NLN PAX SCIENCE QUESTIONS AND ANSWERS 2026/2027-2027 A Complete And Study material 4pages LEARNEXAMS

autotrophs ✔✔organisms that produce their own food from inorganic substances (plants) heterotrophs ✔✔obtain their food from consuming other plants and animals primary consumers ✔✔omnivores and herbivores secondary consumers ✔✔carnivores tertiary consumers ✔✔carnivores that eat other carnivores decomposers ✔✔bacteria and fungi biotic ✔✔living parts of the ecosystem abiotic ✔✔nonliving influences (temperature, humidity, soil) photosynthesis ✔✔carbon dioxide + water + light energy -> carbohydrates + oxygen angiosperms ✔✔responsible for reproduction structure of a flower ✔✔ segregation ✔✔ codominance ✔✔when traits do not show a pattern of dominance and there are a mixture of two traits how many chromosomes do humans have? ✔✔46 chromosomes what are nucleotides composed of? ✔✔phosphate, deoxyribose, and a nitrogenous base How does RNA differ from DNA? ✔✔it is single stranded, has the sugar ribose in place of deoxyribose, and replaces thymine with uracil what are the common stains used on specimens? ✔✔lugol's solution, methylene blue, and wright's stain independent variable (x- axis) ✔✔changed by the experimenter what enzyme is found in saliva? ✔✔amylase amylase ✔✔breaks down starch into smaller carbohydrate molecules what is gastric juice made up of? ✔✔hydrochloric acid and proteases what is the pH of the stomach? ✔✔2 where does most digestion and absorption of nutrients occur in the body? ✔✔small intestine what enzymes help carbohydrates turn into glucose? ✔✔amylase, sucrase, and maltase what are the 4 chambers of the heart? ✔✔left and right atrium and left and right ventricles what is the first step in blood flow through the heart? ✔✔blood enters the right atrium from the veins called superior vena cava and inferior vena cava what is the purpose of valves in the heart? ✔✔to prevent back flow when the ventricles contract what is the last step in blood flow through the heart? ✔✔the aorta when the heart contracts, the pressure ________ ✔✔increases (systole) when the heart relaxes, the pressure _______ ✔✔lowers (diastole) Is blood considered a connective tissue? ✔✔yes