind speed. A hot plate is used to heat liquids. A microscope is used to magnify microscopic particles or organisms.

9. Which of the following is not a product of respiration? a. carbon dioxide b. water c. glucose d. ATP

9. C: In respiration, food is used to produce energy as glucose and oxygen that react to produce carbon dioxide, water and ATP.