HESI A2 Biology Practice Exam Questions with Complete Solutions

Which organelle is responsible for protein synthesis? - ANSWER-Ribosome Why is yeast used to make bread rise? - ANSWER-Yeast carries out fermentation, producing ethanol and carbon dioxide How is mitosis different from meiosis? - ANSWER-Meiosis creates sex cells with half the # of chromosomes of the parent cell where as mitosis creates cells that are exact copies of each other, down to the number of chromosomes What can be altered? - ANSWER-DNA What is single stranded? - ANSWER-RNA What contains uracil? - ANSWER-RNA What codes for proteins? - ANSWER-DNA Imagine that two parents both carry the recessive gene for cystic fibrosis. Any homozygous recessive offspring will manifest the disease. What percentage of the offspring is predicted to be carriers but not manifest the disease? - ANSWER-50 percent A cell is in a solution in which the concentration of solutes is higher inside the cell than outside the cell. What would you expect to happen to the cell? - ANSWER-It will swell and probably burst/hypotonic situation What is the purpose of phloem tissue in plant stems? - ANSWER-It conducts food throughout the plant, it is the system of narrow tubes that transports sugars and other nutrients Physical factors such as temperature and pH can alter enzyme activity because they have an effect on the enzyme's - ANSWER-Shape, the shape of an enzyme controls it's fit with its substrate. Which part of a plants reproductive system is of a different gender than others? - ANSWER-Stamen (male reproductive organ) What kind of symbiosis exists between a pneumonia bacterium and a human? - ANSWER-Parasitism, one organism benefits off another